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Medical Policy Stereotactic Radiosurgery and Stereotactic Radiotherapy


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									                                                                            Medical Policy

 Stereotactic Radiosurgery and Stereotactic Radiotherapy

 Type:                                           Policy Specific Section:
 Medical Necessity and                           Surgery
 Investigational / Experimental

 Original Policy Date:                           Effective Date:
 February 26, 1992                               July 7, 2008

Stereotactic describes a procedure during which a target lesion is localized relative to a fixed 3-
dimensional reference system (e.g., rigid head frame, affixed to the patient, fixed bony
landmarks, a system of implanted fiducial markers, or other similar system). This type of
localization procedure allows physicians to perform image-guided procedures with a high degree
of anatomic accuracy and precision.
Stereotactic Radiosurgery (SRS) is a radiation therapy method by which multiple convergent
beams deliver a single focused high dose of radiation to a target lesion. This outpatient procedure
has minimal effects on surrounding tissue and organs and minimizes the complications and
recovery time associated with open brain surgery. Since this single session treatment has such a
dramatic effect on the targeted tissue, targeted changes are considered surgical even though no
incision is made. Since its introduction in recent years, SRS has been primarily used in the
treatment of brain tumors, but the technique can be applied to extracranial lesions as well.
Stereotactic Radiotherapy (SRT) is a technique of radiation therapy where an optimum radiation
treatment dose for a tumor is subdivided into smaller, cumulative doses. These hypofractionated
treatments are delivered with stereotactic guidance over a period of several days to several
weeks. Because the total dose is given in installments, radiation side effects are usually lessened
since normal cells have time to heal between treatments.
Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

In either case, a radiation oncologist, a neurosurgeon and a radiation physicist work together to
create an individualized, computerized treatment plan for each patient. Guidance is provided by a
variety of imaging techniques, including angiography, computerized tomography (CT), and
magnetic resonance imaging (MRI).
Five main methods of this technology exist: gamma-ray radiosurgery (GammaKnifelinear-
accelerator radiosurgery (LINAC) including Cyberknifeproton-beam radiosurgery, helium-ion
radiosurgery, and neutron-beam radiosurgery. The latter 3 energy sources are collectively
referred to as charged particles. (Further detailed information in Background section below)
Please see the following Blue Shield of California (BSC) related Medical Policies for additional
     •    Charged-Particle (Proton or Helium Ion) Radiation Therapy (non-stereotactic
     •     Intensity Modulated Radiation Therapy (IMRT)

Stereotactic radiosurgery using a Gamma Knife®, LINAC (linear accelerator) including
Cyberknife®, or proton beam unit may be considered medically necessary and effective when
used in the treatment of small (< 4 cm in diameter or <12 ml) and no more than 3 lesions for any
of the following indications:
     •    Arteriovenous malformations (AVM) (inoperable AVM's of the brain which are less than
          or equal to 5 cm in greatest dimension);
     •    Benign brain tumors such as meningiomas and acoustic neuromas (also known as
          vestibular schwannomas);
     •    Pituitary adenomas (Cushing's disease or acromegaly);
     •    Non-resectable, residual, or recurrent meningiomas;
     •    Solitary or multiple brain metastases (initial or recurrent treatment) in patients having
          good performance status and no active systemic disease (defined as extracranial disease
          that is stable or in remission);
     •    Primary malignancies of the Central Nervous System (CNS), including but not limited to
          high grade malignant gliomas (i.e., anaplastic gliomas and glioblastoma multiforme)
          (initial treatment or treatment of recurrence);
     •    Trigeminal neuralgia refractory to conservative medical treatment;
     •    Early stage (stage I) primary non-small cell lung cancer (NSCLC) that is inoperable;
     •    Hepatocellular carcinoma (HCC) that is localized and inoperable;
     •    Isolated liver metastases in patients who are poor candidates for surgery;

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

     •    Localized prostate cancer of low to intermediate risk (Gleason Score less than or equal to
     •    Spinal and paraspinal tumors;
     •    Spinal and paraspinal tumor metastases;
All other uses of stereotactic radiosurgery are considered investigational and include, but are not
limited to:
     •    Treatment of functional disorders other than trigeminal neuralgia (i.e., Parkinson's
     •    Epilepsy;
     •    Chronic pain
Note: Charged-particle radiation can also be used without stereotactic guidance. In this setting,
the use of charged particles is referred to as proton, helium or neutron radiation therapy.
Applications of this therapy are discussed in a separate policy Charged-Particle (Proton or
Helium Ion) Radiation Therapy (non-stereotactic applications).

SRS is a proposed alternative to conventional surgery. Radiosurgery has potential advantages
over open surgery in that it is not invasive and can more easily address inaccessible or multiple
lesions. In addition, the border zone between the lesion and normal tissue may receive a radiation
dose sufficient to decrease the risk of local recurrence. The two major disadvantages of
radiosurgery are that it generally is applicable only to lesions less than about 2.5-3.0 cm in
diameter and that it results in slow tumor shrinkage over weeks or months rather than relieving
mass effect immediately. The primary risk of radiosurgery is radiation necrosis, which may
occur 6-24 months after treatment and is related to the dose delivered and the volume treated.

The GammaKnife and linear accelerator (LINAC) systems are similar in concept and in efficacy;
both use multiple photon radiation arcs that intersect at a stereotactically determined target, thus
permitting higher doses of radiation delivery with sparing of surrounding normal tissues. The
differences between the two relate to how the energy is produced (i.e., through decaying cobalt
or from x-rays) and the number of energy sources used (i.e., multiple energy sources in the
gamma knife versus 1 in the linear accelerator system). In a multi-center clinical trial that
examined the two systems in the treatment of brain metastasis, no differences in efficacy or
toxicity were observed in patients treated with GammaKnife and LINAC. Charged-particle
beams are fundamentally different in that they take advantage of the Bragg peak phenomenon
(i.e., the deposition of energy at a specific depth with minimal scatter). Typically, 3 to 5 fixed
beams are used, similar to the beam arrangement in conventional radiotherapy.
The differences in the various stereotactic radiation systems are summarized in the following

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

Device                                      Energy Source                      Energy Characteristics
Gamma Knife                                 201 separate cobalt-60 sources Gamma rays, consisting of
                                            arranged in a steel shell;     two photons with an average
                                            beams intersect on target      energy of 1.25 MeV
Cyberknife                                  Device consists of a               1) An advanced, lightweight
                                            lightweight linear accelerator     linear accelerator (LINAC)
                                            (LINAC) mounted on a six-          (this device is used to produce
                                            axis robotic manipulator that      a high energy (6MeV) "killing
                                            permits a wide range of beam       beam" of radiation), 2) A
                                            orientations combined with         robot which can point the
                                            real- time image guidance and      linear accelerator from a wide
                                            guided delivery which              variety of angles, and 3)
                                            eliminates the need for a head     Several x-ray cameras
                                            frame or other skeletal fixation   (imaging devices) that are
                                                                               combined with powerful
                                                                               software to track patient
Linear accelerator adapted for              Single beam of x-rays, rotated     X-rays, consisting of photons
stereotactic use                            to produce multiple                with an average energy of 2
                                            intersecting beams                 MeV
Charged particles                           3 to 5 fixed beams of protons,     Charged particles have
                                            neutrons, or helium ions           minimal scatter as they pass
                                                                               through tissue, depositing
                                                                               ionizing energy at a precise
                                                                               depth (Bragg peak)

The radiosurgical procedure is preceded by a process of localizing the target, which can be
performed with 1 or more of the following techniques: cerebral angiography, computed
tomography, and magnetic resonance imaging. SRS is typically performed in 1 session, usually
requiring no more than an overnight stay. Stereotactic radiotherapy refers to stereotactically
guided radiation therapy applied over several days. This fractionated form of radiation therapy is
made possible by the recent availability of noninvasive repositioning devices that can be used in
lieu of a head frame. Stereotactic radiotherapy is based on the basic radiobiologic principle that
fractionation decreases the short and long-term side effects of radiation therapy. In some settings,
this permits higher total dosage to be given.
Image-guided radiosurgery or radiotherapy is a relatively new development collectively
describing techniques that can vary radiation therapy delivery by patient. One example is the
Cyberknife device, consisting of a lightweight linear accelerator (LINAC) mounted on a six-axis
robotic manipulator that permits a wide range of beam orientations. In addition, the Cyberknife
uses real-time image guidance, which eliminates the need for a head frame or other skeletal
fixation. The Cyberknife system incorporates two diagonal x-ray cameras positioned

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

orthogonally to acquire real-time images of the patient s internal anatomy during movement. The
images identify internal anatomic landmarks, including implanted markers (referred to as
fiducials), which are then automatically compared with a prior treatment planning CT scan. The
precise tumor position is then communicated to the robotic arms that align the radiation beam
with the intended target. These planning techniques are collectively referred to as image-guided
radiation therapy. The Cyberknife device is essentially a technique for delivering intensity
modulated radiation therapy (IMRT) (i.e., the use of treatment beams of varying different
intensities administered from different directions, combined with image-guided delivery), albeit
with inverse algorithm and limited by coned beams. Other techniques for delivering IMRT
include the use of multi-leaf collimators, tomotherapy, and the step and shoot technique.

Stereotactic Radiotherapy
Stereotactic radiotherapy (SRT), also known as hypofractionated or staged stereotactic
radiosurgery (SRS), is a process in which the total dose of stereotactic radiation is divided into
several smaller doses, with each dose delivered on a separate day. Normal tissues are spared
because the treatment is given over sequential days. In stereotactic radiotherapy (SRT) radiation
is delivered at different times, at lower intensities to the target lesions. In contrast, stereotactic
radiosurgery (SRS) is delivered in high doses all at once in a single session to the target lesions.
The major advantage of fractionation is that higher doses of radiation can be delivered to the
tumor because the surrounding normal tissues are able to tolerate these smaller fractionated
Challenges to an Evidence-Based Approach to Rapidly Evolving Technologies in Radiation
This policy groups together several different techniques for delivering stereotactic radiosurgery,
including the Gamma Knife, LINAC devices (including Cyberknife), and proton beam
radiotherapy. However, from an evidence-based approach, it is difficult to compare these
different modalities to determine if one is superior to another for a particular indication. In a
multi-center phase III RTOG (Radiation Therapy Oncology Group) clinical trial in 2004,
Gamma Knife and LINAC were found to be of similar efficacy and toxicity in the treatment of
brain mestastases. A literature search in 2008 failed to identify any controlled trials directly
comparing all of the SRS modalities of treatment in homogeneous groups of patients. In addition,
the field of radiation oncology is rapidly evolving with current intense interest in emerging
image-guided technology. A limited number of stereotactic radiosurgery options may be
available in individual markets, and thus the choice among devices may be dictated primarily by
Size of Lesion
In terms of stereotactic radiosurgery, the superiority of one energy source over another depends
primarily on the dose distribution capabilities, which in turn depend on the target's volume,
location, and shape. For small lesions (i.e., <5 cm3), the dose distributions produced by the
Gamma Knife are essentially identical to those achievable with LINAC units. When the target
lesion is nonspherical or of intermediate size (e.g., between 5 and 25 cm3 ), LINAC units may

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

have an advantage over Gamma Knife units, due to their ability to treat larger lesions without
requiring multiple isocenters (which makes treatment planning difficult), and the ability to shape
the dose using collimated fields. However, when targeting large volumes (i.e., >25 cm3 ),
charged particle units that use a small fixed number of beams have the best ability to shape dose
distributions and thus offer some advantages over both LINAC and Gamma Knife units.
Dose Fractionation
Standard radiologic principles suggest that fractionating radiation therapy (i.e., delivery in
multiple sessions) will reduce both early and late toxicities to surrounding normal tissues.
Radiosurgery (one treatment) or hypofractionation (limited number of treatments) may be
considered when patient movement limits the use of conventional radiation therapy, or may be
offered as a convenience to patients, particularly those that require rapid pain relief. These two
clinical indications are also associated with different outcomes that must be considered as part of
an evidence-based analysis. A more basic scientific issue is an underlying understanding of the
radiosensitivity of surrounding normal tissues.
Dose Escalation
New forms of radiation therapy, for example, the Cyberknife, other techniques of delivering
IMRT, and proton beam therapy have been proposed as ways to provide dose escalation. In this
setting, clinical questions include whether or not dose escalation provides improved tumor
control, which depends on the dose response rate of individual tumor types, and whether an
increased dose is associated with increased toxicity to surrounding tissues.
Decreased Toxicity
A variety of novel treatment planning and delivery approaches are designed to reduce toxicity.
The ability of the Cyberknife to accommodate patient movement is a unique feature and a variety
of applications have been suggested, including treatment of lung, prostate, and pancreas cancer.
In these settings, respiratory motion can limit the ability to deliver IMRT, and thus the
Cyberknife may be considered an alternative to multileaf collimators, tomotherapy, or the step
and shoot technique. Evidence of reduced toxicity would require directly comparative studies.
Many of the potential benefits of the Cyberknife and other treatment delivery systems have been
based on modeling studies, or studies with phantoms, and clinical experiences have been much
more limited.
In summary, the lack of comparative studies of different techniques of radiation planning and
delivery in homogeneous groups of patients limits any scientific analysis regarding the relative
safety and efficacy of different systems for different clinical situations (i.e., reduction of
fractionation, dose escalation, reduced toxicity, or a combination of all three). Therefore, the
scientific evidence is inadequate to permit scientific conclusions regarding the superiority of one
device over another. The following discussion focuses on different general applications of
stereotactic radiosurgery and radiotherapy.

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

The peer reviewed medical literature supports stereotactic radiosurgery, using either gamma ray
(Gamma Knife) or x-ray (LINAC, including Cyberknife) as an effective method of treatment for
arteriovenous malformations, acoustic neuromas, pituitary adenomas, some types of
meningiomas, brain metastases, high grade gliomas, and trigeminal neuralgia. Multiple well-
controlled randomized clinical trials continue to show evidence supporting the conclusion that
this procedure has demonstrated an advantage over traditional radiation treatments allowing high
dose delivery and minimal radiation exposure to surrounding normal tissue. More recently, SRS
has been investigated as a treatment of functional disorders, including trigeminal neuralgia,
epileptic seizures, and chronic pain.
Intracranial metastases have also been considered ideal targets for radiosurgery due to their small
spherical size, non-infiltrative borders, and location in non-eloquent areas of the brain. Brain
metastases are a frequent occurrence, seen in 25% to 30% of all patients with cancer, particularly
in those with lung, breast, colon cancer or melanoma. The treatment of primary brain tumors
such as gliomas is more challenging, due to their generally larger size and infiltrative borders.
Acoustic neuromas are benign tumors originating on the eighth cranial nerves, and they can be
seen in association with neurofibromatosis. Although these tumors are benign, they are
associated with significant morbidity and even death if their growth compresses vital structures.
Treatment involves complete surgical excision using microsurgical techniques, but radiosurgery
has also been investigated, either as a primary treatment or as a treatment of recurrence after
incomplete surgical resection. In fact, acoustic neuromas were one of the first indications for
Gamma Knife radiosurgery, dating back to 1969.
Stereotactic Radiotherapy (SRT) treatment of acoustic neuromas, where the most significant
desired effect is functional preservation of the facial and auditory nerve, has also been studied.
In a single institution study, Meijer and colleagues reported on the outcomes of single fraction
versus fractionated LINAC-based stereotactic radiosurgery in 129 patients with acoustic
neuromas. With an average follow-up of 33 months, there was no difference in outcome in terms
of local tumor control, facial nerve and hearing preservation. Chung and colleagues reported on
the results of a single institution case series of 72 patients with acoustic neuromas, 45 who
received single fraction therapy and 27 who received fractionated therapy. Patients receiving
single fraction treatment were functionally deaf, while those receiving fractionated therapy had
useful hearing in the affected ear. After a median follow-up of 26 months, there was no tumor
recurrence in either group. Chang reported that 74% of 61 patients with acoustic neuromas
treated with Cyberknife using staged treatment had serviceable hearing maintained at least 36
months of follow-up. Three other single-institution case series also reported on 87 patients with
metastatic disease, 143 patients with astrocytomas, and 36 patients with cerebral AVMs,
respectively, who were treated with fractionated stereotactic radiotherapy. While all reported
promising outcomes, the lack of a control group receiving stereotactic radiosurgery severely
limits interpretation.
Pituitary adenomas are benign tumors with symptoms that are related to hormone production
(i.e., functioning adenomas) or to neurologic symptoms due to their impingement on surrounding
neural structures. Treatment options for pituitary adenomas include surgical excision,

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

conventional radiation therapy, or SRS. Surgical excision is typically offered to patients with
functioning adenomas, since complete removal of the adenoma is required to control the
autonomous hormone production and the effects of radiation therapy may be delayed or
incomplete. In patients with nonfunctioning adenomas, treatment goals are to control growth;
complete removal of the adenoma is not necessary. Conventional radiation therapy has been used
in this setting with an approximate 90% success rate with rare complications.
Arteriovenous malformations consist of a tangled network of vessels in which blood passes from
arteries to veins without intervening capillaries. They range in size from small, barely detectable
lesions to huge lesions that can occupy an entire hemisphere. SRS incites an inflammatory
response in the vessels, which results in ongoing fibrosis with eventual complete obliteration of
the lesion over a course of months to years. This latency period is variable, depending on the size
of the AVM and the dose distribution of the radiosurgery. During this latency period, there is an
ongoing but declining risk of hemorrhage whereas surgical excision provides an immediate risk
of hemorrhage. Total surgical extirpation of the lesion, if possible, is the desired form of therapy
to avoid future hemorrhage. However, a small subset of AVMs because of their size or location
cannot be excised without serious neurological sequelae. SRS is an important alternative in these
Trigeminal neuralgia is a disorder of the fifth cranial (i.e., trigeminal) nerve that causes episodes
of intense, stabbing pain in the face. Although trigeminal neuralgia is initially treated medically,
in a substantial number of cases, drug treatment is either ineffective or the adverse effects
become intolerable. Neurosurgical options include microvascular decompression, balloon
compression, and rhizotomy. SRS has been investigated as an alternative to these neurosurgical
treatments. Patients with trigeminal neuralgia are frequently elderly and not candidates for
conventional surgery. Studies have shown that patients who have undergone SRS treatment for
trigeminal neuralgia experience 80-85% improvement of pain. It must be noted that as many as
40% of patients experience recurrence of pain within five years.
Intracranial stereotactic radiosurgery has been studied for a variety of other indications including
seizure disorders (epilepsy), chronic pain, and functional or movement disorders. Seizure
disorders are initially treated medically, and due to its potential morbidity, surgical treatment is
only considered in those rare instances when the seizures have proven refractory to all attempts
at aggressive medical management, when the seizures are so frequent and severe as to
significantly diminish quality of life, and when the seizure focus can be localized to a focal
lesion in a region of the brain that is amenable to resection. SRS has been investigated as an
alternative to neurosurgical resection.
The 1998 TEC Assessment cited 2 studies of 11 and 9 patients, in which radiosurgery was used
to treat epilepsy. The subsequent literature search revealed 3 small studies on the use of
radiosurgery for medically refractory epilepsy. Regis et al selected 25 patients with mesial
temporal lobe epilepsy, of which 16 provided minimum 2-year follow-up. Seizure-free status
was achieved in 13 patients, 2 patients were improved, and 3 patients had radiosurgery-related
visual field defects. Schrottner et al included 26 patients with tumoral epilepsy, associated
mainly with low-grade astrocytomas. Mean follow-up among 24 available patients was 2.25
years. Tumor location varied across patients. Seizures were simple partial in 6 (3 with
generalization) and complex partial in 18 (5 with generalization, 1 gelastic). Seizures were

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

eliminated or nearly so in 13 patients. Little improvement was observed in 4 patients and none in
7. Whang and Kwon performed radiosurgery in 31 patients with epilepsy associated with non-
progressive lesions. A minimum of 1-year follow-up was available in 23 patients, of whom 12
were seizure-free, 3 had anti-seizure medications discontinued, 2 had seizures reduced in
frequency, and 9 experienced no change. While the Regis series selected a fairly homogeneous
clinical sample, the other 2 studies were heterogeneous. No confirmatory evidence is available
on mesial temporal lobe epilepsy. The available evidence from patients with epileptic lesions of
various sizes and locations is insufficient to show what factors are associated with favorable
outcome. There is inadequate reporting of complications associated with radiosurgery. The
studies published to date are preliminary in nature. The 1998 TEC Assessment observed that
evidence was insufficient to permit conclusions about the effects of radiosurgery on epilepsy.
Conclusions about the health outcome effects of radiosurgery await additional studies.
A variety of surgical alternatives for chronic pain that is refractory to medical and psychological
treatments are available. Neurodestructive procedures include cordotomy, myelotomy, and
stereotactic radiofrequency thalamotomy. SRS targeting the thalamus has been considered an
alternative to these neurodestructive procedures. The TEC Assessment from 1998 identified 2
papers, with 2 and 47 patients, who underwent radiosurgical thalamotomy for chronic pain. No
new studies were found in the search of recent literature. Thus, the conclusions of the 1998 TEC
Assessment have not changed.
In these cases, there is a lack of evidence comparing the safety and effectiveness and health
outcomes of SRS to standard therapies. Patient selection criteria, optimum radiation dose, and
maximum treatment volume remain issues that require further study.
Treatment of Extracranial Sites
Although SRS and SRT have mostly been used in the treatment of brain lesions, there is an
emerging body of evidence in extracranial SRS and stereotactic body radiation therapy (SBRT).
Early and incomplete evidence at this time suggests that extranial SRS and SBRT may be
efficacious and medically necessary in treating stage I primary non small cell lung carcer
(NSCLC); head and neck cancers of squamous cell origin; hepatocellular carcinoma (HCC) and
isolated liver metastases; spinal and paraspinal tumors.
Non Small Cell Lung Cancers
SBRT for NSCLC has been relatively well studied. From 2005-2007, no fewer than seven trials
reported on overall positive outcomes of hypofractionated SBRT for early stage (Stage I)
NSCLC. Although surgical resection is the preferred approach for early stage NSCLC, these
studies demonstrated good local control could be achieved with SBRT, for surgically respectable
and unsectable tumors. In the largest case study by Onishi et al, 300 patients with stage I
NSCLC in a multi-institution Japanese trial received varying radiation doses of 18 to 75 Gy
delivered in 1 to 22 fractions. Favorable five-year survival rate of 74% was achieved in those
subjects that received a biologic equivalent dose (BED) of >100 Gy. Timmerman concluded that
prospective trials using SBRT in North America have been able to identify potent tolerant dose
levels and confirm their efficacy, but also noted that sometimes debilitating toxicity has been
observed for patients with tumors near the central airways. Hof reported on outcomes (median
follow-up 15 months) for 42 patients with stages I and II lung cancer who were not suitable for

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

surgery and who were treated with stereotactic radiotherapy. In this series, at 12 months overall
survival was 75% and disease-free survival was 70%. Better local control was noted with higher
doses of radiation. Early preliminary results were also noted for this treatment approach with
liver, renal, and prostate cancer.
Zimmerman et al. (2006) performed SRS on 68 inoperable patients with a median age of 76
years who had non-small cell lung cancer stage 1. Exclusions included patients who were
previously administered chemo- or thoracic radiotherapy. The results indicated a local tumor
control rate of 96%, 88%, and 88% after one, two, and three year follow up. Cancer specific
survival was 96%, 82%, and 73% at one, two, and three years. Eleven of the patients died from
comorbidities, making a 53% overall three year survival rate. The authors concluded that their
SRS protocol was safe for elderly patients with Stage 1 NSCLC and significantly reduced lung
capacity. The protocol leads to high local control rates. The authors further advised that it should
be offered to patients who were not amenable for a curative tumor resection.
Hodge et al. (2006) reported on the feasibility of SBRT for medically inoperable T1/2 N0 M0
non-small cell lung cancer in nine patients. The authors advised that delivery of SBRT in patients
with early stage medically inoperable non-small cell lung cancer is feasible and well tolerated.
Further studies would be warranted for evaluation of the efficacy of their treatment protocol.
In 2006 Timmerman et al. conducted a prospective phase II trial. SRS was performed on 70
patients with clinically staged T1 or T2 (< or =7 cm), N0, M0, biopsy-confirmed NSCLC who
had comorbities that prohibited lobectomy. Sixty percent (60%) of patients had major response
rates at 3 months. At two years, local control was at 95%. Median overall survival was 32.6
months and two year overall survival was 54.7%. Fourteen (14) patients developed grade 3-5
toxicity. It was noted that patients who had peripheral lung tumors had a lower rate of severe
toxicity as compared to patients with central lung tumors. The authors concluded that local
control was high with their regimen for inoperable patients with NSCLC and local recurrence
and toxicity occurred late after treatment.
Hepatocellular Carcinoma (HCC) and Liver Metastases
In 2001, Herfarth et al published one of the first phaseI/II trial findings of SRS treatment for
localized primary HCC as well as metastatic liver lesions. SRS single-dose was performed on 37
patients with 60 liver tumors (3 primary HCC and 57 liver metastases). 98% of tumors were
locally controlled at 6-week follow-up, with 81% control at 18-months.
In 2004, Lin et al studied SBRT in HCC patients with unresectable tumors and portal vein tumor
thrombosis (PVTT) who were contraindicated for Transarterial Chemoembolization (TACE)
therapy, and reported that SRT could recanalize the PVTT in unresectable HCC patients, and
achieved improved 1- and 2-year survival in responders.
In 2006, Choi et al reported on SBRT for primary HCC in a small case study of 20 patients. Five
or 10 fractions of SBRT were delivered over 2 weeks. Overall response rates were favorable,
with 80% showing complete or partial response, and median survival and median disease-free
survival of 20 and 19 months respectively.
In 2008, Tse et al reported findings of phase I trial of SBRT for unresectable primary
hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (IHC), with 6-fraction

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
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Effective Date: 7/07/2008

SBRT. Results were overall favorable, given the aggressive and unresectable nature of the
tumors, with median survival of 11.7 and 15 months for HCC and IHC respectively.
In 2005, Schefter et al published phase I trial findings for maximum tolerated dose of SBRT for
liver metastases, and concluded that biologically potent dose of 60Gy was well tolerated in
patients with limited metastatic liver lesions.
In 2006, Kavanagh et al. reported an interim analysis of prospective Phase I/II study of SBRT for
liver metastases. Thirty-six patients with liver metastases with a maximum tumor diameter of <
cm and less than or equal to 3 discrete lesions have been enrolled. Their most common primary
sites are the lung, colorectal and breast cancer. Patients received 60 Gy in 3 fractions of SBRT
over 3-14 days. Interim results demonstrate local control at 18 months of 93% (21 patients with a
median 19 months post SBRT follow up, with 28 lesions). This interim analysis of these results
indicated that a high rate of durable in-field tumor control can be safely achieved with SBRT to
1-3 liver lesions as administered in this protocol. The results support the continuation of the trial
into the second phase as more patients are added.
In 2007, Katz et al. conducted a retrospective review of 69 patients (174 with metastatic liver
lesions) treated with hypofractionated SBRT for the treatment of liver metastases. Sixty patients
were evaluated by an abdominal computer tomography scan at a minimum of three months after
SBRT was completed. The overall in-field local control rate of the irradiated lesions was 76%
and 57% at 10 and 20 months, respectively. The median overall survival time was 14.5 months.
The progression free survival rate was 46% and 24% at six and 12 months. None of the patients
developed Grade 3 or higher toxicity. The authors advised that hypofractionated SBRT provides
excellent control with minimal side effects in selected patients with limited hepatic metastases.
Prostate Cancer
Head to head comparison studies of radiation therapy versus surgery for prostate cancer is
generally lacking. Outcome interpretation is difficult and often biased, due to lead-time and PSA
end-point (biochemical progression-free survival) bias. Currently, external beam radiation
therapy (EBRT), including IMRT and IGRT, and brachytherapy (interstitial radioactive seeds)
are the two modalities that are considered effective.
Most studies done regarding SRS and prostate cancer are feasibility studies. King et al. (2003)
reported that there is a clear dose response for localized prostate cancer radiotherapy and a
probable radiobiological rationale for hypo-fractionation. This study discussed stereotactic
radiosurgery for localized prostate cancer and examined the rationale and technical feasibility of
using the Cyberknife and hypo-fractionated regimens. The authors argued that this combination
should maximize tumor control and increase therapeutic ratio. They also suggested that SRS with
Cyberknife could provide superior target coverage and dose volume histograms for sparing of
the rectum and bladder as compared to IMRT.
There is discussion in the literature as to whether prostate cancer treatment using the Cyberknife
robotic system should be considered as a new treatment and then investigated through classical
clinical research procedure rather than technical improvement of an already validated treatment.
Hannoun-Levi et al. (2007) presented a comparison of the CyberKnife and other validated
treatments for prostate cancer (radical prostatectomy, 3 D conformal radiation therapy and low

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

and high dose rate brachytherapy). The authors summarized that CyberKinfe treatment should be
considered as a technical improvement of an already validated treatment in order to deliver a
prostate boost after pelvic or peri-prostatic area irradiation.
Spinal Lesions
The site most studied involves spinal and paraspinal lesions. The spine is uniquely suitable for
SRS because of its sensitivity to radiation toxicity, and because the side effect of radiation
myelopathy is worrisome. In one of the largest case series, Gerszten and colleagues in 2004
reported on the outcomes of 115 consecutive patients with 125 spinal tumors of varying
etiologies (i.e., benign, metastatic, single, or multiple lesions, in a variety of locations [cervical,
thoracic, lumbar, and sacral] that were treated with the Cyberknife in a single session. Axial and
radicular pain improved in 74 of the 79 symptomatic patients. There was no acute radiation
toxicity or new neurologic deficits in the follow-up period (9-30 months; median 18 months).
Conventional external beam radiation therapy typically is delivered over a course of 10 to 20
fractions. In contrast, in this study only 1 Cyberknife treatment session was used. In a 2005
study, Degen and colleagues reported on the outcomes of 51 patients with 72 spinal lesions who
were treated with the Cyberknife. Patients underwent a median of 3 treatments. Pain was
improved, as measured by declining mean visual analogue scale (VAS) score, and quality of life
was maintained during the 1-year study period.
Gerszten in 2007 published results on a series of 500 cases from a single institution using the
Cyberknife system. In this series, the maximum intratumoral dose ranged from 12.5 to 25 Gy
with a mean of 20 Gy. Long-term pain improvement occurred in 290 of 336 cases (86%). Long-
term radiographic tumor control was demonstrated in 90% of lesions treated with radiosurgery as
a primary treatment modality. Twenty-seven of 32 cases (84%) with a progressive neurologic
deficit before treatment experienced at least some clinical improvement. While the results show
pain improvement, the extent of pain relief and impact of quality of life is not reported. As noted
above in the rationale, comparative studies are needed along with more details about relevant
outcomes. Chang reported on phase I/II results of SBRT in 74 spinal lesions in 63 patients with
cancer. The actuarial 1-year tumor progression-free incidence was 84%. Pattern-of-failure
analysis showed 2 primary mechanisms of failure: recurrence in the bone adjacent to the site of
previous treatment; and recurrence in the epidural space adjacent to the spinal cord. The authors
concluded that analysis of the data obtained in their study supports the safety and effectiveness
of SBRT in cases of metastatic spinal tumors. They add that they consider it prudent to routinely
treat the pedicles and posterior elements using a wide bone margin posterior to the diseased
vertebrae because of the possible direct extension into these structures, and for patients without a
history of radiotherapy, more liberal spinal cord dose constraints than those used in the study.

Benefit Application
Benefit determinations should be based in all cases on the applicable contract language. To the
extent there are any conflicts between these guidelines and the contract language, the contract
language will control. Please refer to the member’s contract benefits in effect at the time of
service to determine coverage or non-coverage of these services as it applies to an individual

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

Some state or federal mandates (e.g., Federal Employee Program (FEP)) prohibit Plans from
denying Food & Drug Administration (FDA) - approved technologies as investigational. In these
instances, plans may have to consider the coverage eligibility of FDA-approved technologies on
the basis of medical necessity alone.

This Policy relates only to the services or supplies described herein. Benefits may vary
according to benefit design; therefore, contract language should be reviewed before applying the
terms of the Policy. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not
constitute or imply member coverage or provider reimbursement Policy

 Type                Code                     Description

 CPT                 20660                    Application of cranial tongs, caliper, or stereotactic frame,
                                              including removal (separate procedure)
                     61793                    Stereotactic radiosurgery (particle beam, gamma ray or linear
                                              accelerator), one or more sessions
                     61795                    Stereotactic computer-assisted volumetric (navigational)
                                              procedure, intracranial, extracranial, or spinal (List
                                              separately in addition to code for primary procedure)
                     77299                    Unlisted procedure, therapeutic radiology clinical treatment
                     77371                    Radiation treatment delivery, stereotactic radiosurgery
                                              (SRS), complete course of treatment of cranial lesion(s)
                                              consisting of 1 session; multi-source Cobalt 60 based
                     77372                    Radiation treatment delivery, stereotactic radiosurgery
                                              (SRS), complete course of treatment of cranial lesion(s)
                                              consisting of 1 session; linear accelerator based
                     77373                    Stereotactic body radiation therapy, treatment delivery, per
                                              fraction to 1 or more lesions, including image guidance,
                                              entire course not to exceed 5 fractions
                     77399                    Unlisted procedure, medical radiation physics, dosimetry and
                                              treatment devices, and special services
                     77432                    Stereotactic radiation treatment management of cranial
                                              lesion(s) (complete course of treatment consisting of one
                     77435                    Stereotactic body radiation therapy, treatment management,
                                              per treatment course, to one or more lesions, including image
                                              guidance, entire course not to exceed 5 fractions

Medical Policy                                                                                  13 of 18
Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

 Type                Code                     Description

                     77520                    Proton treatment delivery; simple, without compensation
                     77522                    Proton treatment delivery; simple, with compensation
                     77523                    Proton treatment delivery; intermediate
                     77525                    Proton treatment delivery; complex
 HCPCS               G0173                    Linear accelerator based stereotactic radiosurgery, complete
                                              course of therapy in one session
                     G0251                    Linear accelerator based stereotactic radiosurgery, delivery
                                              including collimator changes and custom plugging,
                                              fractionated treatment, all lesions, per session, maximum
                                              five sessions per course of treatment
                     G0339                    Image guided robotic linear accelerator-based stereotactic
                                              radiosurgery, complete course of therapy in one session, or
                                              first session of fractionated treatment
                     G0340                    Image guided robotic linear accelerator-based stereotactic
                                              radiosurgery, delivery including collimator changes and
                                              custom plugging, fractionated treatment, all lesions, per
                                              session, second through fifth sessions, maximum five
                                              sessions per course of treatment
 ICD-9               Multiple
 ICD-9               92.25                    Teleradiotherapy using electrons
                     92.26                    Teleradiotherapy or other particulate radiation
                     92.29                    Other radio-therapeutic procedure
                     92.30                    Stereotactic Radiosurgery, not otherwise specified
                     92.31                    Single source photon radiosurgery
                     92.32                    Multi source photon radiosurgery
                     92.39                    Stereotactic Radiosurgery, not elsewhere classified
 Place of            Hospital Inpatient
 Service             Hospital Outpatient/Surgicenter

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

Prior Authorization Requirements
Prior-Authorization is required. Clinical Evidence to support medical necessity must be
provided and used for determination (see below). Prior authorization requests must be submitted
with the appropriate procedure codes.
To obtain authorization, contact the Prior Authorization Department at 1-800-343-1691 or visit
the Provider Portal www.blueshieldca.com/provider.

  Documentation Required for Clinical Review

  Include all of the following documents applicable to the patient's diagnosis:
  History & physical and/or Consultation notes including:
       •    Diagnosis, lesion descriptions including size, number, and location, and history of
            treatments (if applicable)
       •    Medical Oncologists progress report indicating systemic disease status within the past
            2 months
       •    Documentation of functional and performance status over the past 3 months
       •    Tumor Node Marker (TNM) classification (except if tumor does not have a TMN
            classification (i.e., brain tumors))
       •    Gleason score for prostate cancer
       •    Daily Treatment Records (for retro review claims)
       •    Any radiological reports in the past 2 months must include brain, bones & abdominal
            CTs or MRIs
       •    With arteriovenous malformations (AVMS) neuromas, gliomas, indicate size and
            therapy tried for patient's condition
       •    Associated radiological procedure codes to be billed

1.     Aoyama H, Shirato H, Onimaru R et al. Hypofractionated stereotactic radiotherapy alone
       without whole brain irradiation for patients with solitary and oligo brain metastasis using
       noninvasive fixation of the skull. Int J Radiat Oncol Biol Phys 2003; 56(3):793-800.
2.     Aoyama H, Shirato H, Tago M et al. Stereotactic radiosurgery plus whole-brain radiation
       therapy vs stereotactic radiosurgery alone for treatment of brain metastases: a randomized
       controlled trial. JAMA 2006; 295(21):2483-91.

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Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

3.     Chang EL, Shiu AS, Mendel E et al. Phase I/II study of stereotactic body radiotherapy for
       spinal metastasis and its pattern of failure. J Neurosurg Spine 2007; 7(2):151-60.
4.     Chang SD, Adler JR. Robotic and radiosurgery--the CyberKnife. Stereotact Funct
       Radiosurg 2001; 76(3-4):204-8.
5.     Chang SD, Gibbs IC, Sakamoto GT et al. Staged stereotactic irradiation for acoustic
       neuroma. Neurosurgery 2005; 56(6):1254-61.
6.     Chung HT, Ma R, Toyota B et al. Audiologic and treatment outcomes after linear
       accelerator-based stereotactic irradiation for acoustic neuroma. Int J Radiat Oncol Biol
       Phys 2004; 59(4):1116-21
7.     Degen JW, Gagnon GJ, Voyadzis JM et al. CyberKnife stereotactic radiosurgical treatment
       of spinal tumors for pain control and quality of life. J Neurosurg Spine 2005; 2(5):540-9.
8.     Gerszten PC, Burton SA, Ozhasoglu C et al. Radiosurgery for spinal metastases: clinical
       experience in 500 cases from a single institution. Spine 2007; 32(2):193-9.
9.     Gerszten PC, Ozhasoglu C, Burton SA et al. CyberKnife frameless stereotactic
       radiosurgery for spinal lesions: clinical experience in 125 cases. Neurosurgery 2004;
10.    Hof H, Muenter M, Oetzel D et al. Stereotactic single-dose radiotherapy (radiosurgery) of
       early stage nonsmall-cell lung cancer (NSCLC). Cancer 2007; 110(1):148-55.
11.    Kondziolka D, Patel A, Lunsford LD et al. Stereotactic radiosurgery plus whole brain
       radiotherapy versus radiotherapy alone for patients with multiple brain metastases. Int J
       Radiat Oncol Biol Phys 1999; 45(2):427-34.
12.    Lindvall P, Bergstrom P, Lofroth PO et al. Hypofractionated conformal stereotactic
       radiotherapy for arteriovenous malformation. Neurosurgery 2003; 53(5):1036-43.
13.    Madsen BL, Hsi RA, Pham HT et al. Stereotactic hypofractionated accurate radiotherapy
       of the prostate (SHARP), 33.5 Gy in five fractions for localized disease: first clinical trial
       results. Int J Radiat Oncol Biol Phys 2007; 67(4):1099-105.
14.    Meijer OW, Vandertop WP, Baayen JC et al. Single-fraction vs. fractionated LINAC-based
       stereotactic radiosurgery for vestibular schwannoma: a single-institution study. Int J
       Radiat Oncol Biol Phys 2003; 56(5):1390-6.
15.    Mendez Romero A, Wunderink W, Hussain SM et al. Stereotactic body radiation therapy
       for primary and metastatic liver tumors: a single institution phase i-ii study. Acta Oncol
       2006; 45(7):831-7.
16.    Plathow C, Schulz-Ertner D, Thilman C et al. Fractionated stereotactic radiotherapy in
       low-grade astrocytomas: Long-term outcome and prognostic factors. Int J Radiat Oncol
       Biol Phys 2003; 57(4):996-1003.
17.    Raizer J. Radiosurgery and whole-brain radiation therapy for brain metastases: either or
       both as the optimal treatment. JAMA 2006; 295(21):2535-6.
18.    Regis J, Bartolomei F, Rey M et al. Gamma knife surgery for mesial temporal lobe
       epilepsy. J Neurosurg 2000; 93(suppl 3):141-6.
19.    Schrottner O, Eder HG, Unger F et al. Radiosurgery in lesional epilepsy: brain tumors.
       Stereotact Funct Neurosurg 1998; 70(suppl 1):50-6.
20.    Svedman C, Sandstrom P, Pisa P et al. A prospective phase II trial of using extracranial
       stereotactic radiotherapy in primary and metastatic renal cell carcinoma. Acta Oncol
       2007; 45(7):870-5.

Medical Policy                                                                        16 of 18
Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

21.       TEC Assessments 1998; Tab 28.
22.       Timmerman RD, Park C, Kavanagh BD. The North American experience with stereotactic
          body radiation therapy in non-small cell lung cancer. J Thorac Oncol 2007; 2(7 suppl
23.       Weltman E, Salvajoli JV, Brandt RA et al. Radiosurgery for brain metastases: a score
          index for predicting prognosis. Int J Radiat Oncol Biol Phys 2000; 46(5):1155-61.
24.       Whang CJ, Kwon Y. Long-term follow-up of stereotactic Gamma Knife radiosurgery in
          epilepsy. Stereotact Funct Neurosurg 1996; 66(suppl 1):349-56.
25.       Yu C, Chen JC, Apuzzo ML et al. Metastatic melanoma to the brain: prognostic factors
          after gamma knife radiosurgery. Int J Radiat Oncol Biol Phys 2002; 52(5):1277-87.

Index / Cross Reference of Related BSC Medical Policies
The following Medical Policies share diagnoses and/or are equivalent BSC Medical Policies:
      •    Charged-Particle (Proton or Helium Ion) Radiation Therapy
      •    Intensity Modulated Radiation Therapy (IMRT)
      •    Robotically-Assisted Surgery and Robotic Surgical Systems

Key / Related Searchable Words
      •    Cyberknife
      •    GammaKnife
      •    Helium Ion Radiosurgery
      •    IMRT (Intensity Modulated Radiation Therapy)
      •    LINAC
      •    Linear accelerator radiosugery
      •    Proton Beam Radiosurgery
      •    SRS
      •    Stereotactic Radiosurgery
      •    Stereotactic Radiotherapy

Policy History
This section provides a chronological history of the activities, updates and changes that have
occurred with this Medical Policy.

  Effective Date          Action                                          Reason

Medical Policy                                                                      17 of 18
Medical Policy: Stereotactic Radiosurgery and Stereotactic Radiotherapy
Original Policy Date: 2/26/1992
Effective Date: 7/07/2008

  Effective Date          Action                                          Reason

  02/26/1992              Policy Adopted                                  Medical Policy Committee

  12/7/2006               Policy revision to include additional           BCBSA TEC guideline on
                          BCBSA TEC guideline for refractory              Refractory Trigeminal Neuralgia
                          trigeminal neuralgia

  01/30/2008              Disclaimer statement added to policy            Administrative Update

  05/16/2008              Policy revision-BCBSA MPP adoption              Medical Policy Committee
                          New description, defined policy
                          criteria, Coding updated. Title changed
                          from, Stereotactic Radiosurgery to
                          Stereotactic Radiosurgery and
                          Stereotactic Radiotherapy

  07/07/2008              Policy revision- Extended medical               Medical Policy Committee
                          necessity criteria to extracranial sites.

The materials provided to you are guidelines used by this plan to authorize, modify, or deny care
for persons with similar illness or conditions. Specific care and treatment may vary depending on
individual need and the benefits covered under your contract. These Policies are subject to
change as new information becomes available.

Medical Policy                                                                               18 of 18

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