Soft Tissue Sarcomas by MikeJenny


									Soft Tissue Sarcomas

         July 25, 2011

   Rare: only 8300 new cases annually in U.S.
   3900 die annually from STS
   Mesodermal origin
Location and Type

   h/o Radiation therapy increases grade of tumors and
    risk for metastasis
   Chemical exposure
           Thorotrast, vinyl chloride, arsenic for hepatic angiosarcoma
   Genetic syndromes
           Neurofibromatosis – nerve sheath tumors
           Familial gastrointestinal stromal tumor syndrome – KIT
                     Skin hyperpigmentation, uticaria, cutaneous mast cell dx
   Soft tissue and bone
            viscera (gastrointestinal, genitourinary, and gynecologic organs)
            nonvisceral soft tissues (muscle, tendon, adipose, pleura, and
             connective tissue)
   By differentiation (usually with IHC staining)
            adipocytic tumors
            fibroblastic/myofibroblastic tumors
            fibrohistiocytic tumors
            smooth muscle tumors
            pericytic (perivascular) tumors
            primitive neuroectodermal tumors (PNETs)
            skeletal muscle tumors
            vascular tumors
            osseous tumors
            tumors of uncertain differentiation

   Most present as painless mass leading to delayed
    diagnosis as lipoma or hematoma
   Core needle biopsy guided by palpation or by image
    guidance if not palpable
           Few cases of tumor seeding with closed biopsy so some
            recommend tattooing site for later excision with specimen
   Excisional biopsy for superficial small lesions if
    needle biopsy non-diagnostic
   Incision biopsy
           Longitudinal incision without tissue flaps with meticulous
            hemostasis to prevent tumor seeding in hematomas
           Send biopsy fresh and orientated
Tumor seeding after biopsy

   MRI
          For extremity masses
          Gives good delineation between muscle, tumor and
           blood vessels
   CT for abdominal and retroperitoneal
   PET
          May help determine high vs. low grade
          May be helpful in recurrences

   AJCC/UICC Staging System for Soft Tissue Sarcomas
           T1: <5cm
              –   T1a: superficial to muscular fascia
              –   T1b: Deep to muscular fascia
           T2: >5cm
              –   T2a: superficial to muscular fascia
              –   T2b: Deep to muscular fascia
           N1: Regional nodal involvement
           Grading
              –   G1:   Well-differentiated
              –   G2:   Moderately differentiated
              –   G3:   Poorly differentiated
              –   G4:   Undifferentiated

Stage IA         G1,2          T1a,b          N0             M0
Stage IB         G2,2          T2a,b          N0             M0
Stage IIA        G3,4          T1a,b          N0             M0
Stage IIB        G3,4          T2a            N0             M0
Stage III        G3,4          T2b            N0             M0
Stage IV         Any G         Any T          N1             M1
Staging system predicts survival and risk of metastasis, but not local recurrence
**Does not take into account extremity vs. visceral
Survival by stage
Relative risk for recurrence and

   Age >50 years                      1.6
   Local recurrence at presentation   2.0
   Microscopically positive margin    1.8
   Size 5.0–10.0 cm                   1.9
   Size > 10.0 cm                     1.5
   High-grade                         4.3
   Deep location                      2.5
   Local recurrence                   1.5

   Limb-sparing vs amputation
          Comparison study with post-op radiation in limb sparing
           showed no difference in survival
   Amputation still may be indicated for
    neurovascular or bone involvement

   Arbitrary 2 cm margin if no plan for post-op
   Negative margins may be adequate for post-
    op radiation therapy
          Presence of positive margins increases local recurrence
           by 10-15%
   No need for lymph node dissection as only 2-
    3% have nodal metastasis
Adjuvant radiotherapy

   Small, low grade tumors resected with 2 cm
    margins may not require radiation
   Improves local control but not survival
   Whether improved local control leads to
    improved survival is controversial
Local recurrence with post-op
Pre-op or post-op radiation?

   Some avoid pre-op use because of
    increased wound complications (although
    this is debatable)
          RCT looking at wound complication rate pre-op vs post-
           op radiation showed 35% vs 17%
                    Risk confined to lower extremity
          Conclusions: pre-op may be better for upper extremity
           and head & neck because of equal wound complication
           risk and benefit of lower radiation doses to more vital
Pre-op vs post-op radiotherapy

   Can improve local control, but not survival
   Doxorubicin and ibosfamide have response
    rates of 20%
   Use only in advanced disease
   Combination with radiation or neoadjuvant
    therapy are controversial
   Hypothermic isolated limb perfusion may be
    used for palliation
Treatment of Recurrence

   20-30% of STS patients will recur
   More common in retroperitoneal and head &
    neck high grade tumors because hard to get
    clear margins
          38% for retroperitoneal
          42% for head and neck
          5-25% for extremity
   After re-resection recurrence is 32% for
    extremity and much higher for visceral
Metastatic disease

   Lung most common site of mets, but visceral
    often go to liver
   Median survival from development of
    metastatic disease is 8-12 months
   Resection of pulmonary mets can give 5 year
    survival of 32% if all mets can be removed
          >3 mets is poor prognosticator
Case #1

   64 y/o male with increasing abdominal girth
Retroperitoneal Sarcomas

   15% of all sarcomas
   Liposarcoma 42% and leiomyosarcoma 26%
   CT scan can show cystic/solid/necrotic components and
    relation to surroundings
   CXR to r/o mets, chest CT if CXR abnormal
   Biopsy not necessary unless suspect a lymphoma or germ cell
    tumor or plan preop chemo or radiation
   En bloc resection is standard treatment
           bowel prep
           assess bilateral kidney function
           50-80% need organ resection
           78% of primary lesions can be completely resected
Survival after resection of primary
retroperitoneal sarcoma
Prognosis for retroperitoneal

   5 year survival after complete resection of
          Drops to 10-36% if incompletely resected
   Recurrence occurs in 46-59% of completely
    resected tumors
Radiation or chemotherapy for
retroperitoneal sarcomas

   Radiation
    –   GI and neurotoxicities limit delivery of sufficient
    –   May improve local control
    –   Recommended for use only in clinical trials given
        lack of data either way
   Chemotherapy
    –   Use for recurrent, unresectable or metastatic
 Case #2
• 49 y/o female with GERD undergoing EGD

   Separate subtype of sarcoma defined by expression
    of c-Kit (CD117)
   Surgery: complete resection without local or regional
   Very resistant to traditional chemotherapy
   Gleevec (imantinib mesylate)
           c-Kit is constitutively active tyrosine kinase receptor
           Drug is tyrosine kinase inhibitor used in CML
           Initial studies showed 54% response rates
           Two RCTs currently looking at adjuvant treatment
Extremity sarcomas

                     Synovial sarcoma

Breast sarcomas

   1% of all breast neoplasms
   Wide excision with negative margins
   No clear role for adjuvant radiotherapy
Sarcoma after mastectomy
Vascular sarcomas

   Angiosarcoma, hemangiosarcoma,
    lymphangiosarcoma, hemangiopericytoma
   Key points:
          Hepatic angiosarcoma – thorotrast, vinyl chloride,
          Stewart Treve’s – lymphangiosarcoma in chronic
   High risk for bleeding during excision
   No clear role for chemo or radiation

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