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					 CLINICAL AND SONOGRAFIC APPROACH TO
          THE THYROID NODULE




Department of Internal Medicine
     and Gastroenterology
     University of Bologna

     L. Bolondi, L. Rasciti
              Caso clinico
• Donna di 56 anni, sposata con 3 figli, in
  menopausa da 5 anni.
• Si accorge, guardandosi allo specchio, di
  lieve asimmetria della circonferenza del
  collo (modica tumefazione a sin);
• Il medico palpa una formazione nodulare, di
  consistenza parenchimatosa, non dolente,
  verosimilmente riferibile al lobo tiroideo
  sin. Non rileva linfoadenopatie.
              Caso clinico
• Funzione tiroidea (FT3, FT4, TSH) nella
  norma
• Autoanticorpi (anti TG, antimicrosomiali)
  nella norma
• Emocromocitometrico, GOT, GPT,
  Azotemia, Glicemia, Protidemia totale ed
  elettroforesi, VES, Es; urine nella norma
• Viene inviata per esame ecografico
NODULO ISOECOGENO
 CON AREA LIQUIDA
     INTERNA.
AL DOPPLER SEGNI DI
VASCOLARIZZAZIONE
    PERIFERICA
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

Key concepts


• Thyroid nodules are the most common
  endocrine disorder, they can be detected
  in an otherwise normal gland, especially in
  iodine-deficient areas. The frequency of
  thyroid nodules increases throughout life.


• Single nodules are about four times more
  common in women than in men.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE




Key concepts
• Nodules are 10
  times more
  frequent, in
  comparison to
  palpation, when the
  gland is examined
  at autopsy, during
  surgery, or by
  ultrasonography.          Prevalence of palpable thyroid nodules detected
                            at autopsy or by ultrasonography (solid circle) or
                            by palpation (open square) in subjects without
                            radiation exposure or known thyroid disease.
                                                           E. Mazzaferri, NEJM 1993
TIROIDE NORMALE
NORMAL THYROID: Right lobe
TIROIDE: VASCOLARIZZAZIONE
ARTERIA TIROIDEA SUPERIORE
 Small (<5mm) non
  palpable thyroid
nodule in the left lobe
(occasional finding)
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

Key concepts
• Less than 1% of thyroid nodules detected at US
  prove to be malignant.
• Less than 5% of solitary nodules detected at US
  are malignant.
• A significant number of elderly patients have
  clinically silent thyroid cancers: up to 35% of
  thyroid glands at autopsy contain tiny (<1.0 cm),
  clinically unimportant papillary carcinomas.
• Among nodules removed surgically, an estimated
  42 to 77 % are non-neoplastic colloid nodules, 15
  to 40 % are adenomas, and 8 to 17 % are
  carcinomas.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


CLASSIFICATION OF THYROID NODULES

Benign Nodules
a) Hyperplastic (colloid) nodule within goiter
b) Follicular Adenoma
         i. Colloid variant
         ii. Hurthle cell variant
c) Papillary Adenoma (suspect for
           malignancy)
d) Teratoma
    CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


•     Hyperplastic and Colloid (adenomatous)
      nodules are the dominant type of nodules,
      and can be single or multiple.
•     Most      are      hypofunctioning      and
      incompletely    encapsulated.      Cytologic
      studies usually reveal abundant colloid
      and    benign     follicular   cells,    but
      hemorrhagic nodules or highly cellular
      aspirates     may      be    difficult    to
      differentiate from follicular cancer.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

• A diagnosis of a follicular or Hürthle cell tumor
  requires further evaluation and management, since
  the cytologic features of benign follicular or
  Hürthle cell tumors and low-grade follicular or
  Hürthle cell cancer are similar.
• Benign from malignant nodules can only be
  distinguished by the presence or absence of
  capsular or vascular invasion on histologic
  examination of surgical specimens.
• Follicular and Hürthle cell tumors have
  respectively a malignancy rate of 10% to 20%,
  that cannot generally be assessed adequately at
  FNAB .
CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

Malignant Nodules
a)   Papillary Carcinoma (75-85%)
       i. Pure papillary
       ii. Mixed papillary and follicular carcinoma
b)   Follicular Carcinoma (20-25%)
       i. Malignant adenoma
       ii. Hurthle cell carcinoma or oxyphil
            carcinoma
       iii. Clear-cell carcinoma
c)   Medullary Carcinoma (5%)
d)   Anaplastic Carcinoma (<5%)
e)   Lymphoma
f)   Metastatic tumor
   CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE



Nodules with sonographic apparence of cysts
• Fifteen to 25 percent of all thyroid nodules
  are cystic.
• High-resolution ultrasound has shown that
  most of the nodules initially considered to be
  cystic are complex lesions (solid-cystic).
• Up to 15 percent are necrotic papillary
  cancers, and about 30 percent are
  hemorrhagic adenomas.
NODULE WITH CYSTIC APPEARANCE
HAEMORRHAGIC CYST
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

        Dectection of thyroid nodules
• By chance during routine physical
  examination
• By chance during US of the neck
  performed for other problem (i.e. carotid
  arteries, lymphnodes etc.)
• In symptomatic patiens: local pain
                          tenderness
                          swelling
                          dysphagia
                          dysphonia
                          hoarseness
    CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE



Clinical challenge: to identify which nodules
                    are malignant

•     History and physical examination
•     Laboratory evaluation
•     Radionuclide scanning
•     Ultrasonography
•     FNA biopsy
•     UG-FNA biopsy
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

Clinical elements for differential diagnosis

            Benign                           Malignant
• Family history of benign           • A family history of
  thyroid nodule or goiter or          medullary or papillary
  autoimmune thyroid
                                       thyroid cancer or of
  disease.
                                       familial polyposis
• Symptoms of                          (Gardner's syndrome).
  hypothyroidism or
  hyperthyroidism.            • Age—the young (<20 years
                                old) and the old (>70 years
• Pain or tenderness
  associated with the nodule.   old) have the highest
                                incidence of thyroid
                                cancer.
    These factors do not exclude
   the presence of thyroid cancer.   • Rapid tumor growth.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

Clinical elements for differential diagnosis

           Benign                     Malignant
• Soft, smooth, mobile        • Gender—the proportion of
  nodule.                       nodules that are malignant
• Multinodular goiter without   in males is double that in
  a dominant nodule.            females.
                              • Nodule plus dysphagia or
                                hoarseness.
                              • Firm, hard, irregular, and
                                fixed nodule.
                              • Presence of cervical
                                lymphadenopathy.
 These factors do not exclude the
     presence of thyroid cancer.
CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

Clinical elements for differential diagnosis

        Benign                      Malignant
                           • History of external
                             neck irradiation during
                             childhood or
                             adolescence (this
                             factor also increases
                             the incidence of
                             nonmalignant thyroid
                             nodular disease) or
                             exposure to nuclear
                             fallout.
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


              Laboratory evaluation
• In patients with a thyroid nodule, a sensitive
  thyroid stimulating hormone (TSH) assay
  should be done, at a minimum, to determine
  the presence of hyperthyroidism or
  hypothyroidism.
• Serum calcitonin should be measured when
  medullary thyroid carcinoma or MEN II is
  suspected.
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


               Radionuclide scanning
• Aim:       to identify hyperfunctioning nodules
             that are almost always benign.
Limits:      lack of differentiating criteria for
                  hypofunctioning nodules


 Not all patients with thyroid
         nodules require nuclear imaging.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


                 Ultrasonography
• Widespread use of ultrasound for examining any
  neck pathology has resulted in frequent
  recognition of thyroid nodules, that are too small
  to be palpated on clinical examination.
• Usually, such nodules are < 1cm in largest
  diameter, they are typically asymptomatic, and are
  not associated with lymph nodes or other
  suggestions of malignancy.
• Often incidentally found, such nodules produce a
  problem because of the difficulty in achieving a
  specific diagnosis, which is desired by the patient.
    CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

                    Ultrasonography
•   In a recent metanalysis (Ann Intern Med, 126:226-
    31, 1997.), the risk for malignancy in US
    incidentalomas ranged betwen 0.45% and 13%.
•   Large malignant nodules have been reported to be
    missed by palpation. The greatest size of malignant
    non palpable nodules was 2.1 cm.
•   The existence of these nodules, detected by US
    exploration, suggests that a simple follow-up neck
    palpation, may not be the safest management
    strategy.
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

                  Ultrasonography
• Currently no ultrasound criteria can
  distinguish benign from malignant thyroid
  nodules. However some features are
  suggestive for malignancy:
      a) Microcalcification
      b) Irregular or microlobulated margin
      c) Hypoechogenicity
      d) Intranodular blood flow pattern
NODULO ISOECOGENO
 CON AREA LIQUIDA
     INTERNA.
AL DOPPLER SEGNI DI
VASCOLARIZZAZIONE
    PERIFERICA
HYPERPLASTIC THYROID NODULE
TIROIDE: NODULO IPERPLASTICO
TIROIDE: NODULO
  IPERPLASTICO
TIROIDE: NODULO PARZIALMENTE CISTICO
         CON CALCIFICAZIONI
MEDULLARY CARCINOMA
 PAPILLARY CARCINOMA
Intranodular Vascularization
FOLLICULAR CARCINOMA
MORBO DI BASEDOW
TIROIDITE
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

                     FNA biopsy
• FNAB has become the initial test, after
  clinical and/or US examination, because it is
  safe and inexpensive and leads to a better
  selection of patients for surgery.
• FNAB is now believed to be the most
  effective method available for distinguishing
  between benign and malignant thyroid
  nodules.
• In this setting the FNAB sensitivity varies
  from 68 to 98% (mean, 83%) and specificity
  varies from 72 to 100% (mean, 92%).
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

                     FNA biopsy
• Provided that an adequate specimen is
  obtained, three cytologic results are
  possible:    benign,       malignant,   and
  indeterminate (or suspicious) findings.
• A major problem diminishing the potential
  benefit of FNAB is the unskilled physician
  performing the biopsy or the inexperienced
  cytopathologist interpreting the specimens.
• Even in skilled hands, however, approximately
  10% of biopsy findings are nondiagnostic.
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

                     FNA biopsy
• Repeated FNAB may be appropriate under
  several circumstances as follows: (1) when
  the lesion continues to enlarge; (2) when new
  clinical features develop that suggest
  possible malignancy; (3) when the previous
  cytologic diagnosis was indeterminate, or (4)
  when there is insufficient material for
  cytologic diagnosis.
• Routine repetitive FNAB of lesions that were
  previously shown to be benign is rarely
  indicated.
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


                  UG-FNA biopsy
• Ultrasound-guided FNAB (UG-FNAB) has
  emerged as an alternative to conventional
  FNAB for the diagnostic evaluation of
  nonpalpable nodules and for the repeat
  evaluation   of  nodules  with   previous
  nondiagnostic FNAB.
• It is also an excellent method for the
  evaluation of complex nodules by precisely
  positioning the needle in the solid portion of
  these nodules.
FNAB OF SOLID THYROID NODULE
  The arrow points to the needle
  CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

                  UG-FNA biopsy
• In the literature, the sensitivity and specificity of
  UG-FNAB amounted to 79% and 85%, respectively.
• UG-FNAB is possible for lesions smaller than 1 cm in
  size, but considering the probable benign nature of
  most of such lesions, a common alternative course is
  "observe" such lesions periodically.
• Due to the high prevalence of US thyroid nodules, a
  systematic UG-FNAB performed on all nonpalpable
  nodules is not advisable.
         CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

PALPABLE THYROID NODULE          ULTRASONOGRAPHY                    NOT PALPABLE THYROID NODULE




                 YES            SINGLE NODULE  1 cm
INCREASED RISK                                             NO
                                         or
                                 DOMINANT NODULE
   NO
                                                           YES                         NO
                                       YES                       INCREASED RISK


                                 NO                 YES
                 NO
  TSH < 0.03                              CYST
                                                                        YES         US SIGNS      NO
                                                                                 FOR MALIGNANCY
   YES
                                FNAB             UG-FNAB
                                                                  NO                        YES
                 NO                                                      COLD NODULE
 HOT NODULE

                               YES                   NO
   YES                                 DIAGNOSTIC
                      BENIGN
                                                                                 NO


  TREATMENT                      SUSPICIOUS                            INCREASED RISK


           YES    TSH < 0.03                                                     YES
                                 FOLLICULAR LESION
                  TSH > 4.5

                       NO
                                                                       SURGERY
                                     CANCER
                  FOLLOW UP
                  US and LAB
GOZZO COLLOIDOCISTICO TIROIDEO
IPERPLASIA NODULARE
TIROIDE: CA PAPILLIFERO
   CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE




Nodules with sonographic apparence of cysts
• Both benign and malignant lesions may yield
  bloody fluid; clear, amber fluid usually indicates
  a benign lesion.
• Cystic lesions often yield insufficient numbers
  of cells for diagnosis.
TIROIDE: CISTI EMORRAGICA
TIROIDE: VASCOLARIZZAZIONE
TIROIDITE DI HASHIMOTO
TIROIDITE DI HASHIMOTO
META TIROIDEE DI CA LARINGE
TIROIDE: NODULO
  IPERPLASTICO
    CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE




Benign Nodules
• Hyperplastic nodules (within goitre)
• Follicular Adenoma
            •   Colloid variant
            •   Hurthle cell variant
•     Papillary Adenoma (suspect for
              malignancy)
•     Teratoma
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

• Papillary carcinoma is usually recognizable in
  specimens obtained by fine-needle aspiration
  biopsy. The smears tend to be cellular, and the
  cells have large nuclei with a pale ground-glass
  appearance.
• Follicular carcinoma is a tumor most reliably
  identified by invasion of the capsule or of vessels
  by malignant cells in surgical specimens (difficult
  diagnosis at fine-needle aspiration biopsy).
• Medullary     and    Anaplastic    carcinomas and
  Lymphomas (a particular risk in patients with
  Hashimoto's disease) can ordinarily be identified
  by fine-needle aspiration biopsy.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

• A diagnosis of a follicular or Hürthle cell tumor
  requires further evaluation and management, since
  the cytologic features of benign follicular or
  Hürthle cell tumors and low-grade follicular or
  Hürthle cell cancer are similar.
• Benign from malignant nodules can only be
  distinguished by the presence or absence of
  capsular or vascular invasion on histologic
  examination of surgical specimens.
• Follicular and Hürthle cell tumors, diagnosed by
  using FNAB, have respectively a malignancy rate
  of 10% to 20%, that cannot generally be assesed
  at FNAB .
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE



• Macrofollicular adenomas have no malignat
  potential
• Although macrofollicular colloid adenomas have no
  malignant potential, about 5 percent of
  microfollicular adenomas, 5 percent of Hurthle-
  cell adenomas, and 25 percent of embryonal
  adenomas are follicular cancers.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

• A diagnosis of a follicular or Hürthle cell tumor
  requires further evaluation and management, since
  the cytologic features of benign follicular or
  Hürthle cell tumors and low-grade follicular or
  Hürthle cell cancer are similar.
• Benign from malignant nodules can only be
  distinguished by the presence or absence of
  capsular or vascular invasion on histologic
  examination of surgical specimens.
• Follicular and Hürthle cell tumors, diagnosed by
  using FNAB, have respectively a malignancy rate
  of 10% to 20%, that cannot generally be assesed
  at FNAB .
    CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE


•     Colloid (adenomatous) nodules are the
      dominant type of nodules, and can be
      single or multiple.
•     Most      are       hypofunctioning     and
      incompletely     encapsulated.     Cytologic
      studies usually reveal abundant colloid
      and     benign    follicular   cells,    but
      hemorrhagic nodules or highly cellular
      aspirates     may      be    difficult    to
      differentiate from follicular cancer.
 CLINICAL AND SONOGRAFIC APPROACH TO THE THYROID NODULE

• Follicular adenomas, which are thought to be
  monoclonal tumors, tend to be single lesions with
  well-developed fibrous capsules and a uniform
  histologic structure distinct from the normal
  surrounding thyroid. They are classified according
  to the size or presence of follicles and the degree
  of cellularity.
• Although macrofollicular colloid adenomas have no
  malignant potential, about 5 percent of
  microfollicular adenomas, 5 percent of Hurthle-
  cell adenomas, and 25 percent of embryonal
  adenomas are follicular cancers.

				
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posted:11/26/2011
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