Transcript of Prof. S. Deivanayagam MS Professor & HOD of Surgery Madras Medical College Carcinoma of Thyroid.
- Slide 1
- Prof. S. Deivanayagam MS Professor & HOD of Surgery Madras
Medical College Carcinoma of Thyroid
- Slide 2
- Ca. Thyroid - Types : - Primary / secondary Follicular
cell-derived Papillary thyroid cancer Follicular thyroid cancer
Anaplastic thyroid cancer Lymphocyte derived Lymphoma C-Cell
derived Medullary thyroid cancer Secondary breast, colon,
melanoma
- Slide 3
- Differentiated Thyroid Ca. : - 85% of all thyroid cancers
Derived from follicular cells Types Papillary carcinoma Follicular
carcinoma Mixed Papillary Follicular Hurthle cell carcinoma
- Slide 4
- Etiology & Risk factors : - Male sex Previous neck
irradiation For Hodgkins lymphoma Papillary ca. Pre-existing
lesions MNG Follicular ca. Hashimotos Papillary ca. (controversial)
Iodine deficiency Follicular ca Family H/O Familial Syndromes
- Slide 5
- Familial Non-Medullary Thyroid ca : -
- Slide 6
- Clinical Features : - MC presentation Painless swelling in the
neck Pain Dysphagia Stridor Rapid enlargement Hoarseness of voice
(most important) Dyspnoea, Hemoptysis (late & rare) Lateral
aberrant thyroid lymphnode mets in papillary ca. thyroid Pulsatile
bony secondaries in follicular thyroid ca.
- Slide 7
- Papillary Thyroid Ca. : - Most common type (~80%) Young females
(mean age 30 - 40 yrs) Least malignant one of the curable
malignancies Commonly metastasize to neck nodes Distant metastasis
uncommon Minimal or occult/microcarcinoma refers to tumours of 1 cm
or less in size with no evidence of local invasiveness through the
thyroid capsule or angioinvasion, and that are not associated with
lymph node metastases
- Slide 8
- PTC Neck secondaries : -
- Slide 9
- PTC Types : - Types Follicular variant Tall cell Columnar cell
Diffuse sclerosingPoor Prognosis Insular Breaking of capsule
- Slide 10
- PTC Pathology : - Gross : - Multi-focal Unencapsulated but
often has pseudocapsule Microscopic : - Closely packed Papillae
Psammoma bodies Oval or elongated pale staining nuclei with ground
glass appearance Orphan Annie eye cells
- Slide 11
- Papillae : -
- Slide 12
- Psammoma bodies : -
- Slide 13
- Orphan Annie Cells : -
- Slide 14
- Orphan Annie : -
- Slide 15
- Investigations : - USG neck To identify the lesion To
categorize the nodule To detect associated lymphadenopathy To take
guided FNAC FNAC Best first line diagnostic procedure for papillary
ca. Thyroid function test
- Slide 16
- PTC Prognostic Systems : - AGES Age, Grade, Extent & Size
AMES Age, Mets, Extent & Size GAMES Grade, Age, Mets, Extent
& Size FactorsLow RiskHigh Risk Age40 yrs SexFemaleMale
ExtentIntrathyroidalExtrathyroidal MetastasisNonePresent Size4 cm
GradeWell differentiated Poorly differentiated
- Slide 17
- PTC Prognostic Systems : - DeGroots classification Class I
Intra-thyroidal Cass II Cervical node mets Class III
Extra-thyroidal invasion Class IV Distant mets Most important
prognostic factor Age at diagnosis Lymph node mets No prognostic
significance
- Slide 18
- Follicular Thyroid Ca. : - Accounts for ~10% of thyroid ca.
Common in females Mean age 40 50 yrs Common in iodine deficient
areas May coexist with MNG Metastasize to flat bones pulsatile bony
secondaries Lymph node metastasis uncommon
- Slide 19
- FTC Bone Mets : -
- Slide 20
- FTC Types : - Minimally invasive Capsular invasion without
involvement of surrounding parenchyma and vascular invasion (except
those within tumour) Widely invasive Surrounding parenchymal and /
or vascular invasion
- Slide 21
- FTC Pathology : - Gross Solitary & Encapsulated Microscopic
Well differentiated cells Presence of Vascular and / or capsular
invasion FNAC & frozen section cannot distinguish between
follicular adenoma & carcinoma Minimal tissue required -
Hemithyroidectomy
- Slide 22
- FTC Capsular Invasion : -
- Slide 23
- TNM Classification : - Common for all differentiated thyroid
carcinomas The only TNM system to incorporate the age of the
patient Separate for differentiated, medullary and anaplastic
ca.
- Slide 24
- TNM for DTC AJCC 7 th : - T1Tumour 2cm or less & confined
to thyroid T2Tumour 2 4 cm & confined to thyroid T3 Tumour
>4cm or minimal extra-thyroid extension (Invasion of
sternothyroid/perithyroid soft tissues) T4aInvasion of larynx,
trachea, oesophagus or RLN T4bInvasion of prevertebral fascia or
carotid a.
- Slide 25
- TNM for DTC AJCC 7 th : - N1aMetastasis to level VI nodes N1b
Involvement of unilateral/bilateral lateral group nodes(level I -
V) or mediastinal nodes (level VII) M0No distant metastasis
M1Distant metastasis
- Slide 26
- TNM Stage Grouping : - AGE < 45 years IAny TAny NM0 IIAny
TAny NM1
- Slide 27
- TNM Stage Grouping : - AGE > 45 years IT1N0M0 IIT2N0M0 IIIT1
T3N1aM0 IVT4a / T4bN1bM1
- Slide 28
- DTC - Treatment : - Surgery remains the main stay of treatment
for DTC Types of Surgeries : - Total thyroidectomy Removal of all
thyroid tissue with preservation of parathyroids Total
thyroidectomy remains Gold standard
- Slide 29
- Total thyroidectomy Rationale : - Total thyroidectomy Pros : -
Enables usage of RAI effectively Makes serum Tg a sensitive marker
for recurrence Enables better removal of central compartment nodes
Reduces the risk of recurrence Reduces the risk of re-operation
Total thyroidectomy Cons : - Risk of RLN injury &
hypocalcemia
- Slide 30
- Node management in DTC : - Without lateral group enlargement
Total thyroidectomy with central compartment node dissection With
unilateral lateral group nodes mets Total thyroidectomy with MRND
With b/l lateral group nodes mets Total thyroidectomy with b/l MRND
Prophylactic neck dissection NOT indicated
- Slide 31
- Post-op 131 I adjuvant therapy : - Specific uptake into
follicular cells Emits both particles and rays rays are therapeutic
while particles produce radiation toxicity Indications : - Positive
radio-iodine uptake scan post total thyroidectomy
- Slide 32
- 131 I ablation continued Precautions : - Stop thyroxine for 4-6
wks TSH > 30-50 mU/L for maximal effect Avoid iodinated contrast
CTs, salts & pain balms Therapeutic dose : - Low risk pt.
30-100mCi High risk pt. 100-200mCi
- Slide 33
- Role of Chemo & Radiotherapy : - Radiotherapy - Indications
: - Unresectable disease Metastasis in support bones to avoid
fractures Painful metastasis No role for routine chemotherapy
Doxorubicin is commonly used mainly as a radiation sensitizer
- Slide 34
- Post-op follow up : - Suppressive dose of thyroxine till TSH
95% 10yr relapse free survival Subsequent scans only if clinically
indicated Thyroglobulin : - Level >2ng/ml suggestive of
recurrence / mets Tg & anti-Tg antibodies level should be
measured every 6mth in first year, and then annually
- Slide 35
- Hurthle Cell Ca. : - Variant of Follicular cell ca. Women >
Men Affects older age group ~65 yrs Defn. - An encapsulated group
of follicular cells with at least a 75% Hurthle cell or Oncocyte
component Large, polygonal, eosinophilic thyroid follicular cells
with abundant granular cytoplasm and numerous mitochondria -
Askanazy
- Slide 36
- Hurthle Cell Ca : -
- Slide 37
- Hurthle Cell Ca. continued..: - Often multicentric Diagnosis
requires demonstration of capsular and / or vascular invasion
Regional lymph nodes involved ~30% & is a poor prognostic
indicator Distant metastasis in ~15% More aggressive & poorer
prognosis
- Slide 38
- Hurthle cell ca. Treatment : - Total thyroidectomy &
central compartment node dissection recommended MRND done in case
of enlarged lateral nodes Post op management : - Thyroid
suppression Serum thyroglobulin measurement every 6 months
Postoperative radioactive iodine is usually not effective (10%
concentrate iodine)
- Slide 39
- Medullary Carcinoma : - Arises from Para-follicular C cells
from neural crest Constitutes 3 10 % of all thyroid cancers Types
Sporadic Hereditary (Familial or MEN II)
- Slide 40
- Clinical features: - Symptoms due to the tumour Both lymphatic
& hematogenous spread common Paraneoplastic Syndromes Due to
secretion of calcitonin, VIP, serotonin and somatostatin Diarrhoea
most common
- Slide 41
- Medullary Ca. - Peculiarities : - Characteristic amyloid stroma
on HPE Doesnt take up radioactive iodine Both I-131 scan and
radio-iodine ablation are of no use Serum calcitonin elevation
tumour marker Presence of lymph node metastasis is a poor
prognostic indicator
- Slide 42
- Investigations : - FNAC USG / CT neck Calcitonin confirms the
diagnosis CEA (>50% of tumours) USG abdomen & 24hr urine
catecholamines to rule out pheochromocytoma
- Slide 43
- Amyloid Stroma : -
- Slide 44
- Treatment : - Without neck nodes Total thyroidectomy with
central compartment neck dissection With neck nodes Total
thyroidectomy with MRND of the involved side External beam RT
Extra-thyroidal extension(T4 disease) Unresectable / metastatic
disease as palliation Follow up serum calcitonin & CEA
monitoring
- Slide 45
- Anaplastic Carcinoma : - Most aggressive and fortunately rarest
variety Invariably well advanced at presentation Worst prognosis
Treatment Palliative External beam RT Surgery isthumusectomy to
relieve tracheal obstruction
- Slide 46
- Carry Home Message : - DTC carries very good prognosis and when
detected early is a curable disease Total thyroidectomy with
central node dissection is the gold standard treatment in both DTC
& MTC MRND is optional RAI ablation plays a key role in
metastatic disease in DTC
- Slide 47
- Thank You