A 40 year old female presents with swelling in the neck. O/E it is a 2x2 cm nodule on the right lobe of thyroid. No palpable cervical nodes. FNAC shows features of papillary carcinoma. Treatment of choice
Answer: a) Total thyroidectomy (SABISTON 19TH ED, P-908)PAPILLARY CARCINOMA (80%)Most common type of thyroid carcinomaMore common in womenMostly in the age group 25 - 50Mutations in RET or BRAF geneAssociated with previous exposure to ionizing radiationHistologyNuclei: optically clear or empty appearance - groundglass or Orphan Annie eye nucleiCrowded nuclei may demonstrate groovingPsammoma bodiesSeldom encapsulatedMultiple foci seenHistologic variants - follicular (mc), tall cell, diffuse sclerosing, insular, columnarSlowly progressive and less aggressive tumorThyroglobulin is used as tumor markerSpread to lymph nodes is common, blood borne metastasis is unusualLymph node status does not alter the prognosisSeen as cold masses on scintiscansClassic papillary carcinoma and follicular variant - Excellent prognosisAll other subtypes - aggressiveDiffuse sclerosing variantOccurs in younger individuals, including childrenExtensive, diffuse fibrosis throughout the thyroid glandOften associated with a prominent lymphocytic infiltrate, simulating Hashimoto thyroiditisLack BRAF mutations, but RET/PTC translocations are found in 50% casesMicrocarcinoma (Occult carcinoma)Papillary cancers less than 1 cmMost commonly come to attention as an incidental finding in patients undergoing surgeryMajority of such tumours never progress to become a clinically significant entityHave a uniformly excellent prognosisFactors associated with worse prognosisMale genderAge > 40 yarsSize > 3 cmTall cell variantAge at diagnosis - most important prognostic factor in well-differentiated thyroid cancer Treatment of differentiated thyroid cancerSolitary intrathyroidal papillary microcarcinoma: no clinically involved cervical lymph nodes, no history of head and neck radiation - unilateral thyroid lobectomy and isthmusectomyTumors > 1 cm with no palpable nodes: Total thyroidectomyTumors > 2 cm with nodal involvement and/or metastases: Total thyroidectomy + node dissection + radioiodine ablation + long term TSH suppressionThyroid cancer > 1 cm or papillary cancer < 1 cm: clinically positive nodal disease, multicentricity, or a history of head and neck radiation - total or near-total thyroidectomy, followed by radioablationTSH suppression: thyroxine 0.1- 0.2 mg daily for all patients after operation for differentiated thyroid carcinoma on the basis that most tumours are TSH dependent.
Total thyroidectomy
Right hemithyroidectomy
Hartley-Dunhill operation
Subtotal thyroidectomy
Thyroid Gland