1. Thyroid cancer is the most common endocrine malignancy, accounting for 1% of all cancers and 0.5-1 cases per 100,000 people. 2. Papillary carcinoma makes up 75-85% of thyroid cancer cases and is usually associated with activation of receptor tyrosine kinases. 3. Differentiated thyroid cancers including papillary and follicular carcinoma have a good prognosis, while anaplastic and medullary carcinomas carry a worse prognosis.

1. Thyroid Cancer Col N Kannan Sr Adv Surgery & Surgical Oncology Army Hospital (R&R) New Delhi

2. Thyroid Cancer Commonest endocrine malignancy 1% of all malignancies 0.5-1 per 100000 Good prognosis Extent of treatment is hotly debated No randomized trials

3. Thyroid cancer 1.5% of all cancer Papillary carcinoma(75-85% of cases) Activation of receptor tyrosine kinases (RET/PTC, TRK, MET) ->Produce chimeric proteins with tyrosine kinase activity Follicular carcinoma(10-20%) Medullary carcinoma(5%) Anaplastic carcinoma(<5%)

4. Classification Differentiated Thyroid Cancer Papillary Cancer (PTC) and its variants Follicular Cancer (FTC) Hurthle cell cancer Anaplastic Cancer MedullarycancerM

5. Presentation Solitary or Multiple thyroid nodules Neck Nodes Hoarse voice of recent onset Mediastinaladenopathy Bone or lung metastasis

6. Important History Radiation to neck / chest MEN syndrome Family history Diarrhoea Adrenal tumour Recent change in a pre-existing goitre Size change/nodularity Vocal cord palsy

7. Evaluation Clinical Single nodule Age<20 and >70, males Hard or fixed Unilateral/bilateral nodules Nodes IDL for cord palsy

8. Evaluation USG neck Solid or cystic Hypoechoic lesions Irregular lesions Microcalcifications Vascularity on doppler Pick up asymptomatic nodules

9. Evaluation Thyroid profile Serum Thyroglobulin Serum Calcitonin Thyroid scan Hot/warm/cold nodule 20% malignant Serum Ca++

10. Evaluation CT Scan Not commonly needed Better when suspecting mediastinal disease PET Scan FNAC Accurate for PTC and MTC Cannot diagnose FTC

11. Treatment Total Thyroidectomy with Central Neck Dissection RAI scan and sos Ablation Suppressive dose of thyroxine

12. Surgery Total thyroidectomy Lower LRR Can use RAI for residual disease Serum Tg a useful post op monitoring marker Approx 2% risk to RLN and parathyroids Hemithyroidectomy No difference in OS Avoids risk of hypoparathyroidsm No need for replacement therapy and risks associated

13. Risk stratification Risk Grading AGES, AMES, MACIS, TNM Histology Tall cell, Columnar, Hurthle cell Metastasis Tumour grade LVSI especially for FTC

14. Nodal disease No effect on OS Increased risk of LRR Ipsilateral nodal disease 40% with PTC 10% with FTC 25% with Hurthle cell ca

15. Surgery for Nodes Central neck dissection Ipsilateral/bilateral for all Selective neck dissection For minimal disease (ipsilateral) Comprehensive neck dissection For gross disease in nodes Include superior mediastinal nodes

16. Radioiodine treatment All patients who have undergone TT/ significant residue Targeted therapy Ablates tumour and adjacent tissue Dose 75-150mCi, max dose 1500mCi Not indicated in Micropapillary ca, <15mm lesion in young females Lobectomy as treatment Complications: Xerostomia, menopause, azzospermia, flare phenomenon, BM suppression, AML

17. Post treatment TSH suppression 0.1micro IU/ml in high risk disease Thyroxine in doses 150-200mcg per day No proven benefit of OS or reduction of LRR Risks of osteoporosis, AF, cardiac risk in elderly needs management

18. Role of EBRT Indications Non iodine avid disease Mediastinal bulky nodes Bone metastasis Brain metastasis Locally inoperable massive disease SVCO

19. Newer therapies Targetted therapy Aimed at BRAF Kinase and MAPK pathway COX 2 inhibitors Antiangiogenic therapy Anti EGFR therapy

20. Follow Up Review adequacy of replacement T3/T4 USG neck, CXR for recurrence RAI scans 6 monthly till 2 scans are normal Serum Tg levels in TT patients (<2ng/ml when anti Tg levels are not elevated) Imaging as directed by findings

21. Prognosis DTC 85% of patients with DTC :disease-free after initial treatment 10–15% : recurrent disease 5%: distant metastases Distant metastases :lungs (50%), bones (25%), lungs and bones (20%) ,10-year-survival rates ranging from 25% to 42% Overall 20yr survival 95%

23. 5th-6th decades

24. Rapidly expanding mass (> 5cm in 80%)

25. Short history and multiple local symptoms

26. ETE, LN 2’, VC palsy in 50% at Δ

27. Mets common (LN, lung)

28. Management controversial – almost 0% OS

29. Rarely resectable

31. MEDULLARY CARCINOMA Prognostic Features T size High Preopcalcitonin s/o high tumour load Advanced age Extrathyroid extension LN in mediastinum Perinodal invasion Incomplete excision Histopathologic features Type of syndrome in hereditary MTC

32. MEDULLARY CARCINOMA TT Central compartment LND Ipsilateral LND /biateral neck and mediastinal dissection RT to neck and mediastinum when there is a high nodal load

33. Medullary Cancer Follow up Imaging Calcitonin and CEA levels Asymptomatic hypercalcitoninemeia with no apparent disease on imaging needs to be followed up

34. Questions