Papillary Carcinoma Thyroid and management.pptx

Discussion on papillary thyroid carcinoma

1. Papillary Thyroid Carcinoma dR Tabeer arif

2. Lay Out Introduction Epidemiology Etiology Pathophysiology Relevant Anatomy Clinical presentation Investigations Staging Prognostic factors Treatment modalities Recurrent disease Outcome

3. Introduction Differentiated thyroid cancer (DTC) consists of a group of malignant tumours derived from the thyroid follicular cell Include: Papillary thyroid carcinoma (PTC) Follicular thyroid carcinoma

4. Epidemiology 75-80% of all thyroid malignancies Most common paediatric Thyroid malignancy 20-50 years of age Female predominance

5. Aetiology Radiation exposure Familial factors Iodine deficiency/ adequecy

6. Anatomy Arterial supply: Superior thyroid artery, inferior thyroid artery, thyroid Ima artery Venous drainage Superior thyroid vein, middle thyroid vein, inferior thyroid veins Lymphatic drainage Level II,III, IV,VI

7. Pathophysiology Colloid filled follicles with papillary projections Orphan Annie eye nuclei Psammoma bodies 3 growth patterns: Pure papillary Follicular Mixed

8. Lymphatic spread Multifocal ( upto 80%) Histological variants: Tall cell variant Papillary Microcarcinoma (less than 10mm) Monoclonal origin (RAS, RET/PTC, BRAF, TRK)

9. Clinical Presentation Solitary nodule Age Gender Increase in size Dysphagia Dyspnoea Change in voice Radiation exposure Family history Cervical mass

10. Swelling in front of neck that moves with deglutition Consistency (firm) Fixation Cervical lymphadenopathy Vocal cord paralysis

11. Investigations Thyroid function tests Serum calcium levels Thyroid antibody levels Ultrasound neck FNAC Scintigraphy

12. Staging T Tx Primary tumour can not be assessed T0 No evidence of primary tumour T1a Tumour size <1cm limited to thyroid T1b Tumour size 1-2cm limited to thyroid T2 Tumour 2-4cm limited to thyroid T3 Tumour >4cm limited to thyroid, minimal extension to perithyroid soft tissue, sternocleidomastoid muscle T4a Any size extending beyond thyroid capsule, invades subcutaneous soft tissue, larynx, trachea, oesophagous, Recurrent Laryngeal Nerve T4b Tumour invades prevertebral fascia, mediastinal vessels, encases carotid artery

13. N N0 No regional lymph node metastasis N1a Level VI ( pretracheal , paratracheal including prelaryngeal and Delphian) lymph node metastasis N1b Metastasis in other unilateral, bilateral or contralateral Cervical or upper Mediastinal Lymph Nodes

14. Prognostic Factors Age Gender Histology (tall cell, columnar cell variants) Extent Extra thyroidal invasion Lymph node metastasis Distant metastasis

15. TNM Staging stage 10 year mortality (%) I <45 years >45 years Any T, any N, M0 T1, N0, M0 1.7 II <45 years >45 years Any T, any N, M1 T2, N0,M0 and T3,N0,M0 15.8 III >45 years T4,N0,M0 and any T, N1,M0 30 IV >45 years Any T, any N, M1 60.9

16. AGES Age, grade, extra thyroidal invasion, size AMES Age, metastasis, extrathyroidal invasion, size GAMES Gender. Age, metastasis, extra thyroidal invasion, size DAMES DNA ploidy +AMES

17. Treatment Surgical Non surgical

18. Category Treatment Thy1 USG assessment +/- repeat FNAC Thy2 Correlation with clinical and radiological findings Thy3a Further assessment (USG + repeat FNAC) thy3 on repeat FNC warrants a MDT Thy3f Diagnostic Hemithyroidectomy Thy4 Diagnostic Hemithyroidectomy Thy5 Therapy according to Tumour Type

19. Lobectomy & thyroxine suppressive therapy: Tumour less than 1cm, N0 Total thyroidectomy : h/o radiation exposure in childhood Tumour >1cm Positive lymph node involvement Distant metastasis Extra thyroidal extension Familial disease

20. Diagnosis of PTC made after lobectomy: Completion thyroidectomy (within 8 weeks of histological diagnosis)

21. Cervical Lymph Nodes Nodal disease in level VI at surgery – Central Neck Dissection suspicious / clinically involved nodes in Lateral neck – Selective Neck Dissection level IIa – Vb (lateral neck dissection) High risk patients with clinically uninvolved nodes – total thyroidectomy + level VI neck dissection Internal Jugular Vein, Sternocleidomastoid muscle, skin involvement – excision along with lateral neck dissection

22. ExtraThyroid Extension Higher rates of recurrence and mortality Risk factors : Age>50 years , size>4cm , aggressive histological variant Strap muscles, RLN and Trachea

23. Management : Strap muscle, unilateral RLN – complete resection with minimal morbidity B/L RLN – incomplete resection, preservation of 1 or both RLN, post-op Radioactive Iodine, External Beam Radiation (EBR) Superficial invasion of laryngotracheal tree – shaving only (microscopic disease left behind) Gross invasion of larynx/trachea – radical resection OR External beam Radiation +/- radioactive Iodine EBR – in residual disease that fails to concentrate radioactive Iodine

24. In Pregnancy Higher chance of thyroid nodule presenting in pregnant women of being Malignant Elective surgery - 2 nd trimester or after delivery Airway compromise – early intervention Adjuvant radioiodine treatment until after breastfeeding is stopped No Impact on Prognosis of treatment delay after delivery

25. In Childhood More likely to malignant More advanced stage at presentation Higher lymph node recurrence (post op) Less fatal, better overall survival rates h/o radiation exposure Management : Total Thyroidectomy, selective neck dissection (in positive nodal disease) Radioactive Iodine treatment Lifelong regular serum thyroglobulin levels

26. Adjuvant Therapies Radioactive Iodine Decrease in distant metastasis External beam Radiotherapy High risk of locoregional recurrence Tumor failure to concentrate radioiodine Thyroxine suppression therapy TSH (lower limit of normal), T4 (normal)

27. Papillary Micrcarcinoma Thyroid Lobectomy – unifocal micro PTC, no other risk factor High risk patients, lymph node involvement, h/o radiation, multifocal disease, family history…. Total thyroidectomy

28. Follow Up Life long follow up Serial TSH Stimulated Thyroglobulin levels Ultrasound neck History Examination Serum Calcium Thyroid function tests

29. Disease free – Low risk patient after total thyroidectomy and Radioiodine ablation Complete resection No clinical evidence of tumour No uptake outside thyroid bed on post-op radioiodine scan Neck Ultrasound - ve Serum thyroglobulin antibodies – ve Thyroglobulin undetectable (>1microgram) during TSH suppression and stimulation

30. Post-op Risk Stratification Distant metastasis Residual Disease Histology Extra Thyroidal invasion Low, moderate and high risk

31. Recurrence Recurrence over long period 60% in first 10 years Elevated serum Thyroglobulin – neck ultrasound – FNAC – radioiodine scan – FDG PET More in thyroid bed and cervical lymph node basins Disease detected by scintigraphy – treated by Radioiodine ablation Surgical treatment – level VI clearance with skeletonization of RLN Selective lymphadenectomy – recurrent Nodal disease (previously dissected neck)

32. Selective Neck Dissection – nodal recurrence (preciously untreated or ‘berry picked’ neck for + ve nodes) Distant metastasis (lungs, bone, brain) – Radioiodine Extensive bony metastasis – External Beam Radiation +/- resection

33. Conclusion PTC has excellent prognosis Low rates of recurrence and mortality Risk stratification, appropriate resection plan and vigilant follow up

34. Thank You