THYROID NEOPLASMS OF PATHOLOGY ROBBINS.pptx

Thyroid malignancy

1. THYROID NEOPLASMS

2. 15-25 grams

3. “NODULES” Solitary vs. Multiple Younger vs. Older Male vs. Female Hx. neck radiation vs. NO Rx. “Cold” vs. HOT (really NOT-cold)

4. SOLITARY NODULES YOUNGER AGE MALES RADIATION HOT NODULES

5. ADENOMA THYROID Discrete,solitary,from thyroid epithelial cells DD:1. dominant nodule 2.follicular carcinoma nonfunctional.

6. pathogenesis Mutations of TSH receptor signelling pathway. Gain of function in TSHR or GNAS-Independent secretion of TSH-THYROID AUTONOMY-HOT NODULE RAS OR PIK3 CA

7. MORPHOLOGY solitary spherical encapsulated Compressing the adjacent thyroid Hge,necrosis,fibrosis and cystic changes

8. Well formed capsule Uniform follicles Uniform cell size Compression of adjacent thyroid

9. Clinical features Painless Difficulty in swalowing Non functioning-cold nodules USG ,FNAC

10. H Ü RTHLE CELL ADENOMA, note “atypia”

11. CARCINOMAS 4 MAJOR TYPES 1.PAPILLARY CA 2.FOLLICULAR CA 3.ANAPLASTIC CA 4.MEDULLARY CA

12. Papillary carcinoma 1.RET gene in chr 10-TK receptor expression-RET PTC fusion gene-transcriptional activation 2.BRAF MUTATION-Prognostic significance

13. ORPHAN ANNIE CELLS in PAPILLARY CARCINOMA

14. Follicular carcinoma Mutations that activates RAS OR PI3K AKT of TK receptor pathway Translocation of (2;3)(q13;p25)producing PAX8 PPARG FUSION GENE -thyroid development and terminal differentiation of cells

15. Anaplastic or undifferentiated carcinoma RAS ,PIK3CA MUTATION INACTIVATION OF TP53 or activation of beta catenin

16. Medullary carcinoma MEN 2 RET mutation

17. MEDULLARY CARCINOMA of the thyroid with “HYALINIZATION”, i.e., AMYLOID!!!

18. HYALINIZATION showing APPLE GREEN birefringence in CONGO RED stain, i.e., AMYLOID

19. Papillary Carcinoma Most common Morphology Branching papillae with central fibro vascular core Uniform cuboidal cells Nuclear Feature Dispersed Chromatin Clear or empty nucleus – Ground glass / Orphan annie eye nucleus Pseudoinclusion , intranuclear grooves psammoma bodies – concentric calcified structure

20. Variants Tall cell variant Diffuse sclerosing variant Papillary microcarcinoma Follicular variant Columnar cell variant Solid variant Cribriform morular variant Hobnail variant

21. Clinical Course Hoarseness Dysphagia Cough Dyspnea

22. Follicular Carcinoma 5 – 15 % Associated with Dietary iodine deficiency

23. Morphology Gross Similar to Follicular adenoma Microscopy Uniform follicles with colloid , capsular and vascular invasion present Benign Malignant Complete capsule Circumferential fibrosis Compression of adjacent thyroid No compression No Capsular or Vascular invasion Capsular or Vascular invasion seen

24. Clinical Features Cold Nodules Hematogenous Spread Total Thyroidectomy Serum thyroglobulin – To monitor tumor recurrence

25. Anaplastic (Undifferentiated ) Carcinoma < 5 % Aggressive Arising from well differentiated thyroid carcinoma

26. Morphology Highly anaplastic cells including 1)Large pleomorphic giant cells 2) Sarcomatpus spindle cells 3) Mixed spindle and giant cells Positive for cytokeratin

27. Clinical Features Rapidly enlarging neck mass No surgical treatement

28. Medullary Carcinoma Neuroendocrine neoplasm dervied from parafollicular cells or ‘C’ cells Secrete Calcitonin Sporadic or Associated with MEN 2A or MEN 2B Familial Medullary thyroid carcinoma

29. Gross – Solitary nodule Infiltrative Necrosis Hemorrhage Polygonal to spindle shaped cells forming nests, trabeculae and follicles Amyloid deposits C Cell hyperplasia

30. Clinical course Mass in neck Dysphagia Hoarseness Cushing syndrome Diarrhea Serum Calcitonin Elevated CEA - Biomarker