Medullary thyroid carcinoma - Rare cytologic findings

OBJECTIVE: To describe some rare cytologic findings in medullary thyroid ca rcinoma. STUDY DESIGN: Review of the fine needle aspiration smears from 15 cases of medullary thyroid carcinoma that mere confirmed on histologic sections. The ages ranged between 31 and 67 years, 10 were female and 5 male. Thirteen w ere sporadic forms, and two were familial forms. RESULTS: Eight cases were classified as pleomorphic cell type and seven as monomorphic cell type. The smears revealed round, oval, triangular, polygon al and spindle-shaped cells, intracytoplasmic red granules, occasional intr anuclear inclusions, amyloid, binucleated and multinucleated cells, and thi ck, granular chromatin. CONCLUSION: The rare cytologic findings in this study were grape cells, cyt oplasmic nippling, elongated cytoplasmic processes, carrot-shaped nuclei, n uclear buddings, mast cell-like cells and a Burkitt's lymphoma-like appeara nce. These findings were rarely reported before.