Medullary Thyroid Carcinoma

OBJECTIVE To describe some rare cytologic findings in medullary thyroid carcinoma.

STUDY DESIGN Review of the fine needle aspiration smears from 15 cases of medullary thyroid carcinoma that were confirmed on histologic sections. The ages ranged between 31 and 67 years; 10 were female and 5 male. Thirteen were 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, polygonal and spindle-shaped cells, intracytoplasmic red granules, occasional intranuclear inclusions, amyloid, binucleated and multinucleated cells, and thick, granular chromatin.

CONCLUSION The rare cytologic findings in this study were grape cells, cytoplasmic nippling, elongated cytoplasmic processes, carrot-shaped nuclei, nuclear buddings, mast cell-like cells and a Burkitt's lymphoma-like appearance. These findings were rarely reported before.