An unusual mucin-secreting neoplasm presenting as a metastasis in the neck. Cytology

摘要

Dear Editor, Medullary carcinoma of the thyroid (MCT) is a malignant neoplasm arising from the parafollicular C cells.1 The classical MCT is characterized by the presence of solid nests of cells composed of polygonal, spindle or round cells separated by a fibrous stroma and containing variable amounts of amyloid.2 However, MCT may show various architectural patterns including papillary, follicular, glandular and carcinoid-like growth patterns.3"6 It can also show a variety of cell types including clear, small, oncocytic, squamous and giant cells.7"10 MCTs produce various peptide hormones and they are also known to produce melanin11'12 and mucin.13"16 Both extracellular and intracellular mucin have been demonstrated, and one study showed the presence of intracytoplasmic mucin in 50% of these neoplasms.