Columnar cell variant of papillary thyroid carcinoma: Report of a rare case with cytohistological findings and review of literature

Abstract

Columnar cell carcinoma variant is a rare aggressive variant of papillary thyroid carcinoma (PTC) with unique histological features. They represent only 0.15%–0.2% of all PTCs. It is difficult to diagnose them on fine-needle aspiration cytology as they lack the classic nuclear features of PTC. Histologically they can mimic metastatic carcinomas from colon, endometrium, and lung. However, characteristic histological features combined with immunohistochemistry (IHC) findings help in accurate diagnosis. We describe the cytological, histopathological, and IHC findings of a rare case of PTC-CCV in a 23-year-old female and review the pertinent literature. It is important to diagnose this variant of PTC accurately, as it has prognostic and therapeutic implications.

Keywords

• carcinoma
• columnar variant
• papillary
• thyroid