Synchronous cribriform morular variant of papillary and follicular carcinoma thyroid: A case series of a rare collision tumor

Abstract

The synchronous presence of cribriform-morular variant of papillary thyroid carcinoma with follicular carcinoma is very rare. Collision tumors or the coexistence of histologically distinct malignant tumors in the same organ constitutes only 1.0% of all thyroid malignancies. The postulated hypothetical theories to the collision tumors are stem cell theory, collision theory, and hostage theory, which try to explain the synchronous association of these thyroid neoplasms. We report the case series of a synchronous cribriform-morular variant of papillary thyroid cancer and follicular thyroid carcinoma, which to our knowledge has not been reported till date.

Keywords

• carcinoma
• cribriform papillary
• follicular
• synchronous
• thyroid