Unusual Presentation of Differentiated Thyroid Collision Tumor

Collision tumors are rare clinical entities where two histologically and morphologically distinct tumors within the same organ with no histological admixture of different tumor cells. Some of the organs implicated are the stomach, liver, adrenal gland, lungs, ovary, kidneys, and colon. The thyroid gland, collision tumors are rare existent about 1% of all thyroid malignancies with co-occurring between medullary thyroid carcinoma and papillary thyroid carcinoma [1].