An Unusual Mixed Thyroid Carcinoma: A Surgical and Pathological Rarity.

The incidence of mixed thyroid carcinoma of poorly differentiated thyroid carcinoma (PDTC) and papillary carcinoma thyroid is very unusual. PDTC exhibits a high degree of dedifferentiation and histopathological confirmation is done based on Turin's criteria. This type of carcinoma has a poor prognosis and the survival rates at five and ten years post-diagnosis are significantly lower compared to well-differentiated thyroid carcinomas. Surgery is the best mode of treatment at present. This is a case of a 71-year-old female who underwent total thyroidectomy with modified radical neck dissection which yielded a histopathological variant comprising PDTC and papillary thyroid carcinoma. The patient was followed up with a serial thyroglobulin antibody test and ultrasound of the neck at six months and one year, and both were found to be normal.