Squamous Cell Carcinoma of the Thyroid as a Result of AnaplasticTransformation from BRAF-Positive Papillary Thyroid Cancer

Papillary thyroid carcinoma (PTC) is the most common malignant neoplasm of the thyroid. Majority of the PTC carries anexcellent prognosis. However, patients with tall cell variant (TCV) of papillary thyroid carcinoma have a worse prognosis thanthose with the classic variant. On the other hand, squamous cell carcinoma of the thyroid (SCT) is an unusual neoplasm thought toarise as a primary tumor or as a component of an anaplastic or undifferentiated carcinoma. We report a patient with TCV of PTCpresenting years later with squamous transformation. In addition, the patient was found to have BRAF mutation. Such de-differentiation is considered to be a rare phenomenon and has been reported only in the form of case reports in the literature. (erelationship between BRAFV600E mutation and squamous cell transformation of papillary thyroid cancer is unknown at thistime. Meticulous pathology is needed to identify such variants. Our patient responded to treatment with concurrent chemo-therapy with carboplatin and paclitaxel along with radiation.