In the Basis of Hashimoto’s Thyroiditis, to Form Papillary Thyroid Carcinoma, Metastasized and Then to De-Differentiate into Poorly Differentiated Squamous Cell Carcinoma

Thyroid squamous cell carcinoma is very rare. At present, it limited to case reports. Since the thyroid follicular epithelium non-squamous epithelium, how primary (SCC) of occurs still a controversial issue. Hashimoto’s thyroiditis (HT) considered be an independent risk factor for cancer, under basis HT, tumor cells evolve and develop papillary (PTC), particularly de-differentiate into SCC elusive. We report 72-year-old female patient who developed multiple subtypes PTC on finally within local foci lymph node metastasis. found that there was variety sub-types in this background HT. Pathomorphology, immunohistochemistry, molecular pathology have confirmed derived from PTC, then poorly differentiated and/or anaplastic carcinoma. also conducted comprehensive literature review.