Carcinoma de Células Escamosas de Tiroides: A Propósito de un Caso

primary squamous cell thyroid carcinoma (psctc) is a rare and aggressive tumor of uncertain origin. when squamous carcinoma is diagnosed, it is mandatory to exclude the possibility of primary tumor arising from an adjacent structure or representing metastases from a primary growth elsewhere. aggressive surgical resection is the treatment of choice. however, the prognosis is poor, with a median survival of less than a year. death is usually secondary to progression of local disease. we report a case of a patient presenting with a thyroid mass; biopsy was consistent with squamous cell carcinoma. on immunohistochemistry tumor cells were negative for ttf1, thyroglobulin and calcitonin. cancer cells were positive for p63 and citok5. extensive workup excluded the possibility of extrathyroid origin. the patient was treated with chemoradiotherapy; he died 9 months later due to local progression.