RESUMO
BACKGROUND: primary squamous cell carcinoma (scc) of the thyroid is a rare malignant tumor that needs to be distinguished from other neoplasms. Cases of papillary carcinoma merging in association with squamous cell carcinoma are extremely rare. AIM: the characteristics of such association will be studied herein through a review of literature. CASE REPORT: we report a case of an 87-year-old patient presented with an enlarged right lobe of the thyroid. Thyroid scintigraphy revealed a cold nodule. Clinically, malignancy was suspected. Histopathologic diagnosis was a well-differentiated scc associated with areas of papillary carcinoma. Exhaustive clinical, endoscopic and radiological examinations did not reveal any primary site of scc or any contiguous spread from neighboring structures. Surgery was followed by radiotherapy, but the patient died 6 months later. CONCLUSION: the coexistence of epidermoide and papillary carcinomas in the thyroid gland must be known because of its prognostic impact.