Metástasis de carcinoma renal de células claras en mucosa de labio inferior

Metastatic lesions in the oral cavity represent 1% of malignant tumors. Renal cell carcinoma (RCC) is the third most common cause of metastasis to the head and neck region. Mucocutaneous dissemination is very rare. We report a case of an ulcerative lesion of the mucous membrane of the lower lip which was clinically considered to be an inflammatory lesion or a possible primary tumour in an 83-year-old patient without any significant previous medical history. The histopathological examination showed sheets and clusters of clear cells with delicate vascular channels. Immunohistochemical techniques were positive for CK AE1-AE3, Vimentin and CD10 and negative for CK7 and CK20. Histopathological and immunohistochemical findings were associated with metastatic clear cell RCC. All clear cell primary tumors were included in the differential diagnosis.