Three Synchronous Atypical Metastases of Clear Cell Renal Carcinoma to the Maxillary Gingiva, Scalp and the Distal Phalanx of the Fifth Digit: A Case Report

Oral cavity metastasis of malignant tumors is extremely rare and accounts for only 1% of all malignant oral tumors. Renal cell carcinoma (RCC) can metastasize to any part of the body, with a 15% risk of metastasis to the head and neck region when the disease is disseminated and a 1% risk when it is not. RCC also is the third most common infraclavicular neoplasm that metastasizes to the oral cavity, after lung carcinoma in men and breast carcinoma in women. In the maxillofacial region, the nasal cavity and paranasal sinuses are the most commonly affected sites, followed by the oral cavity. This report describes the case of a 51-year-old man with a history of clear RCC presenting with 3 synchronous atypical metastases of this tumor to the maxillary gingiva, scalp, and distal phalanx of the fifth digit. Clinical findings, diagnosis, pathology, and treatment of these lesions are discussed. Metastasis of RCC should always be included in the differential diagnosis when a new oral and maxillofacial lesion appears in a patient with a history of RCC because the metastatic lesions can often present in a broad spectrum of forms. The rapid growth of these lesions should alert clinicians to avoid any delays in biopsy examination and subsequent treatment, which is usually palliative, because prognosis is usually poor.