A case of renal cell carcinoma with solitary maxillary gingival metastasis 15 years after a nephrectomy

Renal cell carcinoma (RCC) tends to have a high frequency of distant metastasis.It has been reported that distant metastasis after more than ten years is not uncommon, however metastasis in the oral and maxillofacial region is rare.We report a case of metastatic RCC to the maxillary gingiva in the 15th year after a nephrectomy.A 72-year-old man was referred to our hospital with the chief complaint of a mass in the left upper gingiva.He had undergone a right nephrectomy for renal cell carcinoma 15 years ago.We performed a partial maxillectomy and histopathological examination of the resected specimen lead to a diagnosis of spindle cell carcinoma.Immunohistochemical staining revealed that CD10 and PAX8, which are specifically positive in renal cell carcinoma, were positive, and p63 and p40, which are positive in squamous cell carcinoma, were negative.The final diagnosis was RCC metastasized to the upper gingiva.