Renal Cell Carcinoma Metastasis to the Maxillary Bone Successfully Treated with Surgery After Vascular Embolization: a Case Report

Background: Metastasis of renal cell carcinoma to the oral cavity is rare. Renal cell carcinoma metastases are regarded as radioresistant tumors and surgery is recommended. However, since metastatic renal cell carcinoma has poor prognosis and is composed of abundant blood vessels, it is sometimes difficult for clinicians to choose surgical therapy. Here, we report a case of a patient with renal cell carcinoma metastasis to the maxillary bone, which was successfully controlled by surgical therapy after vascular embolization, and provide a detailed literature review regarding the treatments and outcomes of renal cell carcinoma metastasis to the oral cavity.

Case Presentation: An 89-year-old Japanese man presented with an 8 × 8-mm granulomatous tumor with palpable pulsation in the left upper gingiva, which had been clinically suspected as an arteriovenous malformation or neoplastic lesion with rich blood vessels. Our patient had undergone left nephrectomy for clear cell carcinoma 7 years prior. Pulmonary metastasis had appeared 3 years later. After intravascular embolization, our patient underwent tumor resection of the maxilla with little intraoperative blood loss. The tumor was diagnosed on histopathology as a metastasis of clear cell renal cell carcinoma to the maxillary bone. Seventeen months after surgery, he died because of pulmonary metastasis without evidence of recurrence in the oral cavity.

Conclusions: Our literature review reveals that oral metastatic lesions of renal cancer often exhibit rapid enlargement and cause severe symptoms, such as dysphagia and bleeding. Although oral metastasis of renal cell carcinoma has a poor prognosis due to the presence of concurrent disseminated metastases, surgical therapy may be recommended because of its high local control rate and ability to maintain quality of life. Preoperative vascular embolization is considered to be effective to reduce intraoperative hemorrhage, which leads to safe surgery.