Metastatic Renal Cell Carcinoma Presenting as Painful Chewing Successfully Treated with Combined Nivolumab and Sunitinib.

Metastatic renal cell carcinoma (RCC) to the head and neck is rare. It is the third-most common cause of distant metastasis to the head and neck, after breast cancer and lung cancer. Several drugs are available to treat metastatic RCC including high-dose interleukin and targeted therapy. Immunotherapy with nivolumab was recently approved by the US Food and Drug Administration (FDA) as a second-line treatment for patients with metastatic RCC.

We present a case of metastatic RCC in a 71-year-old man with a single complaint of a 1-year history of pain while chewing food. Positron emission tomography-computed tomography showed diffuse metastatic disease. Nivolumab, off-label use before its recent FDA approval, was combined with sunitinib and resulted in an excellent and ongoing response.

RCC is the third-most common cause of distant metastasis to the head and neck. The patient described in this case did not have any symptoms commonly seen in RCC, such as painless hematuria, weight loss, anorexia, fatigue, or anemia, despite the bulk of his disease. The other important aspect of this case is the almost complete response of his metastatic disease to the combination of nivolumab and sunitinib that was used off label before the FDA issued the approval. Future clinical trials should look at combining immunotherapy with targeted therapy in metastatic RCC.