Isolated temporalis muscle metastasis of renal cell carcinoma

Isolated head and neck metastasis of renal cell carcinoma (RCC) is relatively rare and metastasis to the temple area is very rare. Here, we present the case of a 51-year-old man who was diagnosed with RCC 2 years earlier and had a contralateral metastatic temple area lesion. The patient who was diagnosed with renal cell cancer and underwent a nephrectomy 2 years ago was referred to the plastic surgery department for a temple mass on the contralateral side. In the operative field, the mass was located in the temporalis muscle with a red-to-purple protruding shape. Biopsy of the mass revealed a metastatic RCC lesion. Computed tomography imaging showed a lobulated, contoured enhancing lesion. Positron emission tomography/computed tomography imaging showed high-fluorodeoxyglucose uptake in the right temporalis muscle. The patient underwent wide excision of the metastatic RCC including the temporalis muscle at the plastic surgery department. Skeletal muscle metastasis of head and neck lesions is extremely rare in RCC. Isolated contralateral temporalis muscle metastasis in RCC has not been previously reported in the literature. If a patient has a history of malignant cancer, plastic surgeons should always consider metastatic lesions of head and neck tumors. Because of its high metastatic ability and poor prognosis, it is very important to keep this case in mind.