Penile Metastasis from Renal Cell Carcinoma: Diagnosis and Posttreatment Response Seen on Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography.

We present fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) findings in an extremely rare case of penile metastasis from renal cell carcinoma. A 66-year-old male, a known case of renal cell carcinoma, underwent FDG PET-CT. The scan showed metabolically active cervical lymph nodes, lytic skeletal lesions, deposit in the left adrenal gland, and nodules in the bilateral lungs, indicating metastatic disease. In addition, a hypermetabolic lesion was seen in the corpus cavernosum of the shaft of the penis, suggestive of penile metastasis. Follow-up PET-CT after tyrosine kinase inhibitor therapy showed reduction in size and metabolic activity of all previously seen lesions including penile lesion, suggestive of favorable response to therapy.