Several regimens of immunotherapy have recently proven successful for multiple cancers, due to increased survival and quality of life. Rarely, immunotherapy with anti-programmed cell death protein 1 and programmed death-ligand 1 antibodies across cancer may cause immune-related pulmonary toxicity, with a low overall incidence, being particularly low among patients with melanoma and highest among individuals with lung cancer. In this vein, pulmonary toxicity is staged at 4 degrees according to the severity of the clinic and radiological findings, and its management is based on suppression of immunotherapy and administration of glucocorticoids. We report a case of pulmonary toxicity related to melanoma immunotherapy observed by F-FDG PET/CT.