We present a case with space-occupying lesion in cirrhotic liver, diagnosed as hepatocellular carcinoma on immunohistochemistry, who underwent F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and showed FDG-avid lesions in liver as well as in the prostate. These findings guided in establishing the diagnosis of prostate cancer, metastasizing to liver by performing additional immunohistochemical markers. PET/CT was also useful in identifying coexisting non-Hodgkin's lymphoma.