We describe a 57-year-old male with prior history of an absent right kidney and kidney transplant who was found to have lung cancer. Integrated positron emission tomography (PET) and computerized tomography (CT) scan was done for staging and showed uptake in the right upper lung primary and right renal fossae region which was suggestive of metastatic disease. An excisional biopsy of the right renal fossae mass showed that it was a hypoplastic kidney simulating a metastatic focus on PET scan. The patient eventually underwent a left upper lobectomy with a final pathological stage of T2N0M0. Positive PET scan areas should be biopsied to confirm the presence of metastatic disease before excluding patients from surgical treatment.