Pulmonary carcinosarcoma: 18F-FDG PET/CT imaging.

We present a case of pulmonary carcinosarcoma. The patient is a 31-year-old man with a history of infectious mononucleosis in whom a right lung mass was found. His age is lower than the mean age at which pulmonary carcinosarcoma is usually reported. Chest CT scan showed a lobulated 29-mm mass in the right upper lung and multiple hypervascular liver nodules. FDG PET/CT showed increased FDG uptake in the right upper lung nodule (SUVmax, 4.1). However, the hepatic radiouptake showed only background activity. The liver nodules were stable at the 1-year follow-up period and were suggestive of hemangiomas.