A 36-year-old woman with a 2-week history of fever and markedly elevated lactate dehydrogenase levels. Nonenhanced CT and contrast-enhanced CT showed hepatosplenomegaly, diffusely decreased attenuation of the liver, and homogeneous enhancement in the hepatic and splenic parenchyma. 18F-FDG PET/CT revealed diffuse intense heterogeneous uptake by the liver (like superscan in bone scintigraphy). A liver needle biopsy confirmed the diagnosis of hepatosplenic alphabeta T-cell lymphoma. Subsequently, she received chemotherapy. The follow-up 18F-FDG PET/CT showed decreased 18F-FDG uptake in the liver and spleen.