FDG PET/CT in Primary Mucosa-associated Lymphoid Tissue Lymphoma of the Bladder

Primary lymphoma of the bladder is very rare. We described MRI and FDG PET/CT findings in a case of primary mucosa-associated lymphoid tissue lymphoma of the bladder. On MRI, the tumor appeared as a submucosal or intramural mass arising from the dome of the bladder. The tumor had no necrosis and showed isointensity relative to normal bladder wall on T1-weighted and T2-weighted images, marked diffusion restriction on diffusion-weighted images, and slight to moderate enhancement on post-contrast T1-weighted images. On FDG PET/CT, the mass showed homogeneous intense activity with SUV max of 11.9 mimicking bladder cancer.