Richter transformation with marked plasmacytic differentiation, mimicking plasma cell neoplasm

[摘要] The patient is a 75-year-old man with a history of chronic lymphocytic leukemia (CLL), status post three courses of chemotherapy, andreached complete remission (CR). He presented with a right elbowmass. PET-CT showed FDG-avid nodular lesion in the soft tissue, most notably in the right upper elbow and left gluteal region, and also inthe left lower lobe of the lung. The largest nodule in the right elbowmeasured 5.5 × 4.5 cm, which was biopsied.