[A Resected Case of Castleman's Disease That Was Difficult to Diagnose Preoperatively].

A 70-year-old man was referred to our hospital and admitted after abdominal computed tomography(CT)examination revealed a tumor in the retroperitoneum. The specific blood test findings were poor, and surveillance CT demonstrated a wellcircumscribed, enhanced mass measuring 40mm with calcification behind the horizontal portion of the duodenum. The tumor presented with a slightly high signal in low signal, T2 in T1, and it showed a diffusion decrease in DWI; the simple abdominal MRIrevealed heterogeneous accumulation of SUVmax 3.