A case of a large, painless retroperitoneal mass causing hydronephrosis and biliary obstruction.

A 56-year-old man presented with abdominal distention over a few months. He was otherwise well and routine blood tests were normal. Examination of the abdomen revealed a firm swelling. CT scan was performed for further evaluation.A large, cystic, non-enhancing mass on the right side of the abdomen was observed on CT scan. This was closely related to the right psoas muscle with secondary compression of the right ureter and resultant right-sided hydronephrosis (figure 1).Figure 1 Coronal reformat demonstrating the mass …