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Small to medium left pleural effusion. Extensive retroperitoneal soft tissue mass extending from the left subdiaphragmatic space into the left pelvic sidewall. This mass has a more rounded, nodal appearance anteriorly as it extends into the mesentery. The mass elevates the aorta and involves and surrounds arterial and venous vasculature, resulting in narrowing of the left renal arteries and compression of the left renal vein.

There is mottled, heterogeneous appearance of multiple vertebral body levels in the pelvis, with areas of lucency and sclerosis. This can be best appreciated on the sagittal and coronal reformats.