What is the differential for this retroperitoneal mass?
Most likely represent nodal enlargement. Possibilities in thus young patient include lymphoma and testicular neoplasms.
Look carefully at the inferior most aspect of the CT. Did you see an abnormality?
A partially imaged left scrotal mass is noted.
CT of the abdomen and pelvis demonstrates a large para-aortic mass which in places encases the aorta. It is well circumscribed and has a few small vessels passing through it. The mass results in left-sided ureteric obstruction and hydronephrosis.
An abnormality in the left hemiscrotum can be seen on the most caudal aspect of both axial and coronal reconstructions.