A retroperitoneal mass is an abnormal growth in the deep abdominal space behind the main abdominal lining.
Some people have no symptoms at first. Others may notice abdominal or back pain, swelling, weight loss, poor appetite, urinary problems, or pressure symptoms depending on the size and location.
Imaging helps show the size of the mass, which organs or vessels are close to it, and whether it looks cystic, solid, inflammatory, or suspicious for cancer.
CT and MRI help show which organs are involved and whether biopsy planning or surgical mapping is needed.
Management depends on what the mass is suspected to be and may include biopsy, surgery, oncology review, or monitoring.
This entry explains the finding. The next step is having a radiologist interpret your specific scan, not a general definition.
