Giant retroperitoneal liposarcoma incidentally discovered during bariatric surgery

Neoplasms occur more frequently in individuals with obesity and may go unnoticed during the workup for a bariatric procedure in part because there are no guidelines to screen patients for intra-abdominal malignancy before bariatric surgery, and because obesity can mask even very large abnormal masses on physical exam. Many reports in the literature describe a variety of masses being discovered incidentally during bariatric procedures. Liposarcomas are soft tissue neoplasms with striking potential to grow to gigantic proportions. These tumors often present as a disfiguring mass palpable to physician and patient alike. We present a case in which a giant mass measuring 41 cm and 10.2 kg was undetected in an individual with obesity and was incidentally found during bariatric surgery. To our knowledge this is the first case in the literature of a giant liposarcoma being initially discovered during a bariatric procedure. We discuss management considerations for the bariatric surgeon who incidentally discovers a giant retroperitoneal mass at the time of gastric bypass.