Large Retroperitoneal Liposarcoma Diagnosed upon Radiological Evaluation of Mild Right-Sided Inguinal Hernia

While inguinal hernia is common in the primary care office, the differential diagnosis is extensive and includes infectious, inflammatory and neoplastic processes. Varicocele is another frequent, generally benign condition which occasionally reflects serious disease entities. Left-sided or bilateral varicoceles account for the overwhelming majority of varicoceles because the left gonadal vein drains into the left renal vein in contrast to the right gonadal vein, which drains directly into the inferior vena cava, thus making left-sided or bilateral venous congestion more likely. Presence of an uncommon unilateral right-sided varicocele thus warrants further radiological workup, in particular CT abdomen and pelvis, to evaluate for retroperitoneal pathology. We describe a case in which appropriate use of a variety of imaging modalities including testicular ultrasound and CT led to an important diagnosis of a large, well-differentiated liposarcoma in the right retroperitoneum of a patient with a right-sided groin mass. 1. Introduction Depending on the source, liposarcoma is described as either the most common or second most common type of soft tissue sarcoma (STS) in adults comprising 24% of extremity STS and 45% of retroperitoneal STS [1, 2]. There is male predominance of cases ranging from a slight increase in incidence to a twofold incidence in men [3–5]. Additionally, incidence of liposarcoma increases with age with most cases presenting between 50 and 60 years of age. The etiology in most cases is unclear, and liposarcoma is not generally believed to arise from benign lipomatous tumors. However, an increasing number of studies are elucidating cytogenetic abnormalities associated with the different subtypes of liposarcomas [5, 6]. Liposarcomas can develop in any location in the body. The most common sites are the thigh and retroperitoneum. In the extremity, the tumor may present as a soft, painless mass which enlarges at any number of speeds ranging from slowly across years to rapidly across months. Retroperitoneal liposarcoma most often presents as an asymptomatic abdominal mass, though infrequently patients will present with symptoms caused by the effect of the growing mass on adjacent structures (incomplete obstruction, gastrointestinal bleeding, and pain) [5]. The World Health Organization categorizes liposarcoma into five distinct histologic subtypes: well differentiated, dedifferentiated, myxoid, pleomorphic, and mixed-type. CT and MR imaging findings may provide clues about the particular histology of a lesion suggestive of liposarcoma [1, 5, 7,