Retroperitoneal Biopsy: Indications and Imaging Approach

Abstract

The contents of the retroperitoneum are defined by the boundaries of the potential space behind the posterior abdominal parietal peritoneum and the fascia investing the lumbar musculature. Primary retroperitoneal neoplasms are a rare group of tumors which do not arise from a specific organ but rather originate from tissues or rests of embryonic cells which exist in the retroperitoneum (Rodríguez et al., Arch Esp Urol, 63[1], 13–22, 2010). The most common variety is sarcoma, which accounts for up to 90 % of lesions after lymphoma is excluded. Liposarcomas and leiomyosarcomas are the next most common types, accounting for up to 15 % of tumors. The average age of presentation is during the fifth to seventh decades, and the tumors are often large in size at diagnosis due to the paucity of symptoms associated with growth of retroperitoneal tumors in general. Excluding lymphomas, the most frequent primary retroperitoneal malignancies in decreasing order include liposarcoma, MFH, leiomyosarcoma, rhabdomyosarcoma, and malignant nerve sheath tumors (Nishino et al., Radiographics, 23[1], 45–57, 2003). Both Hodgkin’s and non-Hodgkin’s lymphoma may also occur in the retroperitoneum. Epithelial tumors may rise from the kidney, adrenal gland, and pancreas, and metastatic disease from germ cell tumors, primary carcinomas, or melanomas can also occur. Benign tumors may have neurogenic origins as well (schwannomas, neurofibroma, paraganglioma).