E5146. Retroperitoneal Tumors/Masses
  1. Paula Marinhas; No Affiliation
  2. Jhisel Lazcano; No Affiliation
  3. Victor Larrañaga; No Affiliation
  4. Lina Robledo; No Affiliation
  5. German Espil; No Affiliation
  6. Shigeru Kozima; No Affiliation
Primary retroperitoneal tumors originate within the retroperitoneal space. These tumors come from tissues of the retroperitoneal space or from embryonic remains contained therein. Secondary retroperitoneal tumors originate in the retroperitoneal space, depending on the retroperitoneal organs. Of the primary retroperitoneal neoplasms, between 70% and 80% are malignant in nature. The classification of retroperitoneal tumors is given according to the origin of the tissue (lymphatic, nervous, vascular, supporting muscle, connective, and fibroareolar). Tumors formed from embryological remnants of the urogenital crest (Wolffian and Müllerian ducts and germinal cells) and from the primitive notochord are also included. Also considered primary retroperitoneal tumors are those derived from the neural crest, such as paragangliomas of the organ of Zuckerkandl. A series of representative cases of each type will be shown in this exhibit.

Educational Goals / Teaching Points
Presentation of cases of retroperitoneal tumors/masses. Recognize the tomographic features of retroperitoneal masses. Identify the organ of origin of a retroperitoneal tumor.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Retroperitoneal tumors/masses on CT.

Retroperitoneal masses can arise from various tissues and are a diverse group. MDCT imaging is valuable in assessing the characteristics of retroperitoneal tumors in relation to their size and proximity to abdominal organs and structures, as well as to the large retroperitoneal vessels.