Retroperitoneal Lymph Node Dissection: Anatomical and Technical Considerations from a Cadaveric Study

Abstract

Metastatic testis cancer in the retroperitoneum presents a technical challenge to urologists in the primary and post-chemotherapy settings. Where possible, bilateral nerve sparing retroperitoneal lymph node dissection should be performed in an effort to preserve ejaculatory function. However, this is often difficult to achieve, given the complex neurovascular anatomy. We performed what is to our knowledge the first comprehensive examination of the anatomical relationships between the sympathetic nerves of the aortic plexus and the lumbar vessels to facilitate navigation and nerve sparing during bilateral retroperitoneal lymph node dissection. The relative anatomy of the infrarenal vasculature (lumbar vessels, right gonadal vein and inferior mesenteric artery) was investigated in 21 embalmed human cadavers. The complex relationships between these vessels and the sympathetic nerves of the aortic plexus were examined by dissection of an additional 8 fresh human cadavers. Analysis of the infrarenal vasculature from 21 cadavers demonstrated that the position of the right gonadal vein and the inferior mesenteric artery may be useful to locate the right superior lumbar vein and the first pair of infrarenal lumbar arteries as well as the common lumbar trunk (vein) and the second pair of infrarenal lumbar arteries, respectively. Furthermore, the lumbar splanchnic nerves supplying the aortic plexus were most often positioned anteromedial to the respective lumbar vein. The current study describes the complex neurovascular relationships that are crucial to performing successful nerve sparing retroperitoneal lymph node dissection. Surgical techniques are also discussed. Collectively, these results may help surgeons decrease the rate of postoperative retrograde ejaculation and/or anejaculation.