Rationale and definition of the lateral extension of the inguinal lymphadenectomy for vulvar cancer derived from an embryological and anatomical study.

BACKGROUND AND OBJECTIVES: The objective of the present study was to define the location of the most lateral superficial inguinal node lying along the inguinal ligament, through an embryological and anatomotopographical study, in order to rationalize the lateral extension of the groin lymphadenectomy in vulvar cancer. METHODS: Sections of the upper portion of the femoral triangle belonging to three human fetuses, whose crown-rump (CR) length ranged from 70 to 310 mm, corresponding to a developmental age of 11 and 35 weeks, were studied. In addition, for an objective topographical evaluation of the disposition of the superficial inguinal lymph nodes, adult cadavers photographs of dissected Scarpa's triangle, reported in anatomical atlases, were analyzed. RESULTS: Both the embryological investigation and the anatomotopographical evaluation on cadavers photographs demonstrate that the most lateral superficial inguinal lymph node does not rise above the medial margin of the sartorius muscle, nor far lateral to the point where the superficial circumflex iliac vessels cross the inguinal ligament. CONCLUSIONS: On the basis of the present study, the authors believe that the superficial circumflex iliac vessels could represent the lateral surgical landmark, easily detectable, at which the inguinal lymphadenectomy should cease. Therefore, there is no need to extend the lateral excision to the anterior superior iliac spine. Finally, leaving the fatty tissue laterally to these vessels, some lymphatic channels could be preserved, decreasing the incidence and the entity of wound seroma and lymphedema.