Between January 1986 and June 1990, systematic para-aortic and pelvic lymphadenectomy was performed in 208 women with untreated ovarian, endometrial, and cervical cancers. This study aimed to evaluate the median number of nodes collected from each pelvic and para-aortic group and to verify a new detailed nomenclature for the various lymph node groups. The para-aortic nodes were distinguished as paracaval, precaval, and retrocaval, depending on their relationship with the vena cava. Para-aortic, pre-aortic, and retro-aortic nodes were located close to the aorta. The nodes situated between the vena cava and aorta were designated intercavo-aortic. A median of 26 (range 15-48) para-aortic nodes were collected during ovarian or endometrial cancer operations. The lymphatic system of the pelvis was divided into six groups, depending on the relationship with the pelvic blood vessels. The pelvic nodes were distinguished as common, internal and external iliac, presacral, obturator, and parametrial. In cases of cervical cancer, the median number of pelvic nodes collected was 38 (range 20-88). Such anatomical study of the lymphatic system shows that a higher number of nodes than expected can be found in the retroperitoneum.