The spread of ovarian cancer.

Spreading intra-abdominally, ovarian cancer reaches the upper abdomen relatively quickly. Metastases result from the implantation of cells from the primary tumour or, perhaps, may arise de novo from the peritoneal epithelium. The tumour also spreads via the lymphatics directly to the pelvic nodes, directly to the para-aortic nodes, or directly to both. Pelvic nodes were positive in 57.9% of patients of all stages. The highest incidence, 70.4%, was found in Stage III. The percentage of positive para-aortic nodes was lower, namely 50.9% overall incidence and 67.6% in Stage III. Concerning the concomitant involvement of pelvic and para-aortic nodes, 40.4% of patients with positive pelvic nodes also had positive para-aortic nodes. Of patients with negative pelvic nodes, 36.8% also had negative para-aortic nodes. Of all patients, 12.3% had positive pelvic nodes and negative para-aortic nodes. Conversely, 10.5% of all patients had positive para-aortic nodes and negative pelvic nodes. There is a significant association between the involvement of the diaphragm and that of the pelvic and para-aortic nodes. Of those patients with tumour deposits on the diaphragm, 84.4% also had positive retroperitoneal nodes. Conversely, 55.9% of patients with positive nodes also had tumour deposits on the diaphragm. This means that ovarian cancer spreads almost simultaneously in two ways: intra-abdominally and retroperitoneally. Surgical treatment must address both modes.