Study Overturns Previous Thinking on Lymphadenectomy in Patients With Ovarian Cancer

For many years, patients with advanced ovarian cancer underwent systematic pelvic and paraaortic lymphadenectomy. Despite debate over the necessity of the procedure, some studies reported that lymphadenectomy was associated with improved survival. However, according to the international, multicenter LION (lymphadenectomy in ovarian neoplasms) study published in The New England Journal of Medicine, this approach is not associated with longer overall survival (OS; primary endpoint) or progression-free survival (PFS) compared with patients who do not undergo lymphadenectomy.

The researchers assessed 647 patients with newly diagnosed advanced ovarian cancer (International Federation of Gynecology and Obstetrics stage IIB-IV) who had undergone macroscopically complete resection and had normal lymph nodes both before and during surgery. Patients were intraoperatively randomized between December 2008 to January 2012 to either undergo (n=323) or not undergo (n=324) lymphadenectomy.

Survival not improved with lymphadenectomy

Among patients who underwent lymphadenectomy, the median number of nodes removed was 57 (35 pelvic and 22 paraaortic nodes). There was no improvement in survival among patients who underwent lymphadenectomy: The median OS was 69.2 months in those who did not undergo the procedure versus 65.5 months in those who did (hazard ratio [HR] for death in the lymphadenectomy group = 1.06; 95% CI, 0.83-1.34; P=0.65). The median PFS was 25.5 months in both groups (HR for progression or death in the lymphadenectomy group = 1.11; 95% CI, 0.92-1.34; P=0.29).

Postoperative complications mount in lymphadenectomy group

Patients in the lymphadenectomy group reported more serious postoperative complications, including incidence of repeat laparotomy (12.4% vs 6.5%; P=0.01) and mortality within 60 days after surgery (3.1% vs 0.9%; P=0.049). The most common reason for repeat laparotomy was bowel leak or fistula.

“Patients with advanced ovarian cancer … did not benefit from systematic lymphadenectomy,” the researchers concluded.