No improvement in overall survival with lymph node removal in treatment of advanced ovarian cancer

Removing the aortic and pelvic lymph nodes during surgery for advanced ovarian cancer improves progression-free survival but not overall survival, according to a new study in the April 20 issue of the Journal of the National Cancer Institute.

Ovarian cancer is the fifth most common cancer in women worldwide. In the United States, about 25,000 women were diagnosed with the disease in 2004 and 16,000 women died from it. Long-term survival is possible after surgery and chemotherapy, but only about 30% of patients with advanced ovarian cancer survive 5 or more years after diagnosis. Retrospective studies have suggested that lymphadenectomy–the removal of the aortic and pelvic lymph nodes during cytoreductive surgery to remove the cancer–may improve survival, but the value of the procedure remains controversial.

To determine whether systematic aortic and pelvic lymphadenectomy improves progression-free and overall survival, Pierluigi Benedetti Panici, M.D., of “La Sapienza” University in Rome, and colleagues conducted a clinical trial in which 427 patients with advanced ovarian cancer were randomly assigned to undergo either primary cytoreductive surgery followed by lymphadenectomy or cytoreductive surgery only. The patients were followed for an average of 68.4 months.

The 5-year progression-free survival rate was greater among patients treated with lymphadenectomy (31.2%) than among those who had only enlarged nodes removed (21.6%), and the duration of progression-free survival was also longer in the lymphadenectomy group (29.4 months versus 22.4 months). However, the 5-year overall survival rate and the median overall survival duration were similar in both groups. In addition, compared with the group that did not have lymphadenectomy, women who were treated with lymphadenectomy had a longer operating time, and more of these women required blood transfusions.

“This study found that 1) the addition of systematic lymphadenectomy to cytoreductive surgery prolonged progression-free survival, which, in turn, may have an important impact on the quality of life of patients with advanced ovarian cancer; [and] 2) systematic lymphadenectomy did not prolong overall survival, probably because effective platinum-based first- and second-line … chemotherapies might have diluted the impact of systematic lymphadenectomy on the risk of death,” the authors write.

In an editorial, Setsuko K. Chambers, M.D., of the Arizona Cancer Center in Tucson, describes the strengths and weaknesses of this prospective study of lymphadenectomy for advanced ovarian cancer. “This pivotal trial should be considered definitive, and the findings used to dictate clinical management,” she writes. “As disappointing as the result may be to some gynecologic oncologists, the body of evidence does not favor including systematic lymphadenectomy as part of front-line maximal surgical debulking in the management of advanced ovarian cancer.”