Natural killer cell activity and progression-free survival in ovarian cancer

A longitudinal evaluation of the natural killer (NK) cell activity of peripheral blood lymphocytes was performed in 17 patients with advanced ovarian cancer (treated surgically and with subsequent multiagent chemotherapy) for a median follow-up period of 32 months. At the time of primary treatment, the mean value of NK cell activity was significantly lower in patients who then had disease progression (p < 0.05) than in patients with progression-free survival. During the follow-up period, no significant modifications of the NK cell activity were observed; only at the time of clinical disease progression did the NK cell activity show a significant reduction. We conclude that the NK cell activity is a potentially important prognostic factor.