We found no conclusive evidence to determine whether IDS between cycles of chemotherapy would improve or decrease the survival rates of women with advanced ovarian cancer, compared with conventional treatment of primary surgery followed by adjuvant chemotherapy. IDS appeared to yield benefit only in women whose primary surgery was not performed by gynaecologic oncologists or was less extensive. Data on QoL and adverse events were inconclusive.
The effect of debulking surgery after induction chemotherapy on the prognosis in advanced epithelial ovarian cancer. Gynecological Cancer Cooperative Group of the European Organization for Research and Treatment of Cancer.
Although the value of primary cytoreductive surgery for epithelial ovarian cancer is beyond doubt, the value of debulking surgery after induction chemotherapy has not yet been defined. In this randomized study we investigated the effect on survival of debulking surgery.
                Eligible patients had residual lesions measuring more than 1 cm in diameter after primary surgery. After three cycles of cyclophosphamide and cisplatin, these patients were randomly assigned to undergo either debulking surgery or no surgery, followed by further cycles of cyclophosphamide and cisplatin. The study end points were progression-free and overall survival. At surgery 65 percent of the patients had lesions measuring more than 1 cm. In 45 percent of this group, the lesions were reduced surgically to less than 1 cm.
                Of the 319 patients who underwent randomization, 278 could be evaluated (140 patients who underwent surgery and 138 patients who did not). Progression-free and overall survival were both significantly longer in the group that underwent surgery (P = 0.01). The difference in median survival was six months. The survival rate at two years was 56 percent for the group that underwent surgery and 46 percent for the group that did not. In the multivariate analysis, debulking surgery was an independent prognostic factor (P = 0.012). Overall, after adjustment for all other prognostic factors, surgery reduced the risk of death by 33 percent (95 percent confidence interval, 10 to 50 percent; P = 0.008). Surgery was not associated with death or severe morbidity.
                Debulking surgery significantly lengthened progression-free and overall survival. The risk of death was reduced by one third, after adjustment for a variety of prognostic factors.