Results from neoadjuvant chemotherapy followed by surgery compared to chemoradiation for stage Ib2-IIb cervical cancer, EORTC 55994.

Abstract

5503 Background: Conflicting evidence on the value of neoadjuvant chemotherapy followed by surgery compared to concomitant chemoradiation in Stage IB2-IIB cervical carcinoma led to this multinational multicenter trial. As the trial is approaching completion of its follow-up, preliminary results are presented. Methods: Between May 2002 and June 2014 a total of 620 patients with FIGO stage Ib2-IIb were randomized between neoadjuvant chemotherapy followed by surgery (NACTS, arm 1, N=311) with standard concomitant chemoradiotherapy (CCRT, arm 2, N=309) . In arm 1, radical hysterectomy was required within 6 weeks after completion of cisplatin-based chemotherapy with a cumulative minimum of 225mg/m2, in arm 2, radiation consisted of 45-50 Gy plus boost concurrent with weekly cisplatin chemotherapy (40 mg/m2 per week). Primary endpoint was 5-yrs overall survival (OS). Results: Median follow-up time was 8.2 years ( 95% CI = 7.8 yrs – 8.6 yrs)) and similar between both arms. A total of 191 deaths (31%) occurred. Age, stage and histological cell type were balanced in both arms. Protocol treatment was completed in 459 (74%) patients (71% for NACTS; 82% for CCRT). In arm 1 238 (76%) patients underwent surgery. Main reasons for not having surgery as per protocol, were toxicity (25/74, 34%), progressive disease (18/74, 24%) and insufficient response to NACT (12/74, 16%). Additional radiotherapy was given to 113 patients (36.3%) in arm 1; additional surgery performed in 9 patients (2.9%) in arm 2. Short term severe adverse events (≥G3) occurred more frequently in arm 1 than in arm 2 (35% vs 21%, p < 0.001). The 5 year OS was 72% in arm 1 and 76% in arm 2 (not statistically significant, difference = 4.0% (95%CI: -4% - 12%); HR 0.87, 95%CI: 0.65-0.15, p=0.332). Conclusions: These preliminary results revealed no difference in 5-year OS between NACTS and CCRT, indicating that quality of life and long term toxicity are important to decide optimal treatment. The final results will be available by April 2019, including long-term toxicity and treatment effect across prognostic factors. Clinical trial information: NCT00039338.