Shrivastava S, et al. - With an intent to determine the benefit of concurrent chemoradiotherapy (CT-RT) in International Federation of Gynecology and Obstetrics (FIGO) stage IIIB squamous cell carcinoma of the uterine cervix, researchers herein present the final results of a randomized clinical trial of concurrent cisplatin-based CT-RT and radiotherapy alone (RT) in women with FIGO stage IIIB squamous cell carcinoma of the uterine cervix. Significantly better disease-free survival (DFS) and overall survival (OS) were noted in women who received chemoradiotherapy using weekly cisplatin, compared with RT, for stage IIIB squamous cell carcinoma of the uterine cervix. This study provides level 1 evidence in the largest clinical trial reported so far in favor of concurrent weekly cisplatin chemotherapy in this setting.

• This single-institution study was conducted at a tertiary cancer center setting.
• In this phase 3 open-label randomized clinical trial, a total of 850 women were accrued in Mumbai, India, between July 7, 2003, and September 22, 2011.
• Using block randomization (1:1), a total of 850 of 2121 screened women with FIGO stage IIIB squamous cell carcinoma of the uterine cervix suitable for concurrent cisplatin chemotherapy were randomly assigned to receive RT (RT arm), comprising a combination of external beam RT (50 Gy in 25 fractions over 5 weeks) and brachytherapy, or to receive in addition to the same RT concurrent weekly cisplatin chemotherapy (40 mg/m² per week) (CT-RT arm).
• The data were updated for a minimum follow-up period of 5 years until December 2016.
• Researchers undertook final analyses in February and March 2017.
• The primary end point was 5-year disease-free survival (DFS), defined as the time between the date of randomization and the date of any recurrence or death (whichever occurred first) in the intent-to-treat population.

• A total of 424 women assigned to CT-RT (mean [SD] age, 49.4 [7.9] years) and 426 women assigned to RT (mean [SD] age, 49.3 [7.9] years) were included in this study.
• Total 222 recurrences and 213 deaths in the CT-RT arm and 252 recurrences and 243 deaths in the RT arm were reported at a median follow-up of 88 months (interquartile range, 61.3-113.1 months).
• Significantly higher 5-year DFS was observed in the CT-RT arm (52.3%; 95% CI, 52.2%-52.4%) vs in the RT arm (43.8%; 95% CI, 43.7%-43.9%), with a hazard ratio for relapse or death of 0.81 (95% CI, 0.68-0.98) (P=.03).
• Similarly, significantly higher 5-year overall survival (OS) was observed in the CT-RT arm (54.0%; 95% CI, 53.9%-54.1%) compared with the RT arm (46.0%; 95% CI, 45.9%-46.1%), with a hazard ratio for death of 0.82 (95% CI, 0.68-0.98; P=.04).
• CT-RT continued to be significantly superior to RT for DFS and OS, as observed after adjusting for prognostic factors.
• In addition, in the CT-RT arm, a higher incidence of acute hematological adverse effects was reported.