Adjuvant Gemcitabine Plus Cisplatin and Chemoradiation in Patients With Gallbladder Cancer

Abstract

ImportanceThere is limited evidence with regard to the benefit of adjuvant chemotherapy chemoradiotherapy in resected gallbladder cancers (GBCs).ObjectiveTo establish a baseline survival rate for operated GBCs in patients receiving either gemcitabine plus cisplatin (GC) or capecitabine and capecitabine concurrent with chemoradiation (CCRT).Design, Setting, and ParticipantsThe GECCOR-GB study was a multicenter, open-label, randomized phase 2 noncomparator “pick the winner” design trial of adjuvant GC and CCRT in patients with resected histologically confirmed adenocarcinoma or adenosquamous carcinoma of the gallbladder, (stage II/III) with no local residual tumor (R0) or microscopic residual tumor (R1). The study was carried out in 3 tertiary cancer institutions in India. Patients 18 years or older with adequate end-organ functions, and Eastern Cooperative Oncology Group Performance Status of 1 or lower between May 2019 and February 2022 were enrolled. The cutoff date for data analysis was February 28, 2023.InterventionsPatients were randomized 1:1 to receive either GC every 3 weeks (maximum of 6 cycles) or CCRT comprising capecitabine with concurrent chemoradiation (capecitabine concurrent with radiotherapy) sandwiched between capecitabine chemotherapy.Main Outcomes and MeasuresThe primary outcome was disease-free survival (DFS) at 1 year in randomized patients. This study was conducted as 2 parallel, single-stage phase 2 clinical trials. Within each treatment arm, a 1-year DFS rate of less than 59% was considered as insufficient activity, whereas a 1-year DFS rate of 77% or higher would be considered as sufficient activity.ResultsWith a median follow-up of 23 months, 90 patients were randomized, 45 in each arm. Overall, there were 31 women (69%) and 14 men (31%) in the GC arm with a mean (range) age of 56 (33-72) years and 34 women (76%) and 11 men (24%) in the CCRT group with a mean (range) age of 55 (26-69) years. In the GC and CCRT arms, 1-year DFS and estimated 2-year DFS was 88.9% (95% CI, 79.5-98.3) and 74.8% (95% CI, 60.4-89.2), and 77.8% (95% CI, 65.4-90.2) and 74.8% (95% CI, 59.9-86.3), respectively. Completion rates for planned treatment was 82% in the GC arm and 62% in the CCRT arm.Conclusions and RelevanceIn this randomized clinical trial, GC and CCRT crossed the prespecified trial end points of 1-year DFS in patients with resected stage II/III GBCs. The results set a baseline for a larger phase 3 trial evaluating both regimens in operated GBCs.Trial RegistrationClinicalTrials.gov Identifier: CTRI/2019/05/019323I