A phase III randomised clinical trial of perioperative therapy (neoadjuvant chemotherapy versus chemoradiotherapy) in locally advanced gallbladder cancers (POLCAGB): study protocol

INTRODUCTION: Neoadjuvant chemotherapy (NACT) is considered the current standard for locally advanced gallbladder cancer (GBC). There is no consensus on the optimal neoadjuvant approach. A pilot study from our institution has shown improved overall survival (OS) and progression-free survival (PFS) with neoadjuvant chemoradiation (NACRT). The present randomised phase III trial is designed to compare NACRT with NACT alone and will test the superiority of chemoradiation in terms of tumour downstaging and improvement in OS. METHODS AND ANALYSIS: Patients with biopsy-proven locally advanced GBC (T3-4) with predefined clinical-radiological features will be randomised to the gemcitabine-based chemotherapy-alone arm or the chemoradiation arm. Patients with resectable disease or with distant metastases will be excluded. The primary end point of the study is to compare OS between the two arms. The secondary end point was to compare PFS, R0 resection rates, acute and late toxicity, postoperative complications and quality of life between the two study arms. The trial is designed to detect an improvement in median OS by 5.5 months in the study arm (11 months in the control group, HR of 0.7) with 80.0% power at a 0.05 significance level. The resultant sample size to achieve this aim is 314 (157 in each arm) over a duration of 5 years with a 10% attrition rate. ETHICS AND DISSEMINATION: The institutional ethics committee has approved this trial and will be routinely monitoring the trial at frequent intervals. The results of the study will be disseminated via peer-reviewed scientific journals, conference presentations and submission to regulatory authorities. REGISTRATION: The trial is registered with Clinical Trials Registry India (CTRI/2016/08/007199) and ClinicalTrials.gov (NCT02867865). This trial aims to assess the superiority of NACRT over NACT in locally advanced GBCs in terms of improvement in OS. The results of this study will define the optimal neoadjuvant approach in locally advanced GBC. TRIAL REGISTRATION NUMBER: NCT02867865; Pre-results.