A Randomized Study of Consolidation Chemoradiation (CTRT) versus Observation after first line chemotherapy (CT) in Advanced Gall bladder Cancers (GBC):RACE-GB study.

Purpose: CT is the standard of care for patients presenting with unresectable advanced GBC but their prognosis remains poor. The value of consolidation CTRT after initial CT is uncertain. We therefore conducted a single centre open label randomised trial evaluating consolidation CTRT versus Observation after four cycles of CT in patients whose disease did not progress during CT (partial responders/stable disease).

Materials & methods: Responders to 4 cycles of CT were randomised (1:1) to CTRT versus Observation (n=135). CTRT was delivered by 3D-Conformal Radiation Therapy (Field in field when required) along-with concurrent capecitabine. The dose of RT was 45 Gy in 25 fractions to GBC and lymphatics followed by a boost of 9 Gy in 5 fractions to the GBC. The primary endpoint was overall survival which was calculated from the date of randomisation.

Results: 67 patients were randomized to observation and 68 to CTRT. Consolidation CTRT led to an improvement in median overall survival from 4 months to 10 months (HR 0.43; 95% CI, 0.32 to 0.62; P < 0.001). The actual median OS from accrual was 7 months (95%CI 6.114 to 7.88) versus 13 months (95% CI 11.13 months to 14.84 months). Adverse events (grade 3 or higher) due to CTRT were nausea: 3%, anaemia: 9%, GI bleed: 5.8%, hepatotoxicity:13%. FACT G score and FACT Hep score did not deteriorate due to CTRT as compared to observation (p value 0.053 and 0.097).

Conclusion: To our knowledge, this is the first-ever randomized study in LMIC setting to demonstrate that consolidation CTRT significantly prolonged overall survival without deterioration in QOL and should be the alternative standard of care in advanced unresectable GBC.