In an individual patient meta-analysis of the BC2001 and BCON trials (Choudhury et al, Lancet Oncol, 2021), two fractionation schedules for locally advanced bladder cancer were compared; 64 Gy/32 fx vs 55 Gy/20 fx.
BC2001 originally tested the addition of chemotherapy to radiotherapy, and BCON tested hypoxia-modifying therapy combined with radiotherapy.
Co-primary endpoints of the meta-analysis were invasive locoregional control and late bladder/rectum toxicity. ~800 patients were included and the median follow-up was 120 months.
Patients who received 55 Gy/20 fx had a lower risk of invasive locoregional control (adjusted HR 0.71) and a similar toxicity profile when compared to 64 Gy/32 fx.
Clinical Pearl: 55 Gy/20 fx hypofractionated RT provides non-inferior, and in fact superior, invasive locoregional control with similar toxicity to 64 Gy/32 fx in locally advanced bladder cancer.