Published in JCO (Journal of Clinical Oncology), this randomized trial compared total toxicity burden (TTB) and progression-free survival (PFS) between PBT and IMRT for locally advanced esophageal cancer. 145 patients were randomly assigned (72 IMRT, 73 PBT), and 107 patients (61 IMRT, 46 PBT) were evaluable. Median follow-up was 44.1 months.

Fifty-one patients (30 IMRT, 21 PBT) underwent esophagectomy; 80% of PBT was passive scattering. This study reported the mean TTB was 2.3 times higher for IMRT (39.9) than PBT (17.4); the mean postoperative complications score was 7.6 times higher for IMRT (19.1) versus PBT (2.5); the 3-year PFS rate (50.8% v 51.2%) and 3-year overall survival rates (44.5% v 44.5%) were similar. This study concluded that for locally advanced esophageal cancer, PBT reduced the risk and severity of AEs compared with IMRT while maintaining similar PFS.