This MD Anderson study compared IMRT and PBT chemoradiation for esophageal cancer. Patients who had IMRT and PBT matched by propensity score (n = 220) were not different with respect to age, sex, stage, performance status, tumor location, histology, tumor target volume, or induction chemotherapy.

This study found that IMRT, compared to PBT, was associated with increased risk of grade 4 lymphopenia in patients with greater target volume, and PBT reduces the risk of severe, treatment-related lymphopenia, particularly in tumors of the lower esophagus.