Hypofractionated proton therapy for non-small cell lung cancer: Ready for prime time? A systematic review and meta-analysis.
This systematic review evaluated eight studies and 401 patients with early stage NSCLC treated with hypofractionated PBT to a median total dose of 63 Gy(RBE), with a median dose of 6.0 Gy(RBE) per fraction, resulting in a median BED of 105.6 Gy(RBE) to the target volumes. This analysis found that a BED ≥ 105.6 Gy(RBE) consistently provided superior OS, CSS, DFS and LC rates than BED < 105.6 Gy(RBE), however the probability of any late grade ≥ 2 adverse event was almost three-times greater for BED ≥ 105.6 Gy(RBE), with rib fractures being more common in the high dose group. The authors suggested that hypofractionated PBT can be considered as both safe and effective provided that advanced techniques for uncertainty management (e.g. respiratory motion gating, robust optimization) are implemented.