Efficacy and Safety of Four Weeks of Moderately Hypofractionated Chemoradiation for Unresectable, Stage 3 Non-Small Cell Lung Cancer: A Systematic Review.

Shortening treatment time with moderately hypofractionated radiotherapy benefits patients by reducing inconvenience and costs, but its use in the definitive treatment of unresectable Stage 3 non-small cell lung cancer is controversial due to lack of level one evidence and toxicity concerns. Pivotal systemic therapy trials utilize conventionally fractionated chemoradiation at 2 Gy per fraction given over 6 weeks. In practice, 4 weeks of chemoradiation at 2.75 Gy per fraction is sometimes employed to reduce the treatment burden for selected patients, especially those who are older or have comorbidities. It is uncertain if the two fractionation regimens are similar in biological effectiveness, especially with varying systemic therapy. This systematic review aimed to collate the survival and toxicity outcomes for 4 weeks of moderately hypofractionated chemoradiation, using > 50 -60 Gy in 20 fractions. Eight studies met the eligibility criteria; seven studies were from a database search of MEDLINE, EMBASE, Cochrane Library, and Web of Science and one study was added later. Two studies were prospective randomized trials and six were retrospective cohort studies. No study included immunotherapy. The historical evidence has been limited, but emerging data is promising, especially when compared to outcomes of standard chemoradiation. Thus, further investigation of this strategy is justified.