Hypofractionated Radiotherapy Combined with Immunotherapy for Limited-stage Small-cell Lung Cancer

Concurrent chemoradiotherapy has long been the standard modality for locally advanced small-cell lung cancer, which could achieve median overall survival of 25 mos. Conventional fractionation of 66Gy/33f and hyperfractionation of 45Gy/30f twice daily have been acknowledged as the two standard radiotherapy modalities according to CONVERT study. With the introduction of immune checkpoint inhibitors, ADRIATIC study concluded that consolidative Durvalumab after concurrent chemoradiotherapy could achieve a far longer median overall survival of 55.9 months compared with 33.4 months for concurrent chemoradiotherapy. Recently, several studies have demonstrated the safety and efficacy of hypofractionated radiotherapy (3 to 4 Gy) for limited-stage small-cell lung cancer. Hypofractionated radiotherapy processes the advantage of short treatment duration compared with conventional fractionated radiotherapy, which may allow the early participation of immunotherapy. Therefore, we suppose that whether hypofractionated radiotherapy combined with immunotherapy could improve the survival of limited-stage of small-cell lung cancer.