HypoRT with concurrent chemotherapy reduces treatment time and toxicity for patients with LS-SCLC

A multi-center, randomized phase III trial has found that a three-week hypofractionated radiotherapy (HypoRT) schedule with concurrent chemotherapy provides similar survival outcomes and reduced toxicity compared to the standard six-week conventional fractionated radiotherapy (ConvRT) schedule for patients with limited-stage small cell lung cancer (LS-SCLC).

The results were presented today at the International Association for the Study of Lung Cancer (IASLC) 2025 World Conference on Lung Cancer (WCLC).

In hypofractionated radiotherapy for lung cancer treatment, clinicians deliver fewer radiation treatments (fractions) at higher doses per session compared to standard radiotherapy schedules.

The study, conducted across 16 hospitals in China, randomized 530 patients to receive either HypoRT (45 Gy in 15 daily fractions over 3 weeks) or ConvRT (60 Gy in 30 daily fractions over 6 weeks), both given with concurrent cisplatin/carboplatin-etoposide chemotherapy. At a median follow-up of 43.4 months, median overall survival (OS) was 40.2 months in the HypoRT arm and 47.9 months in the ConvRT arm (HR=1.04; 95% CI, 0.81–1.33). Progression-free survival was also similar between the groups.

Patients receiving HypoRT experienced significantly fewer severe treatment-related adverse events including lower rates of hematologic toxicity, lymphopenia, and radiation pneumonitis. Acute grade ≥3 adverse events occurred in 48.7% of HypoRT patients compared to 67.7% in the ConvRT group.

Our findings suggest that hypofractionated radiotherapy can provide a shorter, more convenient treatment course with fewer side effects while maintaining comparable survival outcomes to conventional radiotherapy. This approach could be an important option for patients, especially in settings where reducing treatment time and toxicity is a priority."

Nan Bi, MD, The National Cancer Center of China/Cancer Hospital, Chinese Academy of Medical Sciences, Beijing

The investigators note that further research is warranted to explore HypoRT in combination with immunotherapy given its potential immune-sparing benefits.