Real-World Data on Once or Twice-Daily Radiation Therapy and the Effect of Age in Patients With Limited-Stage Small-Cell Lung Cancer.

PURPOSE: We aimed to assess acute toxicity and overall survival (OS) in patients with limited-stage small-cell lung cancer (LS-SCLC) who received concurrent thoracic chemoradiotherapy using either once-daily (OD) or twice-daily (BID) radiation therapy and compare these outcomes in 2 age groups.

METHODS AND MATERIALS: Data from the Dutch Lung Cancer Audit-Radiation therapy were prospectively recorded. Acute 90-day toxicity and OS in patients treated with OD and BID radiotherapy were compared in patients younger and older than 70 years. Survival was assessed in a multivariable Cox model. Acute toxicity was assessed in a multivariable logistic regression model.

RESULTS

Seven hundred eleven patients with LS-SCLC starting treatment between 2016 and 2023 were included. Mean age was 66.7 years (SD 8.5). In total, 59.8% of patients were younger than 70 years, of whom 85.2% were treated with a BID regimen. In younger patients treated BID, median OS was significantly longer (36.0 vs 22.2 months, adjusted hazard ratio, 0.61; 95% CI, 0.41-0.89, P = .01). In patients ≥70 years, 80.4% were treated BID. There was no difference in OS (21.8 vs 24.3 months; adjusted hazard ratio, 1.3; 95% CI, 0.76-2.28). No difference in acute toxicity was observed in younger patients treated BID (26.0%) versus OD (30.2%) (OR, 0.85; 95% CI, 0.41-1.84). Older patients treated BID had numerically higher toxicity (28.1%) compared with patients treated OD (19.5%) (OR 1.43; 95% CI, 0.57-3.77).

CONCLUSIONS

A significantly longer OS in younger patients with LS-SCLC treated with BID radiotherapy compared with OD was observed, without increase in acute 90-day toxicity. No difference in OS between regimens in patients 70 years or older was found.