Radiat Oncol J.  2023 Sep;41(3):199-208. 10.3857/roj.2023.00591.

Outcome of dose-escalated intensity-modulated radiotherapy for limited disease small cell lung cancer

• Yang E
• Shin YS
• Joo JH
• Choi W
• Kim SS
• Choi EK
• Lee J
• Song SY

• KMID: 2546213
• DOI: http://doi.org/10.3857/roj.2023.00591

Abstract

Purpose
An optimal once-daily radiotherapy (RT) regimen is under investigation for definitive concurrent chemoradiotherapy (CCRT) in limited disease small cell lung cancer (LD-SCLC). We compared the efficacy and safety of dose escalation with intensity-modulated radiotherapy (IMRT).
Materials and Methods
Between January 2016 and March 2021, patients treated with definitive CCRT for LD-SCLC with IMRT were retrospectively reviewed. Patients who received a total dose <50 Gy or those with a history of thoracic RT or surgery were excluded. The patients were divided into two groups (standard and dose-escalated) based on the total biologically effective dose (BED, α/β = 10) of 70 Gy. The chemotherapeutic regimen comprised four cycles of etoposide and cisplatin.
Results
One hundred and twenty-two patients were analyzed and the median follow-up was 27.8 months (range, 4.4 to 76.9 months). The median age of the patients was 63 years (range, 35 to 78 years) and the majority had a history of smoking (86.0%). The 1- and 3-year overall survival rates of the escalated dose group were significantly higher than those of the standard group (93.5% and 50.5% vs. 76.7% and 33.3%, respectively; p = 0.008), as were the 1- and 3-year freedom from in-field failure rates (91.4% and 66.5% vs. 73.8% and 46.9%, respectively; p = 0.018). The incidence of grade 2 or higher acute and late pneumonitis was not significantly different between the two groups (p = 0.062, 0.185).
Conclusion
Dose-escalated once-daily CCRT with IMRT led to improved locoregional control and survival, with no increase in toxicity.

Keyword

Small cell lung cancer; Limited disease; Radiotherapy; Dose escalation; Once-daily; Intensity-modulated radiotherapy