Escalating Thoracic Radiotherapy Dose May Improve Survival Without Added Toxicity in Limited-Stage Small-Cell Lung Cancer
Key Clinical Takeaways
- Design/Population: This phase 2 study enrolled 21 patients with pathologically confirmed limited-stage small-cell lung cancer (LS-SCLC) treated between 2013 and 2019. The median age was 70 years; 15 were male and 6 were female. Patients received accelerated hyperfractionated thoracic radiotherapy to a total dose of 54 Gy in 36 fractions over 3.6 weeks, delivered via 3D conformal radiotherapy (3D-CRT). Chemotherapy regimens included cisplatin plus etoposide or carboplatin plus etoposide.
- Key Outcomes: At a median follow-up of 57.3 months, 2- and 5-year overall survival (OS) rates were 85.7% and 47.6%, respectively, and 2- and 5-year progression-free survival (PFS) rates were 52.3% and 47.6%, respectively. No patients experienced grade ≥ 3 nonhematological toxicities during treatment or follow-up.
- Clinical Relevance: Escalating the hyperfractionated thoracic radiotherapy dose to 54 Gy resulted in favorable long-term OS and PFS without increasing severe toxicity, suggesting this regimen may be a promising radical treatment strategy for patients with LS-SCLC.
Results from a phase 2 study demonstrated that 54 Gy of accelerated hyperfractionated thoracic radiotherapy shows favorable long-term efficacy and safety among patients with limited-stage small-cell lung cancer (LS-SCLC).
According to Kanji Matsuura, MD, Hiroshima City Hiroshima Citizens Hospital, Hiroshima, Japan, and coauthors, “the combination of 45 Gy accelerated hyperfractionated thoracic radiotherapy and concurrent chemotherapy is the standard treatment for LS-SCLC…However, the optimal dose and fractionation remain controversial.”
In this study, 21 patients with pathologically confirmed LS-SCLC received 54 Gy of accelerated hyperfractionated thoracic radiotherapy over 3.6 weeks with concurrent cisplatin plus etoposide or carboplatin plus etoposide. All patients were treated with 3-dimensional conformal radiotherapy (3D-CRT) using multiple fields to minimize radiation exposure on surrounding tissues. Primary end points included overall survival (OS), progression-free survival (PFS), and nonhematological toxicity.
At a median follow-up of 57.3 months, the 2-year OS rate was 85.7% and the 2-year PFS rate was 52.3%. The 5-year OS and PFS rates were 47.6%. No grade ≥ 3 nonhematological adverse effects were reported during treatment or follow-up.
“These outcomes suggest that dose escalation to 54 Gy may be a promising radical treatment,” concluded Dr Matsuura et al.
Source:
Matsuura K, Komaki R, Kono M, et al. A phase II study of accelerated hyperfractionated thoracic radiotherapy with dose escalation to 54 Gy with concurrent cisplatin and etoposide for limited-stage small-cell lung cancer: Long-term results at a single institution. Clin Lung Cancer. Published online: September 19, 2025. doi: 10.1016/j.cllc.2025.09.003
