Stereotactic versus Standard Tumor Irradiation in unresectable Locally Advanced NSCLC with Durvalumab Maintenance: A Multicenter Study with propensity score matching
Menée à partir de données multicentriques portant sur 208 patients atteints d'un cancer du poumon non à petites cellules de stade localement avancé et non résécable (durée médiane de suivi : 38 mois ; âge médian : 64 ans), cette étude analyse l'efficacité d'une radiothérapie stéréotaxique ciblant la tumeur primitive par rapport à une chimioradiothérapie avec fractionnement conventionnel suivie d'une immunothérapie
Background: Tumor control in locally advanced non-small cell lung cancer (LA-NSCLC) is associated with patient prognosis, sustaining ongoing research in dose escalation strategies. This study evaluates the efficacy and safety of tumor SBRT (T-SBRT) compared to tumoral normofractionated chemoradiotherapy followed by immunotherapy.
Methods: This retrospective multicenter study included patients with unresectable LA-NSCLC treated between July 2017 and January 2023. Eligible patients received ≥60 Gy normofractionated radiotherapy (NFRT), ≥1 cycle of chemotherapy, and ≥1 cycle of durvalumab. The T-SBRT group received mediastinal NFRT and ultra-hypofractionated primary tumor irradiation. Propensity score matching (PSM) was performed to limit confounding effects.
Results: Among the 208 included patients, 21 (10%) received T-SBRT. Median age was 64.0 years, most had adenocarcinoma (59.1%). There were no differences in patients’ characteristics except stages and T stages (not observed in T stage after PSM). Most frequent SBRT regimen was 50 Gy in 5 fractions (28.6%). After a median follow-up of 38 months (95%CI 26.0-57.0), T-SBRT was associated with longer PFS in overall cohort (median not reached vs 22.8 months; HR=0.46, 95%CI 0.21-0.99, p=0.046), and after PSM (HR=0.41, 95%CI 0.18-0.92, p=0.031). T-SBRT also tended to be associated with longer OS in both overall and PSM cohorts (HR=0.54, 95%CI 0.22-1.33, p=0.18 and HR=0.46, 95%CI 0.18-1.18, p=0.11, respectively). Acute grade 3 toxicities were comparable, without grade 4-5 events. However, given the limited number of patients, these results should be interpreted with caution and considered exploratory.
Conclusion: T-SBRT in LA-NSCLC is significantly associated with longer PFS with a trend towards prolonged OS, without increasing toxicity. Further studies are needed to refine optimal timing and immunologic synergy.
International Journal of Radiation Oncology, Biology, Physics , résumé, 2025