Hypofractionated three-dimensional conformal radiation therapy alone for centrally located cT1-3N0 non-small-cell lung cancer

Abstract

Purpose: We retrospectively analyzed the treatment outcomes and toxicities by hypofractionated three-dimensional conformal radiation therapy (RT) alone in the patients with centrally located cT1-3N0 non-small-cell lung cancer (NSCLC).

Methods: Sixty patients with centrally located cT1-3N0 NSCLC received definitive RT alone at 3.0 Gy per fraction for either medical comorbidity or refusal of surgery, between January 2001 and December 2010. The central tumor was defined as being within 2 cm around the proximal bronchial tree. The median total dose was 60 (39-60) Gy.

Results: The local control (LC), overall survival (OS), and cause-specific survival rates at 2 and 5 years were 57.9%, 59.6%, 61.7%, and 50.1%, 33.5%, and 40.5%, respectively. Multivariate analyses showed that high cT stage (p = 0.007) and histology with NSCLC-not otherwise specified (p = 0.008) were the significantly unfavorable prognostic factors for OS, and that high cT stage (p = 0.031) and poor performance state (p = 0.007) were for LC. The LC rate at 2 years was 100% for cT1 tumor, 56.5% for cT2 tumor, and 28.6% for cT3 tumor, respectively. No patients experienced grade 3 or higher esophagitis, and three experienced grade 3 or higher pneumonitis.

Conclusion: Hypofractionated RT regimen for centrally located cT1-3N0 NSCLC proved safe with minimal toxicity, and, based on the excellent clinical outcomes in cT1 tumors, might serve as an alternative option for the patients who might not tolerate stereotactic body radiation therapy. As the clinical outcomes in cT2-3 tumors were still unsatisfactory, further dose intensifying regimen coupled with the use of concurrent systemic chemotherapy might be warranted.