Abstract

Stereotactic ablative radiotherapy (SABR) results in high rates of primary tumor control for early-stage non-small cell lung cancer (NSCLC). For patients with isolated hilar or mediastinal nodal recurrences (INR) after SABR, the optimal salvage treatment strategy is unclear. The purpose of this study is to determine the rate of INR after SABR for early-stage NSCLC and to describe patterns of care and treatment outcomes after salvage therapy.This retrospective cohort study included 342 patients with Stage T1-3N0M0 NSCLC treated with definitive SABR from 2003-2018. We evaluated the incidence of INR and baseline factors between patients who did and did not experience INR. Among patients who experienced INR, we described treatment patterns and outcomes including overall (OS) and progression free survival (PFS) from the time of nodal failure using the Kaplan-Meier method.With a median follow-up of 3.3 years, the 3-year INR rate was 10.6% (6.6% -13.4%). Among the 34 patients experiencing INR, the 3-year rates of OS and PFS were 39.3% (24.4 - 63.3%) and 26.7% (14.1 - 50.3%), respectively. The 34 patients with INR were treated with RT alone (26.7 %), concurrent chemoradiotherapy (CRT) (43.3 %), chemotherapy alone (13.3%), or observation (16.7%). CRT had the best survival outcomes with a 3-year OS and PFS of 81.5% (61.1 - 100.0%) and 63.9% (40.7 - 100.0%), respectively. Of the patients treated with salvage RT or CRT, 14.3% experienced grade 3 toxicity with no patients having grade 4+ toxicity.INR occurred in approximately 10% of patients treated with SABR for early-stage NSCLC. The highest rates of OS an PFS among patients with INR were observed in those treated with salvage chemoradiotherapy.

View details for DOI 10.1016/j.prro.2022.06.013

View details for PubMedID 35858658