Analysis of Relapse Events After Definitive Chemoradiotherapy in Locally Advanced Non-Small-Cell Lung Cancer Patients.

Background: The appropriate follow-up frequency after definitive chemoradiotherapy (CRT) for locally advanced non-small-cell lung cancer patients is unknown. Although surveillance guidelines have been proposed, very few data support current recommendations. Here we analyze relapse events after CRT and investigate whether symptomatic relapses versus those detected by surveillance imaging influences outcomes.
Patients and Methods: Stage III non-small-cell lung cancer patients treated with CRT at our institution between 2005 and 2014 were retrospectively analyzed. Relapse events were grouped into posttreatment intervals and analyzed with cumulative tables. Time to relapse and overall survival (OS) were compared between patients with relapse detection via symptomatic presentation versus surveillance imaging.
Results: A total of 211 patients were identified for analysis. The median follow-up was 43 months for patients alive at the time of analysis. The median age was 63 years, and equal proportions had IIIA or IIIB disease. A total of 135 patients (64%) experienced disease relapse, and of these, 74% did so within 12 months. In those who did not experience relapse at ≤ 12 months, 16%, 6%, and < 5% experienced relapse during 12 to 24, 24 to 36, and > 36 months of follow-up, respectively. In patients with relapse, 56% presented symptomatically, which led to inferior median OS compared to those identified by surveillance imaging (23 vs. 36 months; P = .013).
Conclusion: This study identified that most relapses occur within 1 year of completing CRT, and approximately half of these occur within 6 months. A symptomatic relapse led to inferior OS. More aggressive surveillance imaging may therefore identify asymptomatic relapses that are amenable to earlier salvage therapy.
(Copyright © 2018 Elsevier Inc. All rights reserved.)