Brain Metastasis Incidence and Patterns of Presentation After Definitive Treatment of Locally Advanced Non-Small Cell Lung Cancer: A Potential Argument for Brain Magnetic Resonance Imaging Surveillance

Joshua C Farris; Ryan T Hughes; Niema B Razavian; Jane B Pearce; Anna C Snavely; Michael D Chan; Cole R Steber; C Marc Leyrer; Paul M Bunch; Jeffrey S Willey; Michael K Farris

doi:10.1016/j.adro.2022.101058

Brain Metastasis Incidence and Patterns of Presentation After Definitive Treatment of Locally Advanced Non-Small Cell Lung Cancer: A Potential Argument for Brain Magnetic Resonance Imaging Surveillance

Adv Radiat Oncol. 2022 Oct 23;8(3):101058. doi: 10.1016/j.adro.2022.101058. eCollection 2023 May-Jun.

Affiliations

¹ Department of Radiation Oncology, Wake Forest School of Medicine, Winston Salem, North Carolina.
² Department of Biostatistics and Data Science, Wake Forest School of Medicine, Winston Salem, North Carolina.
³ Department of Radiology, Wake Forest School of Medicine, Winston Salem, North Carolina.

Abstract

Purpose: Brain metastases (BMs) are a common source of morbidity and mortality. Guidelines do not advise brain surveillance for locally advanced non-small cell lung cancer (LA-NSCLC). We describe the incidence, time to development, presentation, and management of BMs after definitive chemoradiotherapy (CRT).

Methods and materials: We reviewed records of patients with LA-NSCLC treated with CRT within the period from 2013 to 2020. Descriptive statistics were used to characterize the population and the Kaplan-Meier method was used to estimate time to BM. Fisher exact tests and Wilcoxon rank-sum tests were used to compare outcomes between symptomatic and asymptomatic patients.

Results: A total of 219 patients were reviewed including 96 with squamous cell carcinoma, 88 with adenocarcinoma, and 35 with large cell/not otherwise specified (LC/NOS). Thirty-nine patients (17.8%) developed BMs: 35 (90%) symptomatic and 4 (10%) asymptomatic. The rate of BM was highest in LC/NOS (34.3%) and adenocarcinoma (23.9%). Ninety percent of BMs occurred within 2 years. All asymptomatic patients underwent stereotactic radiosurgery alone, compared with 40% of symptomatic patients (P = .04). Symptomatic patients were more likely to require hospitalization (65.7% vs 0%, P = .02), craniotomy (25.7% vs 0%, not significant), and steroids (91.4% vs 0%, P < .001). Cumulative BM volume was higher for symptomatic patients (4 vs 0.24 cm³, P < .001) as was median greatest axial dimension (2.18 vs 0.52 cm, P < .001).

Conclusions: We identified a high rate of BMs, particularly in LC/NOS and adenocarcinoma histology NSCLC. The majority were symptomatic. These results provide rationale for post-CRT magnetic resonance imaging brain surveillance for patients at high risk of BM.