CNS Metastases in Epidermal Growth Factor Receptor Mutation–Positive Non–Small-Cell Lung Cancer: Impact on Health Resource Utilization

Abstract

Purpose: Patients with epidermal growth factor receptor (EGFR) mutation–positive (EGFRm) non–small-cell lung cancer commonly experience disease progression in the CNS. Here, we assess the impact of CNS disease on resource utilization and outcomes in patients who are EGFRm. Methods: We completed a retrospective review of all advanced patients who were EGFRm, referred to BC Cancer, and treated with a first- and/or second-generation EGFR tyrosine kinase inhibitor from 2010 to 2015. Baseline characteristics, systemic treatment, and CNS management were collected. We compared health resource utilization (HRU) between patients with CNS-negative disease and those with CNS metastases from the median time of CNS metastases diagnosis to death or last follow-up (9.1 months) and at 9 months preceding death or last follow-up for the CNS-negative group. Results: Four hundred ninety-nine patients were referred, of which 68% were female; 51% were of Asian ethnicity; and 57%, 37%, and 6% were exon 19, 21, or other, respectively; with a median age of 66 years. Two hundred twenty-nine (46%) of 499 patients developed CNS metastases—39% at diagnosis and 61% over the course of disease. CNS metastases were managed with surgery with or without whole-brain radiotherapy (WBRT; 13%) WBRT alone (73%), stereotactic radiosurgery with or without WBRT (5%), or no CNS-directed therapy (9%). The median time from the development of CNS metastases diagnosis to death was 9.1 months. CNS-negative patients used less HRU versus patients that were CNS-positive in the 9 months preceding death or last follow-up—in the average number of clinic visits (8.53 v 12.71, respectively; P < .001), hospitalizations (0.43 v 0.76, respectively; P < .001), CNS imaging investigations (0.52 v 2.65, respectively; P < .001), emergency room visits (0.03 v 0.14, respectively; P = .001), palliative care unit admission (8% v 10%, respectively; P = .64), and hospice admission (3% v 19%, respectively; P < .001). Conclusion: The incidence of CNS metastases in patients with EGFRm is high and associated with increased HRU. Prevention or delay of CNS metastases with newer systemic therapy options may translate into lower resource utilization.