Targeted Therapies and Utility of the Lung-molGPA in Non-Small-Cell Lung Cancer Patients with Brain Metastases

Abstract

Introduction: Therapeutic advances have increased the survival of non-small-cell lung cancer (NSCLC) patients as well as the lifetime risk of being diagnosed with brain metastases (BM). Although BM have historically been associated with poor prognosis, it is unclear whether they remain a strong predictor of reduced survival. This study aimed to evaluate the prognostic value of BM and the utility of the Lung-molGPA.

Methods: This single-center retrospective database analysis included 1,393 NSCLC patients with newly diagnosed BM who registered at the Instituto Nacional de Cancerología of Mexico (INCan) from 2010 to 2020. The Kaplan-Meier method and log-rank test were used for the survival analysis. Survival times were calculated from the date of NSCLC diagnosis (OS), or BM diagnosis, to the date of death or last follow-up. Cox proportional-hazards models were used to calculate the hazard ratio (HR) for death and the significance of the parameters evaluated.

Results: Out of 1,058 patients who underwent genetic testing for epidermal growth factor receptor (EGFR) mutations and/or anaplastic lymphoma kinase (ALK) rearrangements, 650 had a positive tumor mutational/rearrangement status (543 had EGFR mutations, 104 had ALK rearrangements, and 3 had both EGFR and ALK alterations). Median OS did not differ between patients with BM and without BM (17.7 months [95% CI, 15.4-19.0] vs. 16.6 months [95% CI, 14.3-19.0]; p = 0.362). In contrast, the presence of BM was associated with worse OS in patients with a negative tumor mutational status (HR: 1.225 [95% CI, 1.041-1.443]; p = 0.015), who did not receive TKI therapy (HR: 1.269 [95% CI, 1.082-1.488]; p = 0.003), or with non-adenocarcinoma histology (HR: 1.582 [95% CI, 1.118-2.238]; p = 0.01). The median survival after BM diagnosis was 4.27, 6.96, 14.68, and 18.89 months for adenocarcinoma patients with Lung-molGPA scores 0-1, 1.5-2, 2.5-3, and 3.5-4, respectively (p < 0.0001). For non-adenocarcinoma patients with Lung-molGPA scores 0-1, 1.5-2, and 2.5-3, the corresponding estimates were 0.95, 2.89, and 9.39 months, respectively (p < 0.0001).

Conclusions: These results show that the prognosis of NSCLC patients with BM is no longer uniformly poor and should be individually assessed. Furthermore, the validity of the Lung-molGPA was confirmed in an independent population from a different geographical region.

Keywords: Brain metastases; Non-small-cell lung cancer; Prognosis; Targeted therapy.