PQA 04 - PQA 04 Palliative Care and Central Nervous System Poster Q&A
2489 - Comparison of Distant Intracranial Disease Control between Central Nervous System-Penetrating Tyrosine Kinase Inhibitors and Immunotherapy in Non-Small Cell Lung Cancer Metastatic to Brain Following S
Kaiser Permanente Los Angeles Medical Center Los Angeles, CA
A. Beighley1, S. Iganej2, I. Abdalla3, F. Dayani4, J. Rahimian2, M. Cohen5, J. P. Vinci1, K. Lodin2, M. R. Girvigian2, and O. Bhattasali2; 1Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA, 2Southern California Permanente Medical Group, Los Angeles, CA, 3Kaiser Permanente, Southern California Medical Group, Los Angeles, CA, 4Kaiser Permanente Los Angeles Medical Center Residency Program, Los Angeles, CA, 5Kaiser Permanente, Southern California, Los Angeles, CA
Purpose/Objective(s): Systemic therapy may impact intracranial metastatic disease directly through blood brain barrier penetration or indirectly by controlling extracranial disease and limiting further intracranial seeding. We evaluated the differential impact of central nervous system-penetrating tyrosine kinase inhibitors (CP-TKI) and immunotherapy (IO) on distant intracranial disease control in patients with non-small cell lung cancer (NSCLC) with brain metastases (BM) treated with stereotactic radiosurgery (SRS). Materials/
Methods: A retrospective study was conducted of 120 patients with NSCLC with BM treated with SRS between November 2016 and December 2022 without preceding surgery or whole brain radiotherapy (WBRT). Distant cranial failure-free survival (DCFFS), WBRT-free survival (WBRTFS), and overall survival (OS) were evaluated and compared in multivariable analyses adjusted for clinical prognostic factors. Results: Median follow up was 15.9 months (range: 0.4-79.2). Median patient age was 67 years (range: 24-92). EGFR and ALK mutations were noted in 30 (25.0%) and 10 (7.5%) of patients, respectively, and PD-L1 expression >1% in 63 (52.1%) of patients. Twenty-two (18.3%) patients received CP-TKI, 58 (48.3%) received IO, and 6 (5.0%) received both CP-TKI and IO. Median number of SRS sessions was 1 (range: 1-6), and median total number of lesions treated was 3 (range: 1-30). Median DCFFS, WBRTFS, and OS for the entire cohort were 7.1 months, 14.7 months, and 16.2 months, respectively. Uncontrolled extracranial disease (p=0.001) and initial number of BM (p=0.03) were both associated with inferior DCFFS, while initial volume of BM (p=0.22) was not. Receipt of CP-TKI was associated with improved median DCFFS (26.1 v. 5.9 months, p=0.001), WBRTFS (31.3 v. 10.5 months, p=0.01), and OS (31.7 v. 11.1 months, p=0.005). Among patients who did not receive CP-TKI, receipt of IO was associated with improved median DCFFS (7.1 v. 3.3 months, p=0.04). WBRTFS (15.9 v. 4.1 months, p=0.03) and OS (16.4 v. 4.1 months, p=0.03). When comparing patients who received CP-TKI without IO to those receiving IO without CP-TKI, CP-TKI was associated with improved median DCFFS (14.4 v. 7.1 months, p=0.02) but no difference in WBRTFS (26.2 v. 15.9 months, p=0.16) or OS (29.2 v. 16.4 months, p=0.09). Conclusion: Receipt of CP-TKI resulted in a greater than four-fold improvement in median DCFFS and nearly three-fold improvement in median WBRTFS and OS in patients with NSCLC with BM following upfront SRS. Among patients not receiving CP-TKI, IO was associated with improved DCFFS, WBRTFS, and OS, albeit to a smaller magnitude; however, IO demonstrated inferior DCFFS when compared to CP-TKI. This study further supports the role of CP-TKI in management of NSCLC with BM.