Impact of first-line immunotherapy on survival and intracranial outcomes in a cohort of non-small cell lung cancer patients with brain metastases at diagnosis.

ABSTRACT

BACKGROUND: Although brain metastases (BM) at diagnosis are common in non-squamous NSCLC patients (ns-NSCLC), they have been mostly excluded from randomized trials. The aim of this retrospective study was to evaluate real-word outcomes of frontline immune checkpoint inhibitor (ICI) in these patients. METHODS: Our study assess the intracranial and overall efficacy of first-line ICI-based therapy compared to chemotherapy (CT) in ns-NSCLC patients diagnosed with BM, showing no targetable alterations. Patients were divided according to systemic therapy CT, ICI, or CT-ICI. Primary endpoint was overall survival (OS), compared using Kaplan-Meier and Cox methodology. Secondary endpoint was intracranial progression free survival (icPFS). RESULTS: Between 01 and 2018 and 05-2021, 118 patients were included (52 CT, 38 ICI and 28 CT-ICI). Median follow-up was 30.0 months. Intracranial radiotherapy was delivered for 75.0%, 68.4% and 67.9% of patients for CT, ICI and CT-ICI groups (p = 0.805). After adjustment, ICI and CT-ICI were associated with a better OS compared to CT (HR = 0.46, 95 %CI 0.23-0.89, and HR = 0.52, 95 %CI 0.27-1.01, respectively). ICI and CT-ICI were associated with a significant reduction in the risk of intracranial progression by 54% (HR = 0.46, 95 %CI 0.25-0.84) and 59% (HR = 0.41, 95 %CI 0.23-0.77) compared to CT. Stereotactic radiosurgery was associated with an increased icPFS compared to systemic therapy alone (HR = 0.51, 95% CI 0.29 - 0.92), whereas whole-brain was not. CONCLUSIONS: Real-life ns-NSCLC patients with BM at diagnosis treated frontline with ICI presented OS and icPFS benefit compared to CT alone. A prospective assessment of the ideal type and sequence of systemic and local therapy should be conducted.