Treatment modalities and survival outcomes among elderly patients with stage IV small-cell lung cancer and synchronous brain metastases: A retrospective seer-based cohort study.

Objective

Chemotherapy improves survival in patients with lung cancer. However, the prognostic associations linked to chemotherapy remain unclear in elderly patients with stage IV small-cell lung cancer (SCLC) and brain metastases. This retrospective study was performed to explore the prognostic associations of different treatment modalities (chemoradiotherapy, chemotherapy alone, no treatment) in elderly patients aged ≥ 75 years with stage IV SCLC and brain metastases, and to provide evidence-based support for individualized clinical decision-making.

Methods

Clinical data of elderly patients aged ≥ 75 years diagnosed with stage IV SCLC and synchronous brain metastases between 2004 and 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Patients were divided into three groups: chemoradiotherapy, chemotherapy alone, and no treatment. The primary endpoint was overall survival (OS), and the secondary endpoint was lung cancer-specific survival (LCSS). Statistical analyses were performed using the Kaplan-Meier method, log-rank test, and multivariable Cox proportional hazards regression model.

Results

A total of 573 patients were included: 332 (57.94%) in the chemoradiotherapy group, 110 (19.20%) in the chemotherapy group, and 131 (22.86%) in the no treatment group. The 1-year OS rates were 18.07% (95% CI: 14.37%-22.72%) in the chemoradiotherapy group, 18.18% (95% CI: 12.23%-27.03%) in the chemotherapy group, and 3.05% (95% CI: 1.16%-8.01%) in the no treatment group (P < 0.001). Median OS was 5.5 months (95% CI: 5-6), 5.0 months (95% CI: 4-6), and 1.5 months (95% CI: 1-2), respectively (P < 0.0001). In multivariable analysis, receipt of chemotherapy was independently associated with longer OS after adjustment for available covariates. Compared with no treatment, chemoradiotherapy (HR = 0.36, 95% CI: 0.29-0.45, P < 0.001) and chemotherapy alone (HR = 0.37, 95% CI: 0.28-0.48, P < 0.001) were correlated with lower mortality hazard. Similar survival correlations of chemotherapy remained consistent across age subgroups: 75-79 years (HR = 0.342, 95% CI: 0.240-0.487, P < 0.0001), 80-84 years (HR = 0.402, 95% CI: 0.238-0.679, P < 0.0001), and even ≥ 85 years (HR = 0.375, 95% CI: 0.158-0.892, P < 0.05).

Conclusion

The receipt of chemotherapy was associated with significantly longer OS in elderly patients aged ≥ 75 years with stage IV SCLC and brain metastases. Systemic chemotherapy may be a reasonable alternative for appropriately selected elderly patients, but individualization based on comprehensive geriatric assessment is essential. Withholding active treatment was associated with an extremely high risk of unfavorable survival outcomes in this observational dataset.