Sequencing of Stereotactic Body Radiation Therapy and Chemotherapy in Stage I Small Cell Lung Cancer: Practice Patterns and Outcomes

Purpose

We evaluated practice patterns and survival outcomes associated with the sequencing of stereotactic body radiation therapy (SBRT) and chemotherapy in patients with clinical stage I small cell lung cancer (SCLC) in the United States. Methods and Materials: Using a large national database, we identified patients with clinical stage I (cT1-2N0M0) SCLC treated with SBRT and chemotherapy between 2004 and 2020. To assess practice patterns in relation to survival outcomes, patients were categorized into 2 cohorts: “SBRT before chemotherapy” and “SBRT concurrent with or after chemotherapy.” χ 2 tests and logistic regression models were used to determine patient characteristics associated with treatment sequencing. Univariable and multivariable Cox proportional hazard models were used to assess the association between patient characteristics and survival outcomes. Overall survival was analyzed using the Kaplan-Meier method and compared via the log-rank test. Sensitivity analyses were performed using multivariable logistic regressions and Cox proportional hazards models for treatments with a 30-day overlap and clinical T stage stratification.