Early Mortality After Curative-intent Radiotherapy in Patients With Locally Advanced Non-small Cell Lung Cancer-A Population-based Cohort Study.

Aims: In patients with locally advanced non-small cell lung cancer (LA-NSCLC), curative-intent radiotherapy (RT) or chemoradiotherapy (CRT) is associated with considerable toxicity, and approximately half of the patients die within two years. A better understanding of early mortality is needed to improve patient selection and guide supportive interventions. In this population-based, nationwide cohort study, we investigated the incidence, temporal distribution, and risk factors of early mortality.

Materials and methods: Patients with stage II-III NSCLC treated with curative-intent RT/CRT in Denmark from 2010-2017 were included. Patients treated with preoperative or postoperative RT/CRT or stereotactic body radiation therapy were excluded. Early mortality was defined as all-cause death within 180 days from RT/CRT initiation. Multiple logistic regression was used to assess the impact of clinical and demographic variables.

Results: We included 1742 patients. The early mortality rate was 10%. The temporal distribution of deaths was uniform across the first year following RT/CRT, indicating the absence of a high-risk period. In multivariable analysis, increasing age and performance status, male sex, and unspecified histology (NSCLC not otherwise specified) were associated with an increased risk. By contrast, the Charlson Comorbidity Index (CCI), TNM stage, and treatment period did not significantly alter the risk of early mortality. Overall survival rates improved throughout the inclusion period but early mortality rates did not.

Conclusion: No high-risk period for early mortality could be identified. Early mortality was not associated with CCI and other tools should be explored to quantify comorbidity for risk stratification in this setting.