Treatment Variation of Sequential versus Concurrent Chemoradiotherapy in Stage III Non-Small Cell Lung Cancer Patients in the Netherlands and Belgium

Aims Concurrent chemoradiotherapy (CCRT) is considered the standard treatment regimen in non-surgical locally advanced non-small cell lung cancer (NSCLC) patients and sequential chemoradiotherapy (SCRT) is recommended in patients who are unfit to receive CCRT or when the treatment volume is considered too large. In this study, we investigated the proportion of CCRT/SCRT in the Netherlands and Belgium. Furthermore, patient and disease characteristics associated with SCRT were assessed. Materials and methods An observational study was carried out with data from three independent national registries: the Belgian Cancer Registry (BCR), the Netherlands Cancer Registry (NCR) and the Dutch Lung Cancer Audit-Radiotherapy (DLCA-R). Differences in patient and disease characteristics between CCRT and SCRT were tested with unpaired t-tests (for continuous variables) and with chi-square tests (for categorical variables). A prognostic model was constructed to determine patient and disease parameters predictive for the choice of SCRT. Results This study included 350 patients from the BCR, 780 patients from the NCR and 428 patients from the DLCA-R. More than half of the stage III NSCLC patients in the Netherlands (55%) and in Belgium more than a third (35%) were treated with CCRT. In both the Dutch and Belgian population, higher age and more advanced N-stage were significantly associated with SCRT. Performance score, pulmonary function, comorbidities and tumour volume were not associated with SCRT. Conclusion In this observational population-based study, a large treatment variation in non-surgical stage III NSCLC patients was observed between and within the Netherlands and Belgium. Higher age and N-stage were significantly associated with the choice for SCRT.