Stage-Specific Guideline Concordant Treatment Impacts on Survival in Nonsmall Cell Lung Cancer: A Novel Quality Indicator

Background: Lung cancer in Australia contributes 9% of all new cancer diagnoses and is the leading cause of cancer death and burden. Clinical practice guidelines provide evidence-based treatment recommendations for best practice management. We aimed to determine the extent of delivery of guideline-concordant treatment (GCT) and to identify modifiable variables influencing receipt of GCT and survival. Methods: Data was sourced from the Victorian Lung Cancer Registry (VLCR) in Victoria, Australia. Descriptive statistics were used to summarize patient and disease characteristics according to treatment type: GCT versus non-GCT versus no/declined treatment. Statistical analyses included multiple logistic regression, multiple COX regression and Kaplan-Meier survival estimates. Results: 52% of patients were treated with GCT, 32.8% non-GCT and 15.2% declined or received no treatment. GCT treated patients were younger, never smoked, had no comorbidities, had better performance status, had early stage cancer, were discussed at a multidisciplinary meeting or had treatment at a higher volume hospital. Overall, patients that received GCT had a 24% lower risk of mortality compared to patients that received non-GCT. Conclusion: Modifiable variables impacting likelihood of receiving GCT included age, smoking status and treating hospital characteristics. Several modifiable variables were identified with positive impacts on survival including increased treatment of the elderly, smoking cessation, delivery of GCT, and treatment in higher volume hospitals. The measurement and reporting of delivery of GCT has positive impacts on survival and therefore merits consideration as an evidence-based quality indicator in the reporting of lung cancer quality and safety outcomes.