Guideline concordance of stage IIIA non-small-cell lung cancer treatment in the Australian setting

Stage IIIA non-small-cell lung cancer (NSCLC) is a life-limiting disease, and the level of adherence to evidence-based treatment guidelines in the Australian setting is unclear.

To assess the level of adherence to stage IIIA NSCLC treatment guidelines prior to the advent of immunotherapy and highlight factors that may contribute to guideline non-concordance.

A retrospective cohort study was performed. All patients diagnosed with stage IIIA NSCLC between May 2012 and January 2016 in a Victorian Tertiary Referral Centre were included. Guideline concordant initial treatment (GCIT) was defined according to contemporaneous National Comprehensive Cancer Network (NCCN) recommendations based on tumour resectability. Curative intent treatment was defined as surgery and/or definitive chemoradiotherapy delivered with the aim of disease eradication.

Ninety-two patients were included. The mean age of diagnosis was 66 years, and 76.7% had an Eastern Cooperative Oncology Group performance status of 0-1. Curative-intent treatment was delivered in 67.4% of patients, and 62.5% were deemed to have resectable disease of which 58.7% proceeded to surgery. The predominant pre-treatment histological diagnosis was adenocarcinoma (48.3%). Non-operative treatment modalities included platinum-based chemotherapy (64.1%) and radiation (49.4%). One-year survival was 70.5%, while the 5-year survival was significantly lower at 22.2%. Overall, a notable proportion of patients (36.0%) were not treated in accordance with the established guidelines.

While most patients received GCIT, a significant proportion of patients received no or less intensive treatment. This deviation primarily arose from factors such as advanced age, comorbidities and respiratory impairment at baseline.