Real-world experience of immune checkpoint inhibitors in patients with solid tumours in the Top End of the Northern Territory, Australia from 2016 to 2021: a retrospective observational cohort study.

BACKGROUND: Use of immune checkpoint inhibitors is growing, but clinical trial data may not apply to Indigenous patients or patients living in remote areas. AIMS: To provide real-world incidence of immune-related adverse events (irAE) in the Top End of the Northern Territory and compare incidence between demographic subgroups. METHODS: This retrospective, observational, cohort study collected data from electronic records of patients living in the Top End with solid organ cancer treated with immunotherapy between January 2016 and December 2021. The primary outcome was cumulative incidence of any-grade and severe irAE. Secondary outcomes were overall survival, treatment duration and reason for treatment discontinuation. RESULTS: Two hundred and twenty-six patients received immunotherapy. Forty-eight (21%) lived in a remote or very remote area, and 36 (16%) were Indigenous. Cumulative incidence of any-grade irAE was 54% (122/226 patients); incidence of severe irAE was 26% (59/226 patients). Rates were similar between Indigenous and non-Indigenous patients of any-grade (42% vs 56%, P = 0.11) and severe (11% vs 18%, P = 0.29) irAE. However, Indigenous patients had shorter treatment duration, more frequently discontinued treatment due to patient preference and appeared to have shorter median overall survival than non-Indigenous patients (17.1 vs 30.4 months; hazard ratio (HR) = 1.5, 95% confidence interval (CI) = 0.92-2.66). There was no difference in mortality between remote and urban patients (median overall survival 27.5 vs 30.2 months; HR = 1.1, 95% CI = 0.7-1.7). CONCLUSIONS: Rates of irAE in our cohort are comparable to those in the published literature. There was no significant difference in any-grade or severe irAE incidence observed between Indigenous and non-Indigenous patients.

Significance of lung nodules detected on chest CT among adult Aboriginal Australians - a retrospective descriptive study.

INTRODUCTION: There are limited data on chest computed tomography (CT) findings in the assessment of lung nodules among adult Aboriginal Australians. In this retrospective study, we assessed lung nodules among a group of adult Aboriginal Australians in the Northern Territory of Australia. METHODS: Patients who underwent at least two chest CT scans between 2012 and 2020 among those referred to undergo lung function testing (spirometry) were included. Chest CT scans were assessed for the number, location, size and morphological characteristics of lung nodules. RESULTS: Of the 402 chest CTs assessed, 75 patients (18.7%) had lung nodules, and 57 patients were included in the final analysis with at least two CT scans available for assessment over a median follow-up of 87 weeks. Most patients (68%) were women, with a median age of 58 years and smoking history in 83%. The majority recorded only a single nodule 43 (74%). Six patients (10%) were diagnosed with malignancy, five with primary lung cancer and one with metastatic thyroid cancer. Of the 51 (90%) patients assessed to be benign, 64 nodules were identified, of which 25 (39%) resolved, 38 (59%) remained stable and one (1.8%) enlarged on follow-up. Nodules among patients with malignancy were typically initially larger and enlarged over time, had spiculated margins and were solid, showing no specific lobar predilection. CONCLUSIONS: Most lung nodules in Aboriginal Australians are likely to be benign. However, a proportion could be malignant. Further prospective studies are required for prognostication and monitoring of lung nodules in this population.