Outcomes of patients with oesophageal and gastric cancer in relation to their age and metropolitan residential status: A South Australian audit.

Abstract

e16095 Background: The incidence of oesophago-gastric cancer (OG) is increasing in the younger population. Factors such as obesity, chronic gastroesophageal reflux disease, smoking or a low dietary intake of fruits and vegetables may be responsible. Inferior survival outcomes are observed in younger patients with OG cancer. Survival rates can differ by geographic location, with poorer outcomes seen in remote and non-metropolitan regions. Aim To evaluate patient characteristics and outcomes of patients with gastro-oesophageal cancers in younger (<50 years) when compared to older (>50 years) patients and those residing in rural versus metropolitan areas in South Australia. Methods: Data from a tertiary referral hospital database in South Australia was retrospectively collected between 2012 to 2022. All patients with OG cancers were included. Baseline characteristics including demographics, risk factors for OG cancer, type and stages of disease, geographic location were collected. Survival outcomes of gastro oesophageal cancer patients <50 years and >50 years of age as well as those living in metropolitan versus rural locations were analysed. Statistical analyses were done using Pearson’s Chi square test, Wilcoxon rank sum test, Fisher exact tests and multivariate models. Results: Of the 937 patients in this audit, 6.5%% (n=61) were < 50 years of age, 72% men (n=670), median age of diagnosis was 72 years. There was statistically significant difference in the proportion of patients with different anatomical types of OG cancer based on age <50 versus >50 (P=0.02), while there was no difference in other baseline characteristics. Within the group of OG cancer patients <50 years, the frequency of gastric adenocarcinoma was more, when compared to older, >50 year group (55.7% vs 31.3%) whilst other cancer types such as GOJ adenocarcinoma (1.6% vs 6.3%), oesophageal squamous (8.2% vs 14.8%) and adenocarcinoma (34.4% vs 47.6%) were found less frequent in <50 year group compared to >50 year group. There were no significant differences observed in the 3 year (P=0.49), 5 year (P=0.61) and overall survival (2.29 vs 1.78 years, P=0.63) rates, in OG cancer patients < 50 years vs > 50 years old. Among 874 OG cancer patients with data available on geographic location, there was no significant differences observed between 3-year (P = 0.25), 5-year (P =0.27) or overall survival (1.72 vs 1.61 years, P = 0.3) in metropolitan versus rural patients in South Australia. Conclusions: In this audit gastric adenocarcinoma was more common in younger patients (<50 years of age). Young-onset OG cancer patients, when defined as aged younger than 50 years, had equivalent survival compared with their older counterparts and there were no significant differences seen in overall survival rates based on their geographic locations.