Survival for colon adenocarcinoma in a hospital-based cancer registry in Cali, Colombia.

Abstract

e15687 Background: Survival estimations for colon adenocarcinoma (CA) have changed in recent decades due to screening strategies and advances in treatment. Cancer estimates are often derived from population-based cancer registries, which lack valuable information, such as clinical stage, to guide decision-making. This study describes the overall survival for CA using a hospital-based cancer registry database. Methods: A retrospective cohort study was conducted using data of patients diagnosed with CA at Fundación Valle del Lili (FVL) between 2015 and 2022, obtained from the hospital’s cancer registry. All CA types were included, while patients under 18 years of age, those with multiple primary tumors, or in situ clinical stage were excluded. Additional data were collected directly from clinical records, pathology reports, and the clinical laboratory. Cases were classified as analytical or non-analytical. All cases were staged using the AJCC 8th edition. The Kaplan-Meier method was used to estimate survival curves. Cox proportional hazards model identified risk factors with adjusted hazard ratios (HR) with 95% confidence intervals. Results: A total of 1,744 patients were identified, of whom 1,643 met the eligibility criteria (237 cases were excluded). The median age was 64 years (IQR: 54–73 years), and 55.1% were female. Analytical cases accounted for 48.5% (n = 796). A 90.1% were treated in the private health insurance system, while 9.9% were treated in the public health insurance system. Clinical staging showed that 11.3% of cases were localized, 55.5% were locally advanced, 20.5% were metastatic, and 12.7% had an unknown stage. Tumor location was predominantly in the left colon (54.7%) compared with the right colon (38.5%), while 6.9% did not have a specific location. The liver was the most common site of metastasis (10.5%). The five-year observed survival was 65.6% (95% CI: 62.8–68.2), regardless of sex, health insurance system, or tumor location. The risk of death was associated with clinical stage—locally advanced (HR: 1.56, 95% CI: 1.05–2.37) or metastatic (HR: 11.18, 95% CI: 7.44–16.80)—and age ≥70 years (HR: 2.36, 95% CI: 1.80–3.08). Conclusions: Patients with CA are often diagnosed at advanced clinical stages, emphasizing the need to implement screening programs to detect the disease at earlier stages in our context.