Survival predictors in early onset stage IV colorectal mucinous adenocarcinoma: A Surveillance, Epidemiology, and End Results-based analysis.

Abstract

Early onset colorectal cancer and mucinous adenocarcinoma histology in young patients is an challenging scenario, made more unfortunate due to absence of specific guidelines. Accordingly, we aimed to assess cancer-specific survival (CSS) and identify survival predictors in patients aged ≤50 with stage IV mucinous adenocarcinoma. Retrospective cohort analysis using Surveillance, Epidemiology, and End Results data (2000-2022) identified patients ≤50 years with stage IV colorectal cancer mucinous adenocarcinoma. Multivariable Cox regression and Kaplan-Meier analyses assessed CSS and identified independent predictors. Median survival of 1,542 patients was 18 months; 5-year CSS was 14.3%. Metatstatic lung disease was associated with significantly reduced 5-year CSS (13.9% vs 17.4%; P < .001); distant metastasectomy was associated with significantly higher 5-year CSS (20.3% vs 12.1%; P < .001). Neoadjuvant and adjuvant systemic therapy was associated with significantly higher 5-year CSS than adjuvant therapy alone (18.5%) and similar 5-year CSS to neoadjuvant therapy alone (cancer-specific survival: 28.9% vs 27.1%). Independent predictors of reduced cancer-specific survival included household income <$50,000 (hazard ratio, 2.70; 95% confidence interval, 1.20-6.06) and $50,000-$74,999 (hazard ratio, 2.08; 95% confidence interval, 1.05-4.10), a greater number of positive lymph nodes (hazard ratio, 1.02; 95% confidence interval, 1.01-1.04), and the presence of lung metastases (hazard ratio, 1.93; 95% confidence interval, 1.22-3.04). Conversely, distant metastasectomy (hazard ratio, 0.71; 95% confidence interval, 0.53-0.97), neoadjuvant systemic therapy (hazard ratio, 0.41; 95% confidence interval, 0.18-0.92), and combined neoadjuvant and adjuvant systemic therapy (hazard ratio, 0.42; 95% confidence interval, 0.20-0.90) were independently associated with improved cancer-specific survival. Stage IV early onset mucinous adenocarcinoma presents with advanced disease and poor outcomes. Socioeconomic factors and metastatic burden significantly influence survival. Systemic therapy and distant metastasectomy offer the most significant survival benefits.