The TAB-EOAO study: Trends in use and benefit of adjuvant chemotherapy between early onset and average onset locally advanced colon cancer.

• DOI: 10.1200/jco.2025.43.4_suppl.105
• Publication Date: 2025-01-27T14:32:44Z
• Authors: Carolina Bernabe; Dennis Orkoulas R...; Jee-Young Moon; Chenxin Zhang; Jihoon John Choi; Bahar Laderian; Fernand Bteich; Chaoyuan Kuang; Yvonne M. Saenger; Andreas Kaubisch; Jesus Del Santo A...
• Keywords: Adjuvant Chemotherapy

105 Background: Despite the declining incidence rates (IR) in average onset colon cancer (AO-CC), IR for early (EO-CC), defined as patients (pts) younger than 50-years-old at diagnosis, has been increasing. Treatment high risk locally advanced (CC) is surgical resection followed by adjuvant chemotherapy (AC). Data indicates a more permissive use EO-CC. There limited data about treatment and survival trends Thus, we aimed to assess benefit of AC between EO vs AO CC disease. Methods: diagnosed 2000-2020 were identified Surveillance, Epidemiology, End Results Program (SEER) Database. Eligible pts adults (≥18), Stage II or III diagnosis. disease was further stratified low (pT1-3) (pT4). Logistic regression methods used Odds Ratio (OR) EO-CC AO-CC; Cox models compare overall (OS) Cancer-specific (CSS) both groups during 2000-2010 2011-2020. Results: Our study included 136,676 (AO-CC= 121,606; =15,070). The median age 44 years versus 71 AO-CC population. increased over time (63% 66%) (33% 40%). Moreover, with received less entire (see table). In AO-CC, improved CSS (HR=0.69 2000-2010, HR=0.50 2011-2020). However, among those EO-CC, 2011-2020 (HR=0.76) but did not improve (HR=1.02). Conclusions: Over past 20 managed aggressively, especially stage where current guidelines do support AC. this real world set show that decade 2000- 2010 2011- 2020 period. Further analysis may clarify specific benefits clearly remains need better stratification, including ctDNA, identify subpopulations will best from Multivariable logistic model timeframe interaction term: Age* stage. OR 95% CI 0.23 (0.21, 0.26) 0.28 (0.24, 0.32) (0.22, 0.36) 0.36 (0.32, 0.4) 0.30 (0.26, 0.34)