Early-onset gastrointestinal cancers: Racial disparities in stage and survival from large-scale community oncology data.

1653 Background: Research on early-onset (EO) gastrointestinal (GI) cancers has focused predominantly on colorectal cancer, leaving knowledge gaps regarding racial variations across other GI malignancies. We used real-world data from a large, nationally representative community oncology network to assess age-of-onset differences in clinical characteristics and survival for colorectal, gastric, and esophageal cancers across key social determinants. Methods: This was a retrospective cohort of patients with colorectal, gastric and esophageal cancers treated within the U.S. Oncology Network and non-Network practices from 2000–2025. Patients were categorized as EO (<50 years) or average-onset (AO) (≥50 years) at diagnosis. Characteristics including demographics, stage at diagnosis (I–II, III–IV, or unknown), and distress level (NCCN Distress Thermometer) were sourced from iKnowMed. Overall survival (OS) was assessed from diagnosis using Kaplan–Meier methods, stratified by race/ethnicity and stage. Results: Among 195,624 patients with GI cancers, 23,244 (11.9%) had EO disease. In the EO cohort, 20,203 (87%) had colorectal, 1,693 (7%) gastric, and 1,348 (6%) esophageal cancers. EO disease occurred in a more racially and ethnically diverse population, with higher representation of Hispanic/Latino (10.3% vs 6.7%), Black (8.2% vs 6.6%), and Indigenous/Native (1.3% vs 0.8%) patients, and higher female representation (46.4% vs 43.9%), versus AO disease. Advanced-stage (III–IV) disease at diagnosis was more common in EO vs AO disease across colorectal (41% vs 32%), esophageal (41% vs 31%), and gastric (37% vs 29%) cancers. Among EO patients, stage III/IV disease at diagnosis was higher in Black (75.3%) and Asian (73.1%) versus White patients (64.9%), whereas among AO patients advanced stage was more balanced across racial groups (66.2%, 64.9%, 62.9%, respectively). Within EO advanced-stage disease, median OS was 8.1 m shorter in Black vs White patients (51.0 vs 59.1 m), compared with only a 1.6 m difference in AO disease (35.0 vs 36.6 m). Among patients with available distress data (N=3,426), distress was higher in EO versus AO patients (median 4 vs 3) but did not differ by race, sex or ethnicity. Conclusions: This study represents one of the largest real-world characterizations of EO GI cancers, revealing that EO patients more often present with advanced-stage and higher distress than AO counterparts. While racial disparities in stage were relatively balanced in AO disease, they were exacerbated in EO disease, with Black and Asian patients presenting with substantially higher rates of advanced disease. The resulting survival gap between Black and White EO patients underscores a widening disparity less pronounced in older patients. A precision–public health approach is needed to address biological and socioeconomic drivers of outcomes in young, diverse GI cancer populations.