Treatment patterns and survival outcomes in colon cancer patients with autism spectrum disorder: A propensity score–matched retrospective multicenter cohort study.

e15729 Background: Patients with autism spectrum disorder (ASD) face documented barriers to cancer care, yet oncologic outcomes in this population remain understudied. We investigated treatment patterns and survival outcomes comparing patients with ASD versus those without ASD with colon cancer. Methods: Using the TriNetX network, we identified adults with colon cancer diagnosed from 2015 to 2025. Patients with ASD (n = 368) were propensity score–matched 1:1 to non-ASD controls on demographics, comorbidities, and tumor characteristics (stage, mutations, etc.). Primary outcomes included receipt of any therapy and NCCN-concordant systemic therapy, hospitalization resource utilization, adverse events, and all-cause mortality across multiple time windows (3 months, 6 months, 1 year, 3 years, and any time). A prespecified subgroup analysis examined stage IV patients (n = 94 per arm) and stage I–III patients (n = 274 per arm). Measures of association (RR) and time-to-event hazard ratios (HRs) were evaluated. Results: Cohorts were well-balanced (SMD < 0.1). In the full cohort (N = 368/368), ASD patients received significantly less systemic therapy (chemotherapy/biologics/immunotherapy) at 3 months (13.3% vs 19.3%; RR 0.69, p = 0.028; HR 0.65, p = 0.018), 3 years (28.5% vs 35.9%; RR 0.80, p = 0.033; HR 0.74, p = 0.023), and any time (30.7% vs 38.6%; RR 0.80, p = 0.025; HR 0.73, p = 0.014); receipt of any therapy also trended lower at 3 months (19.6% vs 25.0%; RR 0.78, p = 0.075; HR 0.74, p = 0.051). ASD was associated with fewer ED visits at 6 months (16.0% vs 21.2%; HR 0.71, p = 0.046) and lower sepsis at 3 months (2.7% vs 5.7%; RR 0.48, p = 0.043; HR 0.46, p = 0.039). Despite these treatment differences, there were no significant differences in palliative care, bowel complications, or all-cause mortality in the full cohort (any-time mortality: 22.6% vs 23.4%, p = 0.79). In prespecified subgroup analyses, stage I–III patients had comparable colectomy rates. In contrast, excess mortality was concentrated in stage IV ASD patients: mortality was higher at 1 year (28.7% vs 14.9%; RR 1.93, p = 0.022; HR 1.98, p = 0.034), 3 years (45.7% vs 27.7%; RR 1.65, p = 0.010; HR 1.58, p = 0.064), and any time (47.9% vs 33.0%; RR 1.45, p = 0.038; HR 1.41, p = 0.037), with a concomitant trend toward lower systemic therapy at 3 months (12.8% vs 22.3%; RR 0.57, p = 0.091). Conclusions: In a propensity-matched real-world cohort, adults with ASD and colon cancer were less likely to receive NCCN-concordant systemic therapy. While overall outcomes were similar in the full cohort, stage IV ASD patients experienced markedly higher mortality - highlighting ASD as a high-risk equity population and an urgent target for autism-informed pathways to ensure timely, guideline-based treatment.