Impact of longitudinal comprehensive distress screening on cancer-related distress and overall survival.

831 Background: Diagnosis and first-course treatment of gastrointestinal malignancies pose multifactorial and evolving stressors, causing cancer-related distress with implications for treatment tolerance, adherence, and oncologic outcomes. Comprehensive longitudinal distress screening data in this population have not previously been reported; the natural history of distress and its association with overall survival (OS) is poorly characterized. Methods: Patients undergoing first-course treatment for gastrointestinal malignancies from 2019-2024 at our institution were longitudinally screened with a hybrid online/in-clinic approach. Fifteen unique domains of cancer-related distress were evaluated (no, mild, moderate, severe). The presence of multi-domain distress (moderate/severe distress in ≥5 domains) was evaluated with logistic regression; OS was assessed with Simon-Makuch Kaplan-Meier analysis and discrete-time survival models. Results: 2253 patients (n=10,926 screens) were identified ); screening response rate was 99.2%. The most common primary sites were pancreatic (27.7%), colonic (18.4%), rectal (11.4%), gastric (10.1%), small intestinal (9.9%) and hepatobiliary (8.1%). 819 (36.3%) patients developed multi-domain (≥5 domain) distress, most commonly at first screening (n=537, 65.6%); fatigue (76.6%), pain/numbness (73.1%), spouse/family concerns (69.0%), work/home life disruptions (67.4%), and anxiety (63.2%) were most common. On multivariable logistic regression, male sex (OR 0.61, P