Gastrointestinal involvement refines prognosis in minnesota standard risk acute graft-vs.-host disease.

Minnesota acute graft versus host disease (AGVHD) risk score is a validated tool to stratify newly-diagnosed patients into standard-risk (SR) and high-risk (HR) groups with ~85% having SR AGVHD. We aimed to identify factors for further risk-stratification within Minnesota SR patients. A single-center, retrospective analysis of consecutive patients between 1/2010 and 12/2014 was performed. Patients who developed AGVHD within 100 days and treated with systemic corticosteroids were included (N = 416), 356 (86%) of which were Minnesota SR and 60 (14%) had HR AGVHD. Isolated upper gastrointestinal (GI) AGVHD patients had significantly better day 28 and 56 CR/PR rates (90% vs. 72%, p = 0.004) and (83% vs 66%, p = 0.01), respectively, and lower 1-year non-relapse mortality (NRM; 10% vs. 22%; HR 0.4, p = 0.03). Lower GI AGVHD had less favorable outcomes with 1-year NRM of 40% (HR 2.1, p = 0.001), although CR/PR rates were not statistically different. In multivariate analysis, lower GI involvement (HR 2.6, p < 0.001), age ≥ 50 (HR 2.9, p < 0.001) and HCT-CI > 3 (HR 2.1, p = 0.002) predicted for 1-year NRM. Heterogeneity within Minnesota SR patients requires consideration in clinical trials, as distinct outcomes are observed in those with isolated upper GI and lower GI AGVHD, highlighting the importance of stratification in clinical trial design.