Category: Acute Lymphoblastic Leukemia Meeting: 2014 SOHO Annual Meeting Citation: Society of Hematologic Oncology, SOHO Annual Meeting Proceedings. Vol 2, No. 1 (Sept 17), 2014:113. Abstract #113 Delays in Intensification are Common in Adults with Acute Lymphoblastic Leukemia (ALL), are Associated with Decreased Survival in Allogeneic Hematopoietic Cell Transplant (HCT) Patients Anita Kumar, MD MS1, Phyllis Gimotty, PhD2, Joel Gelfand, MD MS3, Georgina Buck, MS4, Jacob Rowe, MD5, Anthony Goldstone, MD6, Adele Fielding, MB BS PhD7, David Marks8, Mark Litzow, MD9, Elisabeth Paietta, PhD10, Hillard Lazarus, MD11, Martin Tallman, MD12, Selina Luger, MD13, Alison Loren, MD MS14 1Hematology/Oncology, University of Pennsylvania; 2Perelman School of Medicine at the University of Pennsylvania, University of Pennsylvania; 3Department of Dermatology, University of Pennsylvania; 4Clinical Trial Service Unit; 5Rambam Medical Center; 6North London Cancer Network, University College London Hospital; 7Hematology, University College London; 8University Hospitals NHS foundation trust; 9Mayo Clinic; 10Montefiore Medical Center; 11Case Western Reserve University; 12Leukemia Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center; 13Department of Hematology/Oncology, University of Pennsylvania; 14Department of Hematology/Oncology, University of Pennsylvania Context: ALL has a high relapse rate in adults. While different biology may partly account for poorer survival in comparison to children, adherence to complex chemotherapy regimens may also play a role. Objective: To identify risk factors and outcomes associated with delays during chemotherapy for adults with ALL. Design: We conducted an observational study using data from ECOG 2993/ MRC_UKALLXII. We analyzed Ph- patients who started intensification after documented complete remission (CR). Long delay (LD) was defined as > 98 days from induction start to intensification start (IS), corresponding with >2 weeks delay per protocol. Very Long Delay (VLD) was defined as a >4 weeks delay. Results: 1247 patients met inclusion criteria. Female sex (p<0.001), Black race (p=0.01), and older age (p<0.001) were associated with increased LD. During induction, infection (p=0.01), dose reductions (p=0.001), neutropenia duration (p=0.007), thrombocytopenia (p<0.001), and hospitalization (p<0.001) were Table 1. associated with LD. Table I shows multivariate analysis risk factors. 687/1247 (55%) patients died, with median time to death from IS of 13.3 months (0.8-231). Myeloablative allogeneic HCT (allo HCT) patients had poorer overall survival from start of intensification (OS-IS) and event free survival (EFS-IS) after VLD (p=0.02, p=0.03). Survival was not worse for non-transplant patients after VLD (p=0.24, p=0.10). In a multivariate Cox regression, allo HCT patients with a VLD had significantly worse OS-IS (HR 1.4, p=0.02) and EFS-IS (HR 1.4, p=0.02). There was no difference in OS or EFS in patients who received non-transplant post-remission therapy based on delay. Conclusion: In a comprehensive analysis of the largest adult ALL study reported, we identified risk factors predictive of LD and VLD. Our findings highlighted that delays were associated with chemotherapy toxicity and healthcare disparities. Further studies will prospectively identify patient barriers to on-schedule treatment with a goal of improved adherence and long-term survival.