Remission Status and Performance Status, but Not Cytogenetic Risk Group, Are Associated with Outcome After Reduced Intensity Conditioning (RIC) and Allogeneic Hematopoietic Cell Transplantation (HCT) for Therapy-Related Myeloid Neoplasms (t-MN): Results of the University of Chicago Experience.
Authors: Kenkre Vaishalee P. , Horowitz Sarah , Larson Richard A. , Artz Andrew , Rich Elizabeth Shima , Zhang Yanming , Le Beau Michelle M. , Godley Lucy A , Odenike Olatoyosi , Thirman Michael , van Besien Koen , Stock Wendy 
Published: October 2019

Abstract
Abstract 3395
Poster Board III-283
Therapy-related myeloid neoplasms (t-MN) are associated with unfavorable cytogenetics, drug resistance, and poor outcomes. For appropriate candidates, allogeneic HCT is the most likely curative therapy. We, and others, have shown that outcomes from HCT using RIC regimens are comparable to standard myeloablative conditioning regimens for high-risk patients with myeloid neoplasms. Few studies have focused on transplant outcomes for pts with t-MN. Therefore, we reviewed outcomes of 46 pts (median age 51; range, 25-71) with t-MN who underwent HCT at the University of Chicago between 3/89 and 1/09. Eleven had presented with < 20% marrow blasts, and 35 had > 20% blasts. Prior malignancies included Hodgkin lymphoma (n = 9), NHL (n = 9), CLL (n = 2), ALL (n = 2), APL (n = 1), and solid tumors (n = 19). Four pts had non-malignant prior diseases (SLE, Crohns disease, heart transplant, kidney transplant), but had received cytotoxic therapy. Since 2001, 37 pts received RIC transplants, whereas 9 earlier pts received myeloablative conditioning. Overall survival (OS) at day 100, 1 yr, and 2 yrs was 63% (95%CI, 49-77%), 40% (95%CI, 25-55%), and 34% (95%CI, 19-49%), respectively. Disease status at transplant was highly predictive of outcome (p = 0.03), with those pts in CR (n = 12) at the time of transplant exhibiting a 2 yr OS of 69% (95% CI, 38-100%) versus those with persistent disease (n = 34) exhibiting a 2 yr OS of 24% (95% CI, 8-40) (see figure below). ECOG performance status (PS) of 0 and 1 (n = 32) had similar outcomes, while no pts with a PS of 2 (n= 4) were alive at 2 years. Neither patient age (>50) nor donor source (related [n = 28] vs unrelated [n = 18]) had a significant impact on outcome (p= 0.73 and 0.07, respectively). Interestingly, cytogenetic subset did not affect outcome; 2 yr OS was 35% (95%CI, 9-61%) for those with intermediate (n = 15) and 31% (95%CI, 12-50%) for those with poor-risk (n = 30) cytogenetics. Only one patient in the group had a good-risk cytogenetic pattern. RIC was associated with a 2 yr OS of 38% (95%CI, 18-58%), while ablative regimens resulted in a 2 yr OS of 21% (95% CI, 0-43%) (p = 0.04). Since RIC transplants were performed more recently, improvements in supportive care may have affected outcomes. These data represent one of the largest series reported on transplant outcome for t-MN. We conclude that RIC followed by related or unrelated donor HCT should be considered for pts with t-MN, regardless of cytogenetic abnormalities. The results for pts transplanted in remission are encouraging with 2 yr OS of 69%.

Disclosures:
No relevant conflicts of interest to declare.