Evaluation of 243 Patients with Myelodysplastic Syndrome (MDS) Referred for Hematopoietic Cell Transplant (HCT) Including Donor Availability and HCT Outcomes.

Abstract 3383

Poster Board III-271

Allogeneic hematopoietic cell transplantation (HCT) remains the only curative treatment strategy for patients (pts) with MDS. Until recently, the toxicity of HCT excluded older pts such as those with MDS from HCT. In July 2004 the Moffitt Cancer Center (MCC) implemented a pharmacokinetically targeted IV busulfan plus fludarabine (tBuFlu) induction regimen that was myeloablative, with reduced treatment related toxicity, permitting the expansion of empiric age limitations for HCT up to 75 years (yrs). From that time until August 2009, 243 new pts (NP) with a diagnosis of MDS or CMML were evaluated for HCT. An allogeneic donor was identified in 170 pts and 112 received an HCT at MCC, the majority using tBuFlu. (HCT) The median age of the 112 transplant pts at Moffitt was 55.6 yrs (24.8 – 73.5). Sixty pts were older than 55 yrs and 11 were above 65 years of age. All pts that proceeded to transplant had adverse risk factors including progression to AML (25), secondary MDS (30) or progression of disease. At the NP visit, IPSS risk was Low (11), Int-1 (35), Int-2 (42), and High (21) or not evaluable (3) (NE). Donors included 49 sibling donors (SIB), 48 matched unrelated donors (MUD) and 15 mismatched unrelated donors (mMUD). Median time from the NP visit to donor cell infusion was 197 days (98-1810) for mMUD; 132 days (64 – 488) for MUD and 119 days (25 – 613) for SIB. Median follow-up is 19.3 months (0 – 61.4) and the Kaplan-Meier overall survival (OS) from NP visit is 77 % at one year and 56 % at two years. Overall survival is not statistically different between SIB, MUD or mMUD HCT (P=0.39). In 58 pts who did not receive a HCT, a donor was identified. (Yes donor, No HCT) Median age was 57 yrs (19 – 69) with 28 pts older than 55yrs and 9 pts older than 65 yrs. At the NP visit, IPSS was Low (5), Int-1 (19), Int-2 (17), High (16) and NE (1). Ten had treatment related disease and 26 had progressed to AML. Donors included SIB (14), MUD (27), mMUD (15), and umbilical cord blood (2). Median follow up is 10.3 months (1.7 – 66.3). Reasons for not proceeding to HCT following the donor search included waiting for progression due to low risk disease or good response to therapy (9), progression of disease or death with ongoing donor search (21), new ineligibility for HCT (12), pt declined HCT (8), HCT elsewhere (3) and 5 pts are in active evaluation to proceed to HCT. Seventy-three pts did not obtain a donor (No Donor, No HCT). Median age was 64.4 yrs (32.6 – 72.1) with 65 pts older than 55yrs and 31 older than 65 yrs. IPSS at NP visit was Low (8), Int-1 (16), Int-2 (25), High (16) and NE (8). Twenty had treatment related disease and 18 had progressed to AML. The reasons for not proceeding to transplant were as follows; ineligibility for HCT or progressed/died during the donor search (27), insurance denial (15), patient declined HCT (10), low risk disease (5), no suitable donor found (9), and 7 are in active searches. Median follow up of these pts is 6.7 months (0.9 – 61.3). For the entire cohort (243 pts), pts with a donor had significantly improved overall survival vs pts with no donor (P=0.003); there was no difference in OS between pts with a donor who did not proceed to HCT and everyone without a donor (P=0.27). Twenty-eight of the 73 pts without a donor did not have donor searches due to ineligibility for HCT at NP visit, pt declined at NP visit or insurance declined even though the pt was eligible. If these are excluded, in the remaining 215pts OS for pts with an identified donor was improved compared to OS of those without a donor (P=0.009) and pts with a donor and no HCT had similar OS to those without an identified donor (P=0.3). These data demonstrate that 70% of patients can acquire a suitable allogeneic donor and 47% of patients seen as a HCT new patient consult can proceed to HCT for MDS with a significant overall survival advantage using a SIB, MUD or mMUD.