166 Evaluating Donor Lymphocyte Infusions (DLI) for the Treatment of Falling Chimerism, Minimal Residual Disease and Relapse After Pediatric Hematopoietic Stem Cell Transplantation (HSCT)

Track: Contributed Abstracts
Wednesday, February 13, 2013, 6:45 PM-7:45 PM
Hall 1 (Salt Palace Convention Center)
Javier Amin El-Bietar, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Caridad Martinez, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Catherine M. Bollard, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Swati Naik , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Kathryn Leung, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Stephen Gottschalk, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Nabil Ahmed, MD , Center for Cell and Gene Therapy-Dept of Pediatrics Hem/Onc, Baylor College of Medicine, Houston, TX
Carl Allen, MD, PhD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Helen E Heslop, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Malcolm K. Brenner, MD, PhD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
Robert A. Krance, MD , Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
We conducted an eleven-year retrospective review (2001-2012) of 65 HSCT patients with myeloid malignancies (n= 32), lymphoid malignancies (n=27) or CML (n=6) who received DLI post-transplant to treat mixed chimerism (MC, n=15), minimal residual disease (MRD, n=15) or relapsed disease (RD, n=35). Patients had received transplants from related (n=20) including haploidentical (n=26), unrelated (n=35) or cord blood (n=1) donors. Forty-two patients received total body irradiation (TBI) and cyclophosphamide-based conditioning while 16 received busulfan and cyclophosphamide-based regimens.  Twenty-seven patients received conditioning with other chemotherapies ± TBI.  MC was defined as evidence of recipient cells on whole blood or bone marrow analysis using fluorescence in-situ hybridization (FISH) or short tandem repeats. Nine of the 15 MC patients who received DLI did so after the discontinuation (median of 35 days, range 1-217) of graft versus host disease (GvHD) prophylaxis, while the 6 remaining DLI recipients had not been on prophylactic therapy. MRD was defined as the detection of a clone ≥ 0.01% using polymerase chain reaction or FISH. Relapse was defined as any patient with a ≥ 5% blast population detected in peripheral blood and confirmed by microscopic or flow cytometric analysis. As a group, 26/65 patients are alive after receiving DLI with a median follow-up of 24 months (range 3-102).  Of patients with MC, 9/15 remained in remission for a median of 22 months (range 3-85) with 7/15 experiencing Grade II-IV aGvHD.  Of patients with MRD, 12/15 remained in remission for a median of 77 months (range 5-102) with 5/15 experiencing grade II-IV aGvHD.  Eight of these 12 surviving patients were Philadelphia chromosome-positive.  Of patients with RD, 5/36 remain alive with 3/5 in remission for a median of 43 months (range 4-63).  11/31 patients who expired experienced Grade II-IV aGvHD. Hence, DLI may benefit pediatric myeloid and lymphoid malignancy patients post-HSCT with MC and MRD (especially those with Philadelphia chromosome-positive leukemia). However, DLIs produced remission in only 3/36 patients with RD and the associated risk of significant GvHD likely worsens quality of remaining life in the non-responders.
See more of: Poster Session 1: Clinical Cellular Therapy
See more of: Contributed Abstracts
<< Previous Abstract | Next Abstract >>