In-Vivo Purging with Rituximab (R) Followed By Z/BEAM Vs BEAM/R Autologous Stem Cell Conditioning for Relapsed Diffuse Large B-Cell Lymphoma (DLBCL) Patients (pts): Mature Results from a Combined Analysis of 3 Trials

• Published in: Blood 2015-12, Vol.126 (23), p.3192-3192
• Main Authors: Khouri, Issa F., Sui, Dawen, Turturro, Francesco, Erwin, William D, Bassett, Roland L, Korbling, Martin, Valverde, Rosamar, Ahmed, Sairah, Alousi, Amin M., Anderlini, Paolo, Bashir, Qaiser, Ciurea, Stefan O., Oran, Betul, Olson, Amanda, Popat, Uday R., Patel, Krina K, Qazilbash, Muzaffar H., Fanale, Michelle A., Fayad, Luis E., Nastoupil, Loretta, Westin, Jason R, Gulbis, Alison M, Medeiros, L. Jeffrey, Young, Ken H., Jessop, Aaron
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V126.23.3192.3192

Background: The addition of R has been shown to improve results for pts with relapsed DLBCL who undergo BEAM (carmustine, etoposide, cytarabine, melphalan) high-dose chemotherapy followed by an autologous stem cell transplantation (ASCT) (Khouri IF, J Clin Oncol 2005;23;2240). The incorporation of radiolabeled antibodies such as yttrium-90 ibritumomab tiuxetan to conditioning regimens has also been evaluated without additional toxicity (Khouri IF, ASH 2007, abstract 620). Subsequently, a randomized trial which was undertaken at our center to compare these 2 regimens was closed early because of slow accrual. Herein, we compare the long-term outcome in pts treated in these trials. Methods: A combined analysis was carried out from 113 pts. Between 1999 and 2003, 57 pts with relapsed DLBCL were enrolled on a protocol with BEAM conditioning plus R at 1000 mg/m2 on days +1 and +8 after ASCT (Group A). Between 2004 and 2006, a similar group of 26 patients were entered onto a trial consisting of ibritumomab tiuxetan plus BEAM (Z/BEAM). Ibritumomab tiuxetan was given at the fixed doseof 0.4 mCi/Kg on day -21 followed by BEAM(days -7 to -1) (Group B). In 2007-2010, a randomized trial was undertaken comparing BEAM/R (Group C, n=16) and Z/BEAM (Group D, n=14). All pts received R during stem cell collection, administered at 375 mg/m2 on the day before initiating chemotherapy for stem cell mobilization, and again at 1000 mg/m2, 7 days later. The same eligibility criteria were used for all groups. In addition, pts who were enrolled on the randomized trial (Groups C and D) underwent FISH analysis for -5 and -7 and cytogenetic analysis by G-banding pre-enrollment; those who had a clonal abnormality were excluded. We also retrospectively evaluated the histologic subtypes of mediastinal, transformed and de novo DLBCL. We determined the cell-of-origin of the latter using the Visco/Young and Choi W, et al. immunohistochemical algorithms. A univariate analysis was conducted for factors of interest: this included the group conditioning, age, sex, number of prior treatments, disease status at transplantation (CR/PR), IPI (0 vs >0), LDH, β2-microglobulin, PET status, and histology subtype. Multivariate survival analysis was then conducted using backward elimination on the basis of the likelihood ratio test and including the conditioning regimens and all the factors with P < 0.05 in the univariate analyses. Patients: There was no significant difference in the prognostic factors des