Jennifer R. Brown, Wael Saber, Edwin Alyea, Ronald Sobecks, Uday Popat, Usama Gergis, Asad Bashey, Richard F. Olsson, Saurabh Chhabra, Taiga Nishihori, Baldeep M. Wirk, Jean Yared, Michael R. Grunwald, Jan Cerny, Bipin N. Savani, Amer Beitinjaneh, Sunita Nathan, Edward A. Copelan, Nakhle Saba, Tamila Kindwall-Keller, Attaphol Pawarode, Brian T. Hill, Harry C. Schouten, Mahmoud Aljurf, Ayman Saad, Nilanjan Ghosh, Mohamed A. Kharfan-Dabaja, Melhem Solh, Jean-Yves Cahn, Yoshihiro Inamoto, Gerhard C. Hildebrandt, Ran Reshef, Hillard Lazarus, Ulrike Bacher, Sid Ganguly, Mehdi Hamadani, David I. Marks, Robert Peter Gale, Gregory A. Hale, Minoo Battiwalla, Miguel-Angel Perales, Sergio A. Giralt, Amelia Langston, Stephen Forman, Joseph McGuirk, Jayesh Mehta, Richard Nash, Edward Agura, Joseph Uberti, Steven Devine, Robert Negrin, William Hogan, Joseph Pidala, Oliver Press, Mazyar Shadman, Mohamed L. Sorror, Joseph H. Antin, Virginia O. Volpe, Matthew S. Davids, Zhen-Huan Hu, Kwang Woo Ahn, and Haesook T. Kim
Purpose:To develop a prognostic model and cytogenetic risk classification for previously treated patients with chronic lymphocytic leukemia (CLL) undergoing reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT).Experimental Design:We performed a retrospective analysis of outcomes of 606 patients with CLL who underwent RIC allogeneic HCT between 2008 and 2014 reported to the Center for International Blood and Marrow Transplant Research.Results:On the basis of multivariable models, disease status, comorbidity index, lymphocyte count, and white blood cell count at HCT were selected for the development of prognostic model. Using the prognostic score, we stratified patients into low-, intermediate-, high-, and very-high-risk [4-year progression-free survival (PFS) 58%, 42%, 33%, and 25%, respectively, P < 0.0001; 4-year overall survival (OS) 70%, 57%, 54%, and 38%, respectively, P < 0.0001]. We also evaluated karyotypic abnormalities together with del(17p) and found that del(17p) or ≥5 abnormalities showed inferior PFS. Using a multivariable model, we classified cytogenetic risk into low, intermediate, and high (P < 0.0001). When the prognostic score and cytogenetic risk were combined, patients with low prognostic score and low cytogenetic risk had prolonged PFS (61% at 4 years) and OS (75% at 4 years).Conclusions:In this large cohort of patients with previously treated CLL who underwent RIC HCT, we developed a robust prognostic scoring system of HCT outcomes and a novel cytogenetic-based risk stratification system. These prognostic models can be used for counseling patients, comparing data across studies, and providing a benchmark for future interventions. For future study, we will further validate these models for patients receiving targeted therapies prior to HCT.