High-Dose Cyclophosphamide for the Treatment of Refractory T-Cell Acute Lymphoblastic Leukemia in ChildrenKobos, Rachel MD; Shukla, Neerav MD; Renaud, Thomas MD; Prockop, Susan E. MD; Boulad, Farid MD; Steinherz, Peter G. MDJournal of Pediatric Hematology/Oncology: July 2014 - Volume 36 - Issue 5 - p e265–e270 doi: 10.1097/MPH.0000000000000080 Online Articles: Original Articles Abstract Author Information Despite an almost 80% overall survival rate in pediatric T-cell acute lymphoblastic leukemia (T-ALL), there is a subset of patients who are refractory to standard chemotherapy regimens and could benefit from novel treatment approaches. Over a 2-year period, we treated 5 pediatric patients with refractory T-ALL, aged 3 to 15 years, with high-dose cyclophosphamide (CY) at a dose of 2100 mg/m2 for 2 consecutive days either alone (n=1) or in combination with other chemotherapy agents (n=4). Four of these 5 patients had a 1.5 log decrease in disease burden. Three of the 5 patients had no evidence of minimal residual disease (MRD) after high-dose CY. One patient developed transient grade 4 transaminitis and 1 patient developed grade 3 typhlitis. All 5 patients ultimately proceeded to hematopoietic stem cell transplant when MRD levels were <0.01%. Pediatric T-ALL patients with persistent MRD after treatment with conventional chemotherapy may respond to CY at escalated dosing. Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, NY The authors declare no conflict of interest. Reprints: Rachel Kobos, MD, Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (e-mail: firstname.lastname@example.org). Received June 14, 2013 Accepted November 12, 2014 Copyright © 2014 Wolters Kluwer Health, Inc. All rights reserved.