Litzow, Mark R.

Abstract T-cell immunophenotype of acute lymphoblastic leukemia (T-ALL) is an uncommon aggressive leukemia that can present with leukemic and/or lymphomatous manifestations. Molecular studies are enhancing our understanding of the pathogenesis of T-ALL, and the discovery of activating mutations of NOTCH1 and FBXW7 in a majority of patients has been a seminal observation. The use of pediatric intensive combination chemotherapy regimens in adolescents and young adults has significantly improved the outcome of patients with T-ALL. The use of nelarabine for relapsed and refractory T-ALL results in responses in a substantial minority of patients. Allogeneic hematopoietic cell transplantation (HCT) still plays a key role in patients with high-risk or relapsed/refractory disease. γ-Secretase inhibitors hold promise for the treatment of patients with NOTCH1 mutations, and the results of clinical trials with these agents are eagerly awaited. It is recommended that younger patients receive a pediatric-intensive regimen. Older and unfit patients can receive suitable multiagent chemotherapy and be allocated to HCT based on their response, risk factors, and comorbidities. Although advances in the treatment of T-ALL have lagged behind those of B-cell ALL, it is hoped that the molecular revolution will enhance our understanding of the pathogenesis and treatment of this aggressive lymphoid malignancy.

The widespread use of complementary and alternative medicine (CAM) in cancer survivors is well known despite a paucity of scientific evidence to support its use. The number of survivors of hematopoietic stem cell transplant (HCT) is growing rapidly and HCT clinicians are aware that many of their patients use CAM therapies consistently. However, due to a paucity of data regarding the benefits and harms of CAM therapies in these survivors, clinicians are reluctant to provide specific recommendations for or against particular CAM therapies. A systematic literature review was conducted with a search using PubMed, the Cochrane Database of Systematic Reviews, and Ovid online for each CAM therapy as defined by the National Center of Complementary and Alternative Medicine. The search generated 462 references, of which 26 articles were deemed to be relevant for the review. Due to extensive heterogeneity in data and limited randomized trials, a meta‐analysis could not be performed but a comprehensive systematic review was conducted with specified outcomes for each CAM therapy. In randomized controlled trials, certain mind and body interventions such as relaxation were observed to be effective in alleviating psychological symptoms in patients undergoing HCT, whereas the majority of the other CAM treatments were found to have mixed results. CAM use is an understudied area in HCT survivorship and clinicians should convey the benefits and uncertainties concerning the role of CAM therapies to their patients. Cancer 2015;121:2303–2313. © 2015 American Cancer Society.

BACKGROUNDPoor marrow cellularity alone cannot explain poor hematopoietic progenitor cell (HPC) mobilization. This study assessed the role of CD8+ T cells in HPC cell mobilization and engraftment.STUDY DESIGN AND METHODSMobilization and engraftment were assessed in 192 autologous HPC donors. CD34+, CD4+, and CD8+ T‐cell contents in apheresis products were evaluated. Using a chemotaxis assay, we assessed the effect of purified autologous CD8+ T cells from low and high mobilizers on HPC migration from high to low stromal cell–derived factor (SDF‐1α) concentration gradients. We also assessed CD8+ T‐cell content association with days to neutrophil engraftment.RESULTSThe median number of CD34+ cells/kg was 4.7 × 106. Patients were categorized according to their total CD34+ cell collection quartile distribution into low, moderate, and high mobilizers. We found that HPC products from low mobilizers contained more CD8+ T cells than HPC products from moderate and high mobilizers. Chemotaxis assays showed depletion of CD8+ T cells enhances HPC mobilization independent of SDF‐1α concentration. Neutrophil engraftment analysis showed that the higher the CD8+ T‐cell content per unit CD34+ cell, the faster the rate of engraftment.CONCLUSIONOur findings suggest CD8+ T cells inhibit HPC mobilization and facilitate homing and engraftment.

AbstractBackgroundVoriconazole is a commonly used antifungal medication in allogeneic hematopoietic stem cell transplantation (allo‐HSCT) patients. In solid organ transplantation, voriconazole use has been associated with the development of cutaneous squamous cell carcinoma (SCC). We sought to determine if voriconazole use was associated with SCC in patients undergoing allo‐HSCT.MethodsWe retrospectively reviewed consecutive adult patients who underwent allo‐HSCT at Mayo Clinic from January 2007 through July 2012. Multivariable Cox models were created to assess the relationship of SCC with two time‐dependent voriconazole exposure variables: (i) history of voriconazole exposure (yes/no), and (ii) cumulative days of voriconazole use.ResultsIn our cohort of 381 allo‐HSCT patients, SCC developed in 26 of 312 patients exposed to voriconazole (25 post‐voriconazole) and in 1 of 69 patients who received alternative antifungal agent(s). Cumulative incidence of SCC was estimated to be 19% at 5 years post allo‐transplant. Cumulative days of voriconazole use was found to be a risk factor for SCC, and this relationship persisted in a multivariable model using previously identified risk factors as covariates (hazard ratio 1.859 for each 180 days of use, P < 0.001).ConclusionThis is the first study, to our knowledge, to identify cumulative days of voriconazole use as a risk factor for SCC development following allo‐HSCT, and may help guide appropriate antifungal use in this patient population.

SummaryMomelotinib (a JAK1 and JAK2 inhibitor) induces both anaemia and spleen responses in myelofibrosis (MF). Momelotinib treatment‐emergent peripheral neuropathy (TE‐PN) was documented in 44 (44%) of 100 MF patients treated at our institution; median time of TE‐PN onset was 32 weeks and duration 11 months. Improvement after drug dose reduction or discontinuation was documented in only two patients. TE‐PN was significantly associated with treatment response (P = 0·02) and longer survival (P = 0·048) but significance was lost during multivariate analysis that included treatment duration. TE‐PN did not correlate with initial or maximum momelotinib dose or previous treatment with JAK inhibitor or thalidomide.

Abstract Many tumors are believed to be maintained by a small number of cancer stem–like cells, where cure is thought to require eradication of this cell population. In this study, we investigated the dynamics of acute promyelocytic leukemia (APL) before and during therapy with regard to disease initiation, progression, and therapeutic response. This investigation used a mathematical model of hematopoiesis and a dataset derived from the North American Intergroup Study INT0129. The known phenotypic constraints of APL could be explained by a combination of differentiation blockade of PML–RARα–positive cells and suppression of normal hematopoiesis. All-trans retinoic acid (ATRA) neutralizes the differentiation block and decreases the proliferation rate of leukemic stem cells in vivo. Prolonged ATRA treatment after chemotherapy can cure patients with APL by eliminating the stem-like cell population over the course of approximately one year. To our knowledge, this study offers the first estimate of the average duration of therapy that is required to eliminate stem-like cancer cells from a human tumor, with the potential for the refinement of treatment strategies to better manage human malignancy. Cancer Res; 74(19); 5386–96. ©2014 AACR.