David Martínez-Cuadrón

Pharmacological Profiles of Acute Myeloid Leukemia Treatments in Patient Samples by Automated Flow Cytometry: A Bridge to Individualized Medicine

BACKGROUND We have evaluated the ex vivo pharmacology of single drugs and drug combinations in malignant cells of bone marrow samples from 125 patients with acute myeloid leukemia using a novel automated flow cytometry-based platform (ExviTech). We have improved previous ex vivo drug testing with 4 innovations: identifying individual leukemic cells, using intact whole blood during the incubation, using an automated platform that escalates reliably data, and performing analyses pharmacodynamic population models. PATIENTS AND METHODS Samples were sent from 24 hospitals to a central laboratory and incubated for 48 hours in whole blood, after which drug activity was measured in terms of depletion of leukemic cells. RESULTS The sensitivity of single drugs is assessed for standard efficacy (EMAX) and potency (EC50) variables, ranked as percentiles within the population. The sensitivity of drug-combination treatments is assessed for the synergism achieved in each patient sample. We found a large variability among patient samples in the dose-response curves to a single drug or combination treatment. CONCLUSION We hypothesize that the use of the individual patient ex vivo pharmacological profiles may help to guide a personalized treatment selection.

Central nervous system involvement at first relapse in patients with acute myeloid leukemia

The risk factors for and incidence of central nervous system involvement at first relapse in adult patients with acute myeloid leukemia have not been established. This single-center study analyzed the prognostic factors for and cumulative incidence of meningeal relapse in 458 adult patients achieving complete remission. Before 1990, patients received old chemotherapy approaches without stem cell transplantation that often included prophylactic intrathecal chemotherapy. Since 1990, modern protocols included stem cell transplantation without intrathecal prophylaxis. Meningeal relapse occurred in 6 patients (overall 5-year cumulative incidence 1.3%). The 5-year cumulative incidence of meningeal relapse in patients treated with old and modern protocols were 3.9% and 0.3%, respectively. Univariate and multivariate analyses showed that the chemotherapy approach was the main prognostic factor for central nervous system relapse (P=0.02). This study shows an extremely low incidence of meningeal relapse in adult patients with acute myeloid leukemia treated with modern protocols including stem cell transplantation without intrathecal prophylaxis.

A scoring system to predict the risk of death during induction with anthracycline plus cytarabine‐based chemotherapy in patients with de novo acute myeloid leukemia

A prognostic index to predict induction death in adult patients receiving induction chemotherapy for de novo acute myeloid leukemia (AML) was developed.

Incidence and risk factors of post-engraftment invasive fungal disease in adult allogeneic hematopoietic stem cell transplant recipients receiving oral azoles prophylaxis

Studies that analyze the epidemiology and risk factors for invasive fungal disease (IFD) after engraftment in alloSCT are few in number. This single-center retrospective study included 404 alloSCT adult recipients surviving >40 days who engrafted and were discharged without prior IFD. All patients who received ⩾20 mg/day of prednisone were assigned to primary oral prophylaxis (itraconazole or low-dose voriconazole). The primary end point was the cumulative incidence (CI) of probable/proven IFD using the European Organization for Research and Treatment of Cancer and Mycoses Study Group (EORTC/MSG) criteria. The independent prognostic factors after multivariate analyses were used to construct a post-engraftment IFD risk score. The 1-year CI of IFD was 11%. The non-relapse mortality was 40% in those developing IFD and 16% in those who did not. The intent-to-treat analysis showed that 17% of patients abandoned the assigned prophylaxis. Age >40 years, ⩾1 previous SCT, pre-engraftment neutropenia >15 days, extensive chronic GVHD and CMV reactivation were independent risk factors. The post-engraftment IFD score stratified patients into low risk (0–1 factor, CI 0.7%), intermediate risk (2 factors, CI 9.9%) and high risk (3–5 factors, CI 24.7%) (P<0.0001). The antifungal prophylaxis strategy failed to prevent post-engraftment IFD in 11% of alloSCT. Our risk score could be useful to implement risk-adapted strategies using antifungal prophylaxis after engraftment.

Effect of CD8+ Cell Content on Umbilical Cord Blood Transplantation in Adults with Hematological Malignancies

Total nucleated (TNCs) and CD34(+) cells are considered major determinants of outcome after umbilical cord blood (UCB) transplantation but the effect of other cell subtypes present in the graft is unknown. This single-center cohort study included patients with hematological malignancies who received UCB transplantation after a myeloablative conditioning regimen. UCB units were primarily selected according to cell content, both TNCs and CD34(+) cells, and also according to the degree of HLA matching. Counts of several cell subtypes of the infused UCB unit, together with HLA disparities and other patient- and transplantation-related characteristics, were analyzed by multivariable methodology for their association with myeloid and platelet engraftment, graft-versus-host disease, nonrelapse mortality (NRM), disease-free survival (DFS), and overall survival (OS). Two hundred patients (median age, 32 years) were included in the study. In multivariable analyses, a greater number of CD8(+) cells was significantly associated with better results for myeloid (P = .001) and platelet (P = .008) engraftment, NRM (P = .02), DFS (P = .007), and OS (P = .01). CD34(+) cell content was predictive of myeloid engraftment (P < .001). This study suggests that the outcome after UCB transplantation in adults with hematological malignancies could be better when UCB grafts had a greater CD8(+) cell content.

A prognostic model for survival after salvage treatment with FLAG-Ida +/− gemtuzumab-ozogamicine in adult patients with refractory/relapsed acute myeloid leukaemia

The combination of fludarabine, cytarabine, idarubicin, and granulocyte colony‐stimulating factor (FLAG‐Ida) is widely used in relapsed/refractory acute myeloid leukaemia (AML). We retrospectively analysed the results of 259 adult AML patients treated as first salvage with FLAG‐Ida or FLAG‐Ida plus Gentuzumab‐Ozogamicin (FLAGO‐Ida) of the Programa Español de Tratamientos en Hematología (PETHEMA) database, developing a prognostic score system of survival in this setting (SALFLAGE score). Overall, 221 patients received FLAG‐Ida and 38 FLAGO‐Ida; 92 were older than 60 years. The complete remission (CR)/CR with incomplete blood count recovery (CRi) rate was 51%, with 9% of induction deaths. Three covariates were associated with lower CR/CRi: high‐risk cytogenetics and t(8;21) at diagnosis, no previous allogeneic stem cell transplantation (allo‐SCT) and relapse‐free interval <1 year. Allo‐SCT was performed in second CR in 60 patients (23%). The median overall survival (OS) of the entire cohort was 0·7 years, with 22% OS at 5‐years. Four independent variables were used to construct the score: cytogenetics, FLT3‐internal tandem duplication, length of relapse‐free interval and previous allo‐SCT. Using this stratification system, three groups were defined: favourable (26% of patients), intermediate (29%) and poor‐risk (45%), with an expected 5‐year OS of 52%, 26% and 7%, respectively. The SALFLAGE score discriminated a subset of patients with an acceptable long‐term outcome using FLAG‐Ida/FLAGO‐Ida regimen. The results of this retrospective analysis should be validated in independent external cohorts.

Rapid Screening of ASXL1, IDH1, IDH2, and c-CBL Mutations in de Novo Acute Myeloid Leukemia by High-Resolution Melting

Recently, many novel molecular abnormalities were found to be distinctly associated with acute myeloid leukemia (AML). However, their clinical relevance and prognostic implications are not well established. We developed a new combination of high-resolution melting assays on a LightCycler 480 and direct sequencing to detect somatic mutations of ASXL1 (exon 12), IDH1 (exon 4), IDH2 (exon 4), and c-CBL (exons 8 and 9) genes to know their incidence and prognostic effect in a cohort of 175 patients with de novo AML: 16 patients (9%) carried ASXL1 mutations, 16 patients had IDH variations (3% with IDH1(R132) and 6% with IDH2(R140)), and none had c-CBL mutations. Patients with ASXL1 mutations did not harbor IDH1, [corrected] or CEBPA mutations, and a combination of ASXL1 and IDH2 mutations was found only in one patient. In addition, we did not find IDH1 and FLT3 or CEBPA mutations concurrently or IDH2 with CEBPA. IDH1 and IDH2 mutations were mutually exclusive. Alternatively, NPM1 mutations were concurrently found with ASXL1, IDH1, or IDH2 with a variable incidence. Mutations were not significantly correlated with any of the clinical and biological features studied. High-resolution melting is a reliable, rapid, and efficient screening technique for mutation detection in AML. The incidence for the studied genes was in the range of those previously reported. We were unable to find an effect on the outcome.

WT1 isoform expression pattern in acute myeloid leukemia

WT1 plays a dual role in leukemia development, probably due to an imbalance in the expression of the 4 main WT1 isoforms. We quantify their expression and evaluate them in a series of AML patients. Our data showed a predominant expression of isoform D in AML, although in a lower quantity than in normal CD34+ cells. We found a positive correlation between the total WT1 expression and A, B and C isoforms. The overexpression of WT1 in AML might be due to a relative increase in A, B and C isoforms, together with a relative decrease in isoform D expression.

Influence of cytarabine metabolic pathway polymorphisms in acute myeloid leukemia induction treatment

Abstract Cytarabine is considered the most effective chemotherapeutic option in acute myeloid leukemia (AML). The impact of 10 polymorphisms in cytarabine metabolic pathway genes were evaluated in 225 adult de novo AML patients. Variant alleles of DCK rs2306744 and CDA rs602950 showed higher complete remission (p = .024, p = .045), with lower survival rates for variant alleles of CDA rs2072671 (p = .015, p = .045, p = .032), rs3215400 (p = .033) and wild-type genotype of rs602950 (p = .039, .014). Induction death (p = .033) and lower survival rates (p = .021, p = .047) were correlated to RRM1 rs9937 variant allele. In addition, variant alleles of CDA rs532545 and rs602950 were related to skin toxicity (p = .031, p = .049) and mucositis to DCK rs2306744 minor allele (p = .046). Other toxicities associated to variant alleles were hepatotoxicity to NT5C2 rs11598702 (p = .032), lung toxicity (p = .031) and thrombocytopenia to DCK rs4694362 (p = .046). This study supports the interest of cytarabine pathway polymorphisms regarding efficacy and toxicity of AML therapy in a coherent integrated manner.

Impact of ABC single nucleotide polymorphisms upon the efficacy and toxicity of induction chemotherapy in acute myeloid leukemia

Abstract Anthracycline uptake could be affected by efflux pumps of the ABC family. The influence of 7 SNPs of ABC genes was evaluated in 225 adult de novo acute myeloid leukemia (AML) patients. After multivariate logistic regression there were no significant differences in complete remission, though induction death was associated to ABCB1 triple variant haplotype (p = .020). The ABCB1 triple variant haplotype was related to higher nephrotoxicity (p = .016), as well as this haplotype and the variant allele of ABCB1 rs1128503, rs2032582 to hepatotoxicity (p = .001; p = .049; p < .001). Furthermore, the variant allele of ABCC1 rs4148350 was related to severe hepatotoxicity (p = .044), and the variant allele of ABCG2 rs2231142 was associated to greater cardiac (p = .004) and lung toxicities (p = .038). Delayed time to neutropenia recovery was observed with ABCB1 rs2032582 variant (p = .047). This study shows the impact of ABC polymorphisms in AML chemotherapy safety. Further prospective studies with larger population are needed to validate these associations.