Ramon Guardia

Outcome after relapse of acute lymphoblastic leukemia in adult patients included in four consecutive risk-adapted trials by the PETHEMA Study Group.

Background About one half of adults with acute lymphoblastic leukemia are not cured of the disease and ultimately die. The objective of this study was to explore the factors influencing the outcome of adult patients with relapsed acute lymphoblastic leukemia. Design and Methods We analyzed the characteristics, the outcome and the prognostic factors for survival after first relapse in a series of 263 adult patients with acute lymphoblastic leukemia (excluding those with mature B-cell acute lymphoblastic leukemia) prospectively enrolled in four consecutive risk-adapted PETHEMA trials. Results The median overall survival after relapse was 4.5 months (95% CI, 4–5 months) with a 5-year overall survival of 10% (95% CI, 8%–12%); 45% of patients receiving intensive second-line treatment achieved a second complete remission and 22% (95% CI, 14%–30%) of them remained disease free at 5 years. Factors predicting a good outcome after rescue therapy were age less than 30 years (2-year overall survival of 21% versus 10% for those over 30 years old; P<0.022) and a first remission lasting more than 2 years (2-year overall survival of 36% versus 17% among those with a shorter first remission; P<0.001). Patients under 30 years old whose first complete remission lasted longer than 2 years had a 5-year overall survival of 38% (95% CI, 23%–53%) and a 5-year disease-free survival of 53% (95% CI, 34%–72%). Conclusions The prognosis of adult patients with acute lymphoblastic leukemia who relapse is poor. Those aged less than 30 years with a first complete remission lasting longer than 2 years have reasonable possibilities of becoming long-term survivors while patients over this age or those who relapse early cannot be successfully rescued using the therapies currently available.

Favorable outcome of patients with acute myeloid leukemia harboring a low-allelic burden FLT3-ITD mutation and concomitant NPM1 mutation: relevance to post-remission therapy

Risk associated to FLT3 internal tandem duplication (FLT3-ITD) in patients with acute myeloid leukemia (AML) may depend on mutational burden and its interaction with other mutations. We analyzed the effect of FLT3-ITD/FLT3 wild-type (FLT3wt) ratio depending on NPM1 mutation (NPM1mut) in 303 patients with intermediate-risk cytogenetics AML treated with intensive chemotherapy. Among NPM1mut patients, FLT3wt and low ratio (<0.5) subgroups showed similar overall survival, relapse risk, and leukemia-free survival, whereas high ratio (≥0.5) patients had a worse outcome. In NPM1wt AML, FLT3-ITD subgroups showed a comparable outcome, with higher risk of relapse and shortened overall survival than FLT3wt patients. Allogeneic stem cell transplantation in CR1 was associated with a reduced relapse risk in all molecular subgroups with the exception of NPM1mut AML with absent or low ratio FLT3-ITD. In conclusion, effect of FLT3 burden is modulated by NPM1 mutation, especially in patients with a low ratio.

Treatment of High-Risk Philadelphia Chromosome–Negative Acute Lymphoblastic Leukemia in Adolescents and Adults According to Early Cytologic Response and Minimal Residual Disease After Consolidation Assessed by Flow Cytometry: Final Results of the PETHEMA ALL-AR-03 Trial

PURPOSE Minimal residual disease (MRD) is an important prognostic factor in adults with acute lymphoblastic leukemia (ALL) and may be used for treatment decisions. The Programa Español de Tratamientos en Hematología (PETHEMA) ALL-AR-03 trial (Treatment of High Risk Adult Acute Lymphoblastic Leukemia [LAL-AR/2003]) assigned adolescent and adult patients (age 15 to 60 years) with high-risk ALL (HR-ALL) without the Philadelphia (Ph) chromosome to chemotherapy or to allogeneic hematopoietic stem-cell transplantation (allo-HSCT) according to early cytologic response (day 14) and flow-MRD level after consolidation. PATIENTS AND METHODS Patients with good early cytologic response (< 10% blasts in bone marrow at day 14 of induction) and a flow-MRD level less than 5 × 10(-4) at the end of consolidation were assigned to delayed consolidation and maintenance therapy, and allo-HSCT was scheduled in patients with poor early cytologic response or flow-MRD level ≥ 5 × 10(-4). RESULTS Complete remission was attained in 282 (87%) of 326 patients, and 179 (76%) of 236 patients who completed early consolidation were assigned by intention-to treat to receive allo-HSCT (71) or chemotherapy (108). Five-year disease-free survival (DFS) and overall survival (OS) probabilities were 37% and 35% for the whole series, 32% and 37% for patients assigned to allo-HSCT, and 55% and 59% for those assigned to chemotherapy. Multivariable analysis showed poor MRD clearance (≥ 1 × 10(-3) after induction and ≥ 5 × 10(-4) after early consolidation) as the only prognostic factor for DFS and OS. CONCLUSION Prognosis for Ph-negative HR-ALL in adolescents and adults with good early response to induction and low flow-MRD levels after consolidation is quite favorable when allo-HSCT is avoided. In this study, the pattern of MRD clearance was the only prognostic factor for DFS and OS.

Acute myeloid leukemia with MLL rearrangements: clinicobiological features, prognostic impact and value of flow cytometry in the detection of residual leukemic cells.

The MLL gene, located at 11q23 band, is frequently disrupted by different chromosomal rearrangements that occur in a variety of hematological malignancies. MLL rearrangements are associated with distinct clinical features and a poor prognosis. The aim of this study was to analyze the incidence and the prognostic significance of MLL rearrangements in a consecutive series of adult AML patients and to determine the immunophenotypic features of these cases. The identification of abnormal immunophenotypes could be used for the detection of minimal residual disease (MRD). Ninety-three adult patients with de novo acute myeloid leukemia (AML) were analyzed by Southern blot in order to detect MLL rearrangements (MLL+). RT-PCR and genomic long-range PCR were performed to further characterize MLL partial tandem duplication (PTD) in those patients in whom conventional karyotype did not show 11q23 chromosomal translocations. All the patients were homogeneously immunophenotyped at diagnosis. MLL rearrangements were detected in 13 (14%) patients. Four patients (5%) showed 11q23 translocations by karyotypic conventional analysis. Nine patients (10%) revealed PTD of MLL and one patient showed a MLL cleavage pattern. The MLL+ patients usually expressed myeloid and monocytic antigens CD33 (12/13 cases), CD13 (9/13), CD117 (9/13), CD64 (11/13) and in some cases CD14 (4/11). HLA-DR was also positive in (12/13). Eight out of 13 cases expressed the stem cell marker CD34. Only one patient revealed lymphoid marker reactivity (CD7) and CD56 was expressed in 5/13 cases. All the MLL+ patients showed at least one aberrant phenotype at diagnosis, which allowed us to set out a simple panel for the MRD studies. Twenty-seven samples from eight patients in morphologic complete remission (CR) were analyzed using the aberrant immunologic combinations detected at diagnosis. Phenotypically abnormal cells were detected in all the patients who subsequently relapsed, whereas only one patient with MRD+ remained in CR. Owing to the high level of residual leukemic cells, the MLL+ patients showed a short CR duration and a poor survival. In conclusion, immunophenotyping may be a suitable approach to investigating MRD status in AML patients with PTD of the MLL gene.

Efficacy and safety of rituximab in adult patients with idiopathic relapsing or refractory thrombotic thrombocytopenic purpura: Results of a Spanish multicenter study

BACKGROUND Between 30% and 60% of patients with thrombotic thrombocytopenic purpura (TTP) relapse and mortality remains at 15-20%. Limited clinical data suggest that the administration of anti-CD20 antibody (rituximab) may be useful in preventing acute refractory and chronic relapsing TTP. DESIGN AND METHODS We studied the clinical response to rituximab in 24 adult patients (median age 42 years, range 24-72 years) from 15 Spanish centers with an acute refractory (14 patients) or acute relapsing (10 patients) episode of idiopathic TTP. On admission, every patient received daily plasma exchange (PE). Rituximab was administered at a dose of 375 mg/m(2) weekly for a median of 13 days (range 0-57 days) after starting PE for a median of 4 doses (range 1-8 doses). RESULTS No severe acute or delayed toxicity was observed in the patients treated with rituximab. Three (12.5%) patients died because of TTP-related causes. The remaining 21 (87.5%) patients achieved complete remission in a median of 21 days (range 2-35 days) after initiating rituximab. After a median follow-up of 30 months (range 7.5-74 months), 18 patients are in remission and 3 patients have relapsed at 7, 29, and 29 months. CONCLUSIONS Rituximab appears to be a safe, effective therapy and has a high response rate for the treatment of acute refractory or relapsing idiopathic TTP in adult patients.

CTLA-4 genotype and relapse incidence in patients with acute myeloid leukemia in first complete remission after induction chemotherapy

The recently described single-nucleotide polymorphism CT60, located in the 3′-untranslated region of the CTLA4 (cytotoxic T-lymphocyte antigen 4 ) gene, has been associated with susceptibility to several autoimmune diseases and has also been shown to be involved in immune responses following allogeneic stem cell transplantation (SCT). However, the contribution of the CTLA4 genotype to the control of minimal residual disease in patients with acute myeloid leukemia (AML) has yet to be explored. We investigated the association between the CTLA4 CT60 A/G genotype and the incidence of leukemic relapse in 143 adult patients with AML in first complete remission after the same chemotherapy protocol (CETLAM LAM’03). The CT60 AA genotype was associated with a higher rate of leukemic relapse (56.4 vs 35.6%, P=0.004; hazard ratio (HR)=2.64, 95% confidence interval (CI)=1.36–5.14) and lower overall survival at 3 years (39.4 vs 68.4%, P=0.004; HR=2.80, 95% CI=1.39–5.64). This is the first study to report an association between polymorphisms at CTLA-4 and AML relapse.

Predictive factors for poor peripheral blood stem cell mobilization and peak CD34+cell count to guide pre-emptive or immediate rescue mobilization

BACKGROUND AIMS Failure in mobilization of peripheral blood (PB) stem cells is a frequent reason for not performing hematopoietic stem cell transplantation (HSCT). Early identification of poor mobilizers could avoid repeated attempts at mobilization, with the administration of pre-emptive rescue mobilization. METHODS Data from the first mobilization schedule of 397 patients referred consecutively for autologous HSCT between 2000 and 2010 were collected. Poor mobilization was defined as the collection of < 2 × 10(6) CD34(+)cells/kg body weight (BW). RESULTS The median age was 53 years (range 4-70) and 228 (57%) were males. Diagnoses were multiple myeloma in 133 cases, non-Hodgkins lymphoma in 114, acute myeloid leukemia or myelodysplastic syndrome in 81, Hodgkins lymphoma in 42, solid tumors in 17 and acute lymphoblastic leukemia in 10. The mobilization regimen consisted of recombinant human granulocyte-colony-stimulating factor (G-CSF) in 346 patients (87%) and chemotherapy followed by G-CSF (C + G-CSF) in 51 (13%). Poor mobilization occurred in 105 patients (29%), without differences according to mobilization schedule. Diagnosis, previous therapy with purine analogs and three or more previous chemotherapy lines were predictive factors for poor mobilization. A CD34(+)cell count in PB > 13.8/μL was enough to ensure ≥ 2 × 10(6) CD34(+)cells/kg, with high sensitivity (90%) and specificity (91%). CONCLUSIONS The prevalence of poor mobilization was high, being associated with disease type, therapy with purine analogs and multiple chemotherapy regimens. The threshold of CD34(+) cell count in PB identified poor mobilizers, in whom the administration of immediate or pre-emptive plerixafor could be useful to avoid a second mobilization.

Immunophenotype of acute myeloid leukemia with NPM mutations: Prognostic impact of the leukemic compartment size

NPM mutations are the most common genetic abnormalities found in non-promyelocytic AML. NPM-positive patients usually show a normal karyotype, a peculiar morphologic appearance with frequent monocytic traits and good prognosis in the absence of an associated FLT3 mutation. This report describes the immunophenotypic and genetic characteristics of a consecutive series of NPM-mutated de novo AML patients enroled in the CETLAM trial. Eighty-three patients were included in the study. Complete immunophenotype was obtained using multiparametric flow cytometry. Associated genetic lesions (FLT3, MLL, CEBPA and WT1 mutations) were studied by standardized methods. Real-time PCR was employed to assess the minimal residual status. The most common pattern was CD34-CD15+ and HLA-DR+. Small CD34 populations with immunophenotypic aberrations (CD15 and CD19 coexpression, abnormal SSC) were detected even in CD34 negative samples. Nearly all cases expressed CD33 (strong positivity), CD13 and CD117, and all were CD123+. The stem cell marker CD110 was also positive in most cases. Biologic parameters such as a high percentage of intermediate CD45+ (blast gate) (>75% nucleated cells), CD123+ and FLT3-ITD mutations were associated with a poor outcome. Quantitative PCR positivity had no prognostic impact either after induction or at the end of chemotherapy. Only PCR positivity (greater than 10 copies) detected in patients in haematological remission was associated with an increased relapse rate. Further studies are required to determine whether the degree of leukemic stem cell expansion (CD45+CD123+cells) increases the risk of acquisition of FLT3-ITD and/or provides selective advantages.

Prognostic significance of copy number alterations in adolescent and adult patients with precursor B acute lymphoblastic leukemia enrolled in PETHEMA protocols

Some copy number alterations (CNAs) have independent prognostic significance for adults with acute lymphoblastic leukemia (ALL).

Donor CTLA-4 genotype influences clinical outcome after T cell-depleted allogeneic hematopoietic stem cell transplantation from HLA-identical sibling donors.

CTLA-4 (cytotoxic T-lymphocyte antigen-4) plays a pivotal role in inhibiting T cell activation through competitive interaction with B7 molecules and interruption of costimulatory signals mediated by CD28. Polymorphisms on the CTLA-4 gene have been previously associated with autoimmune diseases, predisposition to leukemic relapse, and with graft-versus-host disease (GVHD) or relapse after allogeneic transplant. As CTLA-4 is expressed on T-lymphocytes, the aim of this study was to determine whether the donor CTLA-4 CT60 genotype also influences clinical outcome even after T cell depletion with CD34-positive selection. We studied 136 patient-donor pairs. Overall survival (OS) was worse for those patients who received grafts from a donor with the CT60 AA genotype rather than from a donor with the AG or GG genotype (35.6% vs 49.4%; P = .043). This association was confirmed through multivariate analysis, which identified the donor CT60 genotype as an independent risk factor for OS (P = .008; hazard ratio [HR]: 2.24, 95% confidence interval [CI]: 1.23-4.08). The donor CT60 AA genotype was also associated with lower disease-free survival, this being related to an increased risk of relapse (P = .001; HR: 3.41, 95% CI: 1.67-6.96) and a trend toward higher transplant-related mortality. These associations were stronger when considering only patients in the early stage of disease. Our results suggest that graft-versus-leukemia (GVL) activity after T cell depletion is conditioned by the donor CTLA-4 genotype.