Eulàlia Genescà

Feasibility and results of subtype-oriented protocols in older adults and fit elderly patients with acute lymphoblastic leukemia: Results of three prospective parallel trials from the PETHEMA group.

BACKGROUND AND OBJECTIVE The prognosis of acute lymphoblastic leukemia (ALL) is poor in older adults and elderly patients, and subtype-oriented prospective trials are scarce in these patients. We present the results of three prospective parallel subtype-oriented protocols in fit patients older than 55 years. PATIENTS AND METHODS In 2008, three prospective phase II trials in patients older than 55 years were activated: ALLOLD07 for Philadephia (Ph) chromosome-negative ALL, ALLOPH07 for Ph-positive ALL, and BURKIMAB08 for mature B-ALL. Early death (ED), complete remission (CR), disease-free survival (DFS), overall survival (OS) and toxicity were analyzed. RESULTS 56, 53 and 21 patients from the ALLOLD07, ALLOPH07 and BURKIMAB08 trials, respectively, were evaluable. CR was 74%, 87% and 70%, with an ED rate of 13%, 11% and 15%, respectively. The medians of DFS were 8 and 38 months for ALLOLD07 and ALLOPH07 protocols, not being achieved in the BURKIMAB08 trial (p=0.001), and the median OS was 12, 37 and 25 months, respectively (p=0.030). Neutropenia, thrombocytopenia and infections were less frequent in the ALLOPH07 trial vs. ALLOLD07 and BURKIMAB trials, and renal toxicity and mucositis were more frequent in the BURKIMAB08 trial vs. the ALLOLD07 and ALLOPH07 trials. ECOG score and WBC count had prognostic significance for OS in ALLOPH07 and BURKIMAB08 trials, whereas no prognostic factors were identified in ALLOLD07 protocol. CONCLUSION Subtype-oriented treatment had an impact in the outcome of older adults with ALL. The poorest outcome was observed in Ph-negative non-Mature B-cell ALL patients, for whom improvements in therapy are clearly needed.

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).

Profile of blinatumomab and its potential in the treatment of relapsed/refractory acute lymphoblastic leukemia

The CD19 marker is expressed on the surface of normal and malignant immature or mature B-cells. On the other hand, immunotherapy involving T-cells is a promising modality of treatment for many neoplastic diseases including leukemias and lymphomas. The CD19/CD3-bispecific T-cell-engaging (BiTE®) monoclonal antibody blinatumomab can transiently engage cytotoxic T-cells to CD19+ target B-cells inducing serial perforin-mediated lysis. In the first clinical trial, blinatumomab showed efficacy in non-Hodgkin’s lymphomas, but the most important trials have been conducted in relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) and in ALL with minimal residual disease. Encouraging reports on the activity of blinatumomab in R/R Philadelphia chromosome-negative B-cell precursor ALL led to its approval by the US Food and Drug Administration on December 3, 2014 after an accelerated review process. This review focuses on the profile of blinatumomab and its activity in R/R ALL.

Implications of basic research in clinical practice: toward a personalizedmedicine in T-cell Acute Lymphoblastic Leukemia (T-ALL)

Acute Lymphoblastic Leukemia (ALL) is the most common cancer in children and one of the main causes of death among childhood blood disorders. There are two subtypes according to the affected lymphoid progenitor: B-ALL and T-ALL. The T-ALL is the less common and historically was associated with poor prognosis in both adults and children, although at present, treatment outcomes do not differ significantly between the two types of ALL. The T-ALL subtype is the most complex and heterogeneous at the genetic level and currently the one with less new therapeutic alternatives available. This trend is changing thanks to the remarkable progress that is being made in understanding the biology involved. Advances in genomic research during last decade have largely contributed to this progress. Moreover many efforts are being made to identify which of this new basic data is relevant for clinical practice. This will allow us to better define the risk and take decisions on the best treatment to apply to each patient. Therefore we are moving towards a personalized patient management that ultimately will result in an increase in survival and progress to T-ALL cure. This review summarizes the most relevant and applicable biological findings in T-ALL made in recent years and their therapeutic implications that will influence the clinical practice in the future.

Copy number profiling of adult relapsed B‐cell precursor acute lymphoblastic leukemia reveals potential leukemia progression mechanisms

The outcome of relapsed adult acute lymphoblastic leukemia (ALL) remains dismal despite new therapeutic approaches. Previous studies analyzing relapse samples have shown a high degree of heterogeneity regarding gene alterations without an evident relapse signature. Bone marrow or peripheral blood samples from 31 adult B‐cell precursor ALL patients at first relapse, and 21 paired diagnostic samples were analyzed by multiplex ligation probe‐dependent amplification (MLPA). Nineteen paired diagnostic and relapse samples of these 21 patients were also analyzed by SNP arrays. A trend to acquire homozygous CDKN2A/B deletions and a significant increase in the number of copy number alterations (CNA) was observed from diagnosis to first relapse. Evolution from an ancestral clone was the main pattern of clonal evolution. Relapse samples were extremely heterogeneous regarding CNA frequencies. However, CDKN2A/B, PAX5, ETV6, ATM, IKZF1, VPREB1, and TP53 deletions and duplications of 1q, 8q, 17q, 21, X/Y PAR1, and Xp were frequently detected at relapse. Duplications of genes involved in cell proliferation, drug resistance and stem cell homeostasis regulation, as well as deletions of KDM6A and STAG2 genes emerged as specific alterations at relapse. Genomics of relapsed adult B‐cell precursor ALL is highly heterogeneous, although some recurrent lesions involved in essential pathways deregulation were frequently observed. Selective and simultaneous targeting of these deregulated pathways may improve the results of current salvage therapies.

Comparison of intensive, pediatric-inspired therapy with non-intensive therapy in older adults aged 55–65 years with Philadelphia chromosome-negative acute lymphoblastic leukemia

BACKGROUND AND OBJECTIVE The standardization of treatment of older adults with Philadelphia chromosome negative (Ph-) acute lymphoblastic leukemia (ALL) is challenging, especially in the age range of 55-65 years. This study aimed to compare intensive, pediatric-inspired therapy with non-intensive therapy in this population of patients. PATIENTS AND METHODS The outcomes of 67 patients prospectively included in two consecutive pediatric-inspired intensive protocols (ALL-HR03 and ALL-HR11) from the Spanish PETHEMA Group were compared with those from 44 patients included in a contemporary semi-intensive protocol (ALL-OLD07). RESULTS Baseline patient and ALL characteristics were similar in both groups, except for a younger median age in the intensive group (medians: 58 vs. 62 years). Patients treated intensively had a higher complete remission rate (85% vs. 64%, p = 0.005), a lower cumulative incidence of relapse (39% [95%CI, 25% to 52%] vs. 60% [95%CI, 38% to 77%], p = .003), a similar cumulative incidence of treatment-related mortality (28% [95% CI, 18%, 40%] vs. 21% [95% CI, 10%, 34%]) and superior event-free survival at 2 years (37% [95%CI, 25%-49%) vs. 21% [8%-34%], p = 0.002). On multivariable analysis the type of protocol was the only variable with independent significance for event-free survival (HR [95% CI]: 2 [1.3, 3], p = .002). CONCLUSIONS Compared with less intensive chemotherapy, pediatric-inspired intensive chemotherapy significantly improves the outcome of older adults with Ph-negative ALL in the age range of 55-65 years.

Frequency and clinical impact of CDKN2A/ARF/CDKN2B gene deletions as assessed by in-depth genetic analyses in adult T cell acute lymphoblastic leukemia

Recurrent deletions of the CDKN2A/ARF/CDKN2B genes encoded at chromosome 9p21 have been described in both pediatric and adult acute lymphoblastic leukemia (ALL), but their prognostic value remains controversial, with limited data on adult T-ALL. Here, we investigated the presence of homozygous and heterozygous deletions of the CDKN2A/ARF and CDKN2B genes in 64 adult T-ALL patients enrolled in two consecutive trials from the Spanish PETHEMA group. Alterations in CDKN2A/ARF/CDKN2B were detected in 35/64 patients (55%). Most of them consisted of 9p21 losses involving homozygous deletions of the CDKNA/ARF gene (26/64), as confirmed by single nucleotide polymorphism (SNP) arrays and interphase fluorescence in situ hybridization (iFISH). Deletions involving the CDKN2A/ARF/CDKN2B locus correlated with a higher frequency of cortical T cell phenotype and a better clearance of minimal residual disease (MRD) after induction therapy. Moreover, the combination of an altered copy-number-value (CNV) involving the CDKN2A/ARF/CDKN2B gene locus and undetectable MRD (≤ 0.01%) values allowed the identification of a subset of T-ALL with better overall survival in the absence of hematopoietic stem cell transplantation.

Increased Survival due to Lower Toxicity for High Risk T-cell Acute Lymphoblastic Leukemia Patients in 2 consecutive Pediatric-Inspired PETHEMA Trials

Pediatric‐inspired regimens have been adopted by several groups as the treatment strategy for adult patients with acute lymphoblastic leukemia (ALL). Whether subsequent modifications of these protocols have led to an improvement in the outcome of patients is uncertain, especially in T‐cell ALL. We analyzed 169 patients with high‐risk T‐cell ALL included in two consecutive trials of the PETHEMA Group (HR‐ALL03 [n = 104] and the more contemporary HR‐ALL11 [n = 65]).

Alteraciones en el número de copias en pacientes adultos con leucemia linfoblástica aguda B madura, tratados con inmunoquimioterapia específica

BACKGROUND AND OBJECTIVE Unlike Burkitt lymphoma, molecular abnormalities other than C-MYC rearrangements have scarcely been studied in patients with mature B acute lymphoblastic leukemia (B-ALL). The aim of this study was to analyze the frequency and prognostic significance of copy number alterations (CNA) in genes involved in lymphoid differentiation, cell cycle and tumor suppression in adult patients with B-ALL. PATIENTS AND METHODS We have analyzed by multiplex ligation-dependent probe amplification the genetic material from bone marrow at diagnosis from 25 adult B-ALL patients treated with rituximab and specific chemotherapy. RESULTS The most frequent CNA were alterations in the 14q32.33 region (11 cases, 44%) followed by alterations in the cell cycle regulator genes CDKN2A/B and RB1 (16%). No correlation between the presence of specific CNA and the clinical-biologic features or the response to therapy was found. CONCLUSIONS The high frequency of CNA in the 14q32.33 region, CDKN2A/B and RB1 found in our study could contribute to the aggressiveness and invasiveness of mature B-ALL.