Renato Bassan

Modern Therapy of Acute Lymphoblastic Leukemia

Although acute lymphoblastic leukemia is curable in one third of adult patients, results vary greatly on account of different clinical, immunologic, and cytogenetic/genetic characteristics. These data, along with the kinetics of response to early treatment, help establish the individual risk class with considerable accuracy, and support risk-specific treatments that should warrant optimal results with as little as possible nonrelapse mortality. Modern first-line therapy consists of standard- and high-dose chemotherapy (increasingly inspired to pediatric principles), hematopoietic stem-cell transplantation, and new targeted therapy, all integrated with the analysis of prognostic factors and the study of subclinical residual disease for key therapeutic decisions. These changes are improving long-term outcome, which in ongoing studies is expected close to 50% or greater.

Blinatumomab versus Chemotherapy for Advanced Acute Lymphoblastic Leukemia

Background Blinatumomab, a bispecific monoclonal antibody construct that enables CD3‐positive T cells to recognize and eliminate CD19‐positive acute lymphoblastic leukemia (ALL) blasts, was approved for use in patients with relapsed or refractory B‐cell precursor ALL on the basis of single‐group trials that showed efficacy and manageable toxic effects. Methods In this multi‐institutional phase 3 trial, we randomly assigned adults with heavily pretreated B‐cell precursor ALL, in a 2:1 ratio, to receive either blinatumomab or standard‐of‐care chemotherapy. The primary end point was overall survival. Results Of the 405 patients who were randomly assigned to receive blinatumomab (271 patients) or chemotherapy (134 patients), 376 patients received at least one dose. Overall survival was significantly longer in the blinatumomab group than in the chemotherapy group. The median overall survival was 7.7 months in the blinatumomab group and 4.0 months in the chemotherapy group (hazard ratio for death with blinatumomab vs. chemotherapy, 0.71; 95% confidence interval [CI], 0.55 to 0.93; P=0.01). Remission rates within 12 weeks after treatment initiation were significantly higher in the blinatumomab group than in the chemotherapy group, both with respect to complete remission with full hematologic recovery (34% vs. 16%, P<0.001) and with respect to complete remission with full, partial, or incomplete hematologic recovery (44% vs. 25%, P<0.001). Treatment with blinatumomab resulted in a higher rate of event‐free survival than that with chemotherapy (6‐month estimates, 31% vs. 12%; hazard ratio for an event of relapse after achieving a complete remission with full, partial, or incomplete hematologic recovery, or death, 0.55; 95% CI, 0.43 to 0.71; P<0.001), as well as a longer median duration of remission (7.3 vs. 4.6 months). A total of 24% of the patients in each treatment group underwent allogeneic stem‐cell transplantation. Adverse events of grade 3 or higher were reported in 87% of the patients in the blinatumomab group and in 92% of the patients in the chemotherapy group. Conclusions Treatment with blinatumomab resulted in significantly longer overall survival than chemotherapy among adult patients with relapsed or refractory B‐cell precursor ALL. (Funded by Amgen; TOWER ClinicalTrials.gov number, NCT02013167.)

Chemotherapy-Phased Imatinib Pulses Improve Long-Term Outcome of Adult Patients With Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: Northern Italy Leukemia Group Protocol 09/00

PURPOSE Short imatinib pulses were added to chemotherapy to improve the long-term survival of adult patients with Philadelphia chromosome (Ph) -positive acute lymphoblastic leukemia (ALL), to optimize complete remission (CR) and stem-cell transplantation (SCT) rates. PATIENTS AND METHODS Of 94 total patients (age range, 19 to 66 years), 35 represented the control cohort (ie, imatinib-negative [IM-negative] group), and 59 received imatinib 600 mg/d orally for 7 consecutive days (ie, imatinib-positive [IM-positive] group), starting from day 15 of chemotherapy course 1 and from 3 days before chemotherapy during courses 2 to 8. Patients in CR were eligible for allogeneic SCT or, alternatively, for high-dose therapy with autologous SCT followed by long-term maintenance with intermittent imatinib. RESULTS CR and SCT rates were greater in the IM-positive group (CR: 92% v 80.5%; P = .08; allogeneic SCT: 63% v 39%; P = .041). At a median observation time of 5 years (range, 0.6 to 9.2 years), 22 patients in the IM-positive group versus five patients in the IM-negative group were alive in first CR (P = .037). Patients in the IM-positive group had significantly greater overall and disease-free survival probabilities (overall: 0.38 v 0.23; P = .009; disease free: 0.39 v 0.25; P = .044) and a lower incidence of relapse (P = .005). SCT-related mortality was 28% (ie, 15 of 54 patients), and postgraft survival probability was 0.46 overall. CONCLUSION This imatinib-based protocol improved long-term outcome of adult patients with Ph-positive ALL. With SCT, post-transplantation mortality and relapse remain the major hindrance to additional therapeutic improvement. Additional intensification of imatinib therapy should warrant a better molecular response and clinical outcome, both in patients selected for SCT and in those unable to undergo this procedure.

Whole-exome sequencing identifies somatic mutations of BCOR in acute myeloid leukemia with normal karyotype.

Among acute myeloid leukemia (AML) patients with a normal karyotype (CN-AML), NPM1 and CEBPA mutations define World Health Organization 2008 provisional entities accounting for approximately 60% of patients, but the remaining 40% are molecularly poorly characterized. Using whole-exome sequencing of one CN-AML patient lacking mutations in NPM1, CEBPA, FLT3-ITD, IDH1, and MLL-PTD, we newly identified a clonal somatic mutation in BCOR (BCL6 corepressor), a gene located on chromosome Xp11.4. Further analyses of 553 AML patients showed that BCOR mutations occurred in 3.8% of unselected CN-AML patients and represented a substantial fraction (17.1%) of CN-AML patients showing the same genotype as the AML index patient subjected to whole-exome sequencing. BCOR somatic mutations were: (1) disruptive events similar to the germline BCOR mutations causing the oculo-facio-cardio-dental genetic syndrome; (2) associated with decreased BCOR mRNA levels, absence of full-length BCOR, and absent or low expression of a truncated BCOR protein; (3) virtually mutually exclusive with NPM1 mutations; and (4) frequently associated with DNMT3A mutations, suggesting cooperativity among these genetic alterations. Finally, BCOR mutations tended to be associated with an inferior outcome in a cohort of 422 CN-AML patients (25.6% vs 56.7% overall survival at 2 years; P = .032). Our results for the first time implicate BCOR in CN-AML pathogenesis.

Thrombohaemorrhagic complications in 101 cases of myeloproliferative disorders: Relationship to platelet number and function

A series of 101 consecutive patients with chronic myeloproliferative disorders including polycythaemia vera, chronic myelogenous leukaemia, idiopathic myelofibrosis and essential thrombocythaemia have been studied. The aim was to establish the incidence of thrombotic and haemorrhagic complications and the possible role played by platelet number and function. The total incidence of haemostatic complications was 21% and the platelet functional tests investigated (platelet aggregation, generation of malondialdehyde, endogenous serotonin, beta-thromboglobulin and platelet coagulant activity) were of little help for predicting these clinical complications.

Autoimmunity and b-cell dysfunction in chronic proliferative disorders of large granular lymphocytes/natural killer cells

Clinical and laboratory findings of B‐cell immune dysfunction were evaluated in ten patients with a large granular lymphocyte/natural killer cell proliferative disease (LGL/NK‐PD). Increased immunoglobulin synthesis with autoantibody formation was documented: polyclonal hypergammaglobulinaemia (six patients), neutrophil autoantibody (one patient), antinuclear antibody (one patient), and rheumatoid factor (five patients). In addition, serum beta2‐microglobulin level was raised in seven patients, a benign monoclonal gammopathy was detected in one, and concurrent B‐type hairy cell leukemia in another. Most patients experienced the complications of hemocytopenia, polyarthritis or rheumatoid arthritis, and immediate allergic reactions to drugs or environmental substances, rather than from symptoms of progressive LGL/NK‐PD. A review of the literature confirms that an increased immunoglobulin production is common in LGL/NK‐PD, and that patients are likely to develop multiple autoantibodies. The incapacity of proliferating, abnormal LGL/NK cells to suppress B‐cell activation and immunoglobulin synthesis, documented by several in vitro studies, offers a pathogenetic explanation for these phenomena. This study shows that an anomalous B‐cell function contributes greatly to the morbidity of disease in LGL/NK‐PD, and points out the utility of investigating the LGL/NK cell system in patients with autoimmune pathologic characteristics of unclear origin.

Granulocyte colony-stimulating factor following peripheral-blood progenitor-cell transplant in non-Hodgkin's lymphoma.

PURPOSE To compare the hematologic recovery after high-dose chemotherapy and circulating peripheral-blood progenitor-cell (PBPC) transplant between patients who received recombinant human granulocyte colony-stimulating factor (G-CSF) (treated group) and those who did not (control group). PATIENTS AND METHODS From December 1992 through June 1994, two sequential and consecutive cohorts of 20 patients each with histologically proven non-Hodgkins lymphoma (NHL) received high-dose chemotherapy (carmustine [BCNU], cytarabine [Ara-C], etoposide and melphalan [BEAM]) followed by PBPC transplant. The first 20 patients were treated with G-CSF (5 micrograms/kg/d) after PBPC administration. Since the time of platelet and leukocyte recovery in this group was short (< 15 days), with a narrow standard deviation from the mean value, the last 20 patients were not given G-CSF. Hematologic recovery, number of febrile days, rate of documented infections, number of hospital days, duration of gastrointestinal complications, platelet and RBC transfusions, and antibiotic requirements were compared in the two groups. RESULTS The two groups of patients were comparable according to disease status, histology, stage, bulky disease bone marrow involvement, elevated lactate dehydrogenase (LDH) level, and median number of infused CD34+ cells and colony-forming units granulocyte-macrophage (CFU-GM). The median time to reach 0.5 x 10(9)/L and 1.0 x 10(9)/L neutrophils was 2 days shorter in G-CSF group, but this difference was not statistically significant. The median times to reach 20 x 10(9)/L and 50 x 10(9)/L platelets were, respectively, 10 and 14 days in the G-CSF group and 11 and 16 days in the control group, but again this was not statistically significant. Moreover, when considering clinically relevant end points including the number of documented infections and antibiotic requirements, platelet transfusions, gastrointestinal toxicity, and days of hospitalization, no differences were demonstrated between the two groups. CONCLUSIONS Provided an optimal dose of circulating progenitors is infused, NHL patients transplanted with PBPC do not benefit by the administration of hematopoietic growth factors.

Dasatinib and low-intensity chemotherapy in elderly patients with Philadelphia chromosome-positive ALL

Prognosis of Philadelphia-positive (Ph(+)) acute lymphoblastic leukemia (ALL) in the elderly has improved during the imatinib era. We investigated dasatinib, another potent tyrosine kinase inhibitor, in combination with low-intensity chemotherapy. Patients older than age 55 years were included in the European Working Group on Adult ALL (EWALL) study number 01 for Ph(+) ALL (EWALL-PH-01 international study) and were treated with dasatinib 140 mg/day (100 mg/day over 70 years) with intrathecal chemotherapy, vincristine, and dexamethasone during induction. Patients in complete remission continued consolidation with dasatinib, sequentially with cytarabine, asparaginase, and methotrexate for 6 months. Maintenance therapy was dasatinib and vincristine/dexamethasone reinductions for 18 months followed by dasatinib until relapse or death. Seventy-one patients with a median age of 69 years were enrolled; 77% had a high comorbidity score. Complete remission rate was 96% and 65% of patients achieved a 3-log reduction in BCR-ABL1 transcript levels during consolidation. Only 7 patients underwent allogeneic hematopoietic stem cell transplantation. At 5 years, overall survival was 36% and up to 45% taking into account deaths unrelated to disease or treatment as competitors. Thirty-six patients relapsed, 24 were tested for mutation by Sanger sequencing, and 75% were T315I-positive. BCR-ABL1(T315I) was tested by allele-specific oligonucleotide reverse transcription-quantitative polymerase chain reaction in 43 patients and detection was associated with short-term relapses. Ten patients (23%) were positive before any therapy and 8 relapsed, all with this mutation. In conclusion, dasatinib combined with low-intensity chemotherapy was well-tolerated and gave long-term survival in 36% of elderly patients with Ph(+) ALL. Monitoring of BCR-ABL1(T315I) from diagnosis identified patients with at high risk of early relapse and may help to personalize therapy.

Liposomal cytarabine is effective and tolerable in the treatment of central nervous system relapse of acute lymphoblastic leukemia and very aggressive lymphoma

Background Treatment of central nervous system relapse in adult acute lymphoblastic leukemia is a challenge and outcome is poor. Liposomal cytarabine has a prolonged half-life and, given intrathecally, has produced high response rates in patients with central nervous system relapse of non-Hodgkins lymphoma. The aim of this study was to evaluate the efficacy and tolerability of liposomal cytarabine in central nervous system relapse of acute lymphoblastic leukemia or Burkitts lymphoma/leukemia. Design and Methods Liposomal cytarabine (50 mg) was given intrathecally together with systemic or intrathecal dexamethasone once every 2 weeks in a phase II European trial. The primary end-point, cytological response in the cerebrospinal fluid after one or two cycles, was evaluated at the time of next treatment. Results Nineteen heavily pretreated patients (median age, 53 years; range 24–76 years) were evaluable: 14 with acute lymphoblastic leukemia and 5 with Burkitt’s lymphoma/leukemia). Complete cytological remission as best response after two cycles of liposomal cytarabine was confirmed in 74% of the patients: 86% of those with acute lymphoblastic leukemia and 40% of those with Burkitt’s lymphoma/leukemia). Nine of the 14 patients who achieved complete remission relapsed after a median of 7 months. The median overall survival was 11 months. Adverse events were observed in 89% of the patients (57% of cycles). Grade III–IV events with potential correlation to liposomal cytarabine occurred in 32% of the patients. The most frequent adverse event was headache. One patient developed severe neurological complications with loss of vision and a conus syndrome. Conclusions Overall, liposomal cytarabine showed excellent antileukemic activity. Toxicity was acceptable but appeared to increase with the number of cycles. Future evaluation in prophylaxis is of interest

Age-Adapted Moderate-Dose Induction and Flexible Outpatient Postremission Therapy for Elderly Patients with Acute Lymphoblastic Leukemia

We report the results of a recent trial in elderly acute lymphoblastic leukemia (ALL) patients (> or = 60 years). Initial chemotherapy consisted of one 14-day course with single-dose idarubicin plus vincristine-prednisone-L-asparaginase. Idarubicin was preferred to other anthracyclines because of its shorter time to response. Sequential outpatient postremission therapy included single-dose idarubicin plus vincristine-cyclophosphamide-L-asparaginase pulses, cranial irradiation with intrathecal methotrexate-cytarabine, flexible weekly vincristine-cyclophosphamide alternating with cytarabine-teniposide, and two-year standard maintenance with mercaptopurine-methotrexate. Granulocyte colony-stimulating factor (G-CSF) was added to induction and early consolidation courses. Twenty-two patients mainly with high-risk features entered the study: median age was 64 years (60-73), 40% of cases were CD10- B-lineage and T-lineage ALL, 38% of CD10+ B-lineage ALL carried a BCR-ABL rearrangement, while 23% coexpressed myeloid antigen, 86% had L2 morphology, 50% had a blast count greater than 10 x 10(9)/1, 54% had hepato-splenomegaly and lymphadenopathy. The complete remission (CR) rate after induction therapy was 59%. A partial remission was obtained in two cases. There were four early deaths (18%) and three refractory ALL (14%). Median time to response was 21 days. With G-CSF, the median duration of absolute neutropenia was 10.5 days. Flexible postremission therapy was very well tolerated, causing no major toxicity. With a median follow-up of 2.6 years, 3 patients remain alive in first CR (23%), 2 of whom at 21.3 months and 39.6 months, respectively. Median survival of responders was 12 months compared to only 1.2 months for nonresponders (p < 0.001). This moderate-dose idarubicin-containing and G-CSF-supported regimen was associated with a high early remission rate in elderly ALL. Postremission therapy results were modest, though not appreciably different from the general experience in this patient population. Because further escalation of drug intensity appears unjustified, attempts to document and reverse drug resistance patterns and restore a dysregulated apoptosis must be considered.