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Acute myeloid leukemia (AML) with deranged core-binding factor beta (CBFβ) is usually associated with a favorable prognosis with 50-70% of patients cured using contemporary treatments. We analyzed the prognostic significance of clinical features on 58 patients with CBFβ-AML aged ≤60 years. Increasing age was the only predictor for survival (P <0.001), with an optimal cut-point at 43 years. White blood cells (WBCs) at diagnosis emerged as an independent risk factor for relapse incidence (P = 0.017), with 1.1% increase of hazard for each 1.0 × 10(9) /L WBC increment. KIT mutations lacked prognostic value for survival and showed only a trend for relapse incidence (P = 0.069)., (Copyright © 2013 Wiley Periodicals, Inc.)

Alemtuzumab serum levels and clinical response after subcutaneous administration (10 mg 3 times/week for six weeks) have been explored in 29 chronic lymphocytic leukemia patients receiving the monoclonal antibody as consolidation. Serum concentrations after each administration gradually increased during the first week and more markedly during weeks 2 and 3, approaching the steady-state at week 6. Absorption continued slowly through the tissues for about 2-3 weeks after the last administration, starting to decrease thereafter. Difference between Responders and Non-responders was statistically significant: maximal concentration (Cmax) was 1.69 μg/mL vs. 0.44 μg/mL; concentration before subcutaneous administration (Cpre-dose) on day 15 was 0.7 vs. 0.21 μg/mL, area under curve (AUC0-12h) was 11.09 vs. 2.26 μgxh/mL for Responders and Non-responders, respectively. Higher systemic exposure to alemtuzumab correlated with a better clinical response and minimal residual disease. Results suggest that an adjusted schedule according to serum level could improve clinical outcome of patients receiving subcutaneous alemtuzumab.

Background: Imatinib slows development of chronic myeloid leukemia (CML). However, available information on morbidity and mortality is largely based on sponsored trials, whereas independent long-term field studies are lacking., Patients and Methods: Consecutive CML patients who started imatinib treatment before 2005 and who were in complete cytogenetic remission (CCyR) after 2 years (± 3 months) were eligible for enrollment in the independent multicenter Imatinib Long-Term (Side) Effects (ILTE) study. Incidence of the first serious and nonserious adverse events and loss of CCyR were estimated according to the Kaplan-Meier method and compared with the standard log-rank test. Attainment of negative Philadelphia chromosome hematopoiesis was assessed with cytogenetics and quantitative polymerase chain reaction. Cumulative incidence of death related or unrelated to CML progression was estimated, accounting for competing risks, according to the Kalbleisch-Prentice method. Standardized incidence ratios were calculated based on population rates specific for sex and age classes. Confidence intervals were calculated by the exact method based on the χ(2) distribution. All statistical tests were two-sided., Results: A total of 832 patients who were treated for a median of 5.8 years were enrolled. There were 139 recorded serious adverse events, of which 19.4% were imatinib-related. A total of 830 nonserious adverse events were observed in 53% of patients; 560 (68%) were imatinib-related. The most frequent were muscle cramps, asthenia, edema, skin fragility, diarrhea, tendon, or ligament lesions. Nineteen patients (2.3%) discontinued imatinib because of drug-related toxic effects. Forty-five patients lost CCyR, at a rate of 1.4 per 100 person-years. Durable (>1 year) negative Philadelphia chromosome hematopoiesis was attained by 179 patients. Twenty deaths were observed, with a 4.8% mortality incidence rate (standardized incidence ratio = 0.7; 95% confidence interval = 0.40 to 1.10, P = .08), with only six (30%) associated with CML progression., Conclusions: In this study, CML-related deaths were uncommon in CML patients who were in CCyR 2 years after starting imatinib, and survival was not statistically significantly different from that of the general population.

Bendamustine is an old bifunctional alkylating agent that also has potential antimetabolite properties, and only partial cross-resistance with other alkylators. Although it was synthesized in 1963 only few validated study results exist from this early period. More recently, its peculiar mechanism of action has reawakened interest in this drug that has been extensively studied in indolent non-Hodgkin lymphoma (NHL) and in chronic lymphocytic leukemia (CLL). Experience has also been reported in high-grade NHL and Hodgkin disease. Based on its unique structure, various strategies can be used for mechanism-based combination chemotherapeutic regimens with bendamustine. Moreover, data indicates that bendamustine when combined with rituximab is a valid therapeutic choice for patients with CLL or low-grade NHL demonstrating refractoriness to standard chemotherapy regimens. Furthermore, its documented favorable toxicity profile makes it a particularly useful treatment option for elderly patients.

Purpose: Treatment with alemtuzumab has resulted in negative responses for minimal residual disease (MRD) in patients with chronic lymphocytic leukemia (CLL). In a prior analysis we demonstrated that it is possible to achieved MRD negativity, as assessed by polyclonality of immunoglobulin heavy chain after consolidation with alemtuzumab. This phase II study evaluated 34 patients with CLL who received alemtuzumab consolidation in an effort to improve the quality of their response to fludarabine-based induction. Subsequent peripheral blood stem-cell (PBSC) collection and transplantation, tolerability, and pharmacokinetics also were assessed., Patients and Methods: Thirty-four patients younger than 65 years who had a clinical response to fludarabine-based induction therapy received alemtuzumab 10 mg subcutaneously three times per week for 6 weeks. PBSCs were collected after mobilization with cytarabine and granulocyte colony-stimulating factor. Blood samples for pharmacokinetics study were taken between days 1 and 31., Results: The complete response rate improved from 35% after fludarabine induction to 79.4% after alemtuzumab consolidation, including 19 patients (56%) who achieved MRD negativity. The most common adverse events were injection-site reactions and fever. Cytomegalovirus reactivation occurred in 18 patients, all of whom were successfully treated with oral ganciclovir. PBSC collection was successful in 24 (92%) of 26 patients, and 18 patients underwent autologous PBSC transplantation. Alemtuzumab plasma concentrations increased gradually during the first 2 weeks and accumulated more rapidly thereafter., Conclusion: Subcutaneously administered alemtuzumab was effective, safe, and well tolerated as consolidation therapy in patients with CLL who responded to fludarabine induction therapy. Subsequent PBSCT was feasible thereafter.

Objective: Alterations in growth factor signaling pathways may be a frequent collaborating event in AML1-ETO-mediated leukemogenesis. Gain-of-function KIT receptor mutations have been reported in adult AML patients, especially those with core binding factor leukemia (CBFL). We have previously reported a new gain-of-function KIT(Asn822Lys) mutation that is constitutively expressed in the Kasumi-1 CBFL cell line, and has recently been described in two childhood AML patients. To explore the molecular basis of the effects of this mutation in the appropriate context of hemopoietic dysregulation, we investigated KIT downstream signaling in the Kasumi-1 cell line by means of STI 571 (Imatinib, Gleevec) pharmacological inhibition., Materials and Methods: We investigated KIT(Asn822Lys) mutant-initiated signaling in Kasumi-1 cell line, and characterized the inhibitory effect of the STI 571 protein tyrosine kinase inhibitor on downstream signaling., Results: The use of STI 571-mediated inhibition impaired the tyrosine phosphorylation of KIT(Asn822Lys) and its association with the p85 subunit of phosphatidylinositol 3'-kinase (p85PI3K). The downstream constitutive phosphorylation of JNK1/2 and STAT3 was also significantly inhibited, but STI 571 had no effect on the constitutive activation of Akt, thus suggesting that it is due to other signaling in Kasumi-1 cells. STI 571 inhibited the KIT-mediated proliferation of Kasumi-1 cells in a dose-dependent manner., Conclusions: These findings show the role of PI3K in KIT(Asn822Lys)-mediated constitutive activation through the Akt-independent downstream signaling pathway of JNK, and also demonstrate the mutant's susceptibility to STI 571, which may therefore have therapeutic potential in CBFL patients with susceptible KIT mutations.

Aim of this study is to investigate the capability of Imatinib to induce an anti-leukemic effect in Core Binding Factor (CBF)-leukemia patients presenting either with extracellular juxtamembrane or kinase KIT mutations. On the basis of a screening analysis for KIT mutations, two patients with a kinase mutation and one with extracellular juxtamembrane mutation, in first or subsequent leukemic relapse, received 400mg Imatinib twice daily for 30 days. After Imatinib discontinuation, bone marrow cells were re-tested to assess the KIT mutational status and the chromosomal set. In our experience, none of the treated patients had a response by standard criteria; in particular, we did not observe any activity against acute myeloid leukemia (AML) associated with KIT kinase mutations. However, in the patient with extracellular juxtamembrane mutation, Imatinib seems to have some clinical beneficial effect and, most important, is able to abrogate the leukemic subclone carrying the mutation. Whether Imatinib, in combination with other agents, may play a role in the treatment of AML with more sensitive extracellular juxtamembrane KIT mutation remains to be determined.

Blast crisis is the most advanced stage of chronic myelogenous leukemia (CML) and is highly refractory to therapy. CML is caused by expression of the chimeric BCR-ABL tyrosine kinase oncogene, the product of the t(9;22) Philadelphia translocation. Imatinib (Glivec, formerly STI571) is a rationally developed, orally administered inhibitor of the Bcr-Abl tyrosine kinase. A total of 260 patients with CML were enrolled in a phase II trial, of whom 229 had a confirmed diagnosis of CML in blast crisis. Patients were treated with imatinib in daily oral doses of 400 mg or 600 mg. Imatinib induced hematologic responses in 52% of patients and sustained hematologic responses lasting at least 4 weeks in 31% of patients, including complete hematologic responses in 8%. For patients with a sustained response, the estimated median response duration was 10 months. Imatinib induced major cytogenetic responses in 16% of patients, with 7% of the responses being complete. Median survival time was 6.9 months. Nonhematologic adverse reactions were frequent but generally mild or moderate. Episodes of severe cytopenia were also frequent and were attributable to the underlying condition and treatment with imatinib. Drug-related adverse events led to discontinuation of therapy in 5% of patients, most often because of cytopenia, skin disorders, or gastrointestinal reactions. These results demonstrate that imatinib has substantial activity and a favorable safety profile when used as a single agent in patients with CML in blast crisis. Additional clinical studies are warranted to explore the efficacy and feasibility of imatinib used in combination with other antileukemic drugs.

Background: Chronic myelogenous leukemia (CML) is caused by the BCR-ABL tyrosine kinase, the product of the Philadelphia chromosome. Imatinib mesylate, formerly STI571, is a selective inhibitor of this kinase., Methods: A total of 532 patients with late--chronic-phase CML in whom previous therapy with interferon alfa had failed were treated with 400 mg of oral imatinib daily. Patients were evaluated for cytogenetic and hematologic responses. Time to progression, survival, and toxic effects were also evaluated., Results: Imatinib induced major cytogenetic responses in 60 percent of the 454 patients with confirmed chronic-phase CML and complete hematologic responses in 95 percent. After a median follow-up of 18 months, CML had not progressed to the accelerated or blast phases in an estimated 89 percent of patients, and 95 percent of the patients were alive. Grade 3 or 4 nonhematologic toxic effects were infrequent, and hematologic toxic effects were manageable. Only 2 percent of patients discontinued treatment because of drug-related adverse events, and no treatment-related deaths occurred., Conclusions: Imatinib induced high rates of cytogenetic and hematologic responses in patients with chronic-phase CML in whom previous interferon therapy had failed.

BACKGROUND: The combination of fludarabine, cyclophosphamide, and rituximab (FCR) has produced promising results in chronic lymphocytic leukemia and other lymphoproliferative disorders. The authors report the final results from a multicenter, prospective study examining FCR in Waldenstrom macroglobulinemia (WM). METHODS: Forty-three patients with symptomatic WM that was untreated or pretreated with 1 line of chemotherapy received rituximab 375 mg/m2 intravenously on day 1 and fludarabine 25 mg/m2 and cyclophosphamide 250 mg/m2 intravenously on days 2 through 4. FCR was repeated every 28 days for up to 6 courses. RESULTS: The overall response rate was 79%, and the major response rate of 74.4%, including 11.6% complete remissions (CRs) and 20.9% very good partial remissions. An amelioration of the quality of responses was observed during follow-up, leading to 18.6% of CRs. No differences in terms of responses were observed among previously treated or untreated patients. Among the clinical and laboratory features that were considered, only the β2-microglobulin level had a significant impact in terms of achieving a major response. The major toxicity reported was grade 3/4 neutropenia, which occurred in 45% of courses and was the main reason for treatment discontinuation. After the end of treatment, 19 patients (44%) had long-lasting episodes of neutropenia. Three patients developed myelodysplastic syndrome during follow-up. CONCLUSIONS: The FCR regimen was capable of neutralizing adverse prognostic factors and proved to be active in patients with WM, leading to rapid disease control and good-quality responses. Because myelosuppression was the main concern, further studies are warranted to optimize dosages and treatment duration. Cancer 2011;. © 2011 American Cancer Society. [ABSTRACT FROM AUTHOR]

The aim of this phase II trial was to investigate the efficacy of bortezomib plus dexamethasone (Vel-Dex) as induction therapy in patients with multiple myeloma (MM) and to define the role of intensification before transplantation. Fifty-seven patients were treated with four courses of Vel-Dex, two cycles of dexamethasone, cyclophosphamide, etoposide and cisplatin (DCEP), and a single autologous transplant. Fourteen patients (25%) went off-study: seven after Vel-Dex, seven after DCEP. All patients yielded high numbers of stem cells (median CD34+ cells 7.5 × 106/kg); 54 of the 57 patients (94%) collected ≥4 × 106/kg CD34+ cells, 60% with a single leukapheresis. The overall response rate (ORR) after Vel-Dex was 86% (70% had a very good partial response [VGPR] or better) regardless of cytogenetic abnormalities and International Staging System stage (ISS). The response at the end of the two DCEP cycles remained unchanged in 35 patients (70%), worsened in 15 (20%), and improved in 5 (10%). Because of the consistent drop-out, the ORR in intention-to-treat analysis decreased significantly from 86% after Vel-Dex to 76% after DCEP, and 73% after transplantation. However, when considering the subset of 43 patients who completed the program, the ORR was 96% (complete response 39%, VGPR 41%, partial response 16%). In conclusion, Vel-Dex produces high response rates, improves stem cell collection, and overcomes the need for intensification before autologous transplantation. [ABSTRACT FROM AUTHOR]