Myeloid neoplasms after breast cancer: "therapy-related" not an independent poor prognostic factor.

Two hundred and thirty-five consecutive patients presenting to a single center with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) after breast cancer treatment were compared with matched patients with de novo AML or MDS. There was no significant difference in median overall survival (OS) times between patients with therapy-related AML and those with de novo AML (8.7 months vs.10.2 months; p = 0.17). Patients with therapy-related MDS had slightly lower median baseline platelet counts and a higher frequency of poor cytogenetics than those with de novo MDS, but the two groups had similar OS times (13.6 months vs. 18.9 months; p = 0.06). Multivariate analysis revealed that cytogenetic risk, baseline white blood cell count, age and performance status were predictive for OS time in AML and that cytogenetic risk and performance status were predictive for OS time in MDS. Having therapy-related disease is not an independent risk factor in patients with myeloid neoplasms and with a history of breast cancer. Clinical trials should be designed to serve both populations.

The Addition of All-Trans Retinoic Acid to Chemotherapy May Not Improve the Outcome of Patient with NPM1 Mutated Acute Myeloid Leukemia.

BACKGROUND: Previous studies have suggested that NPM1 mutations may be a marker for response to all-trans retinoic acid (ATRA) given as an adjunct to intensive chemotherapy in older patients with acute myeloid leukemia (AML). PATIENTS AND METHODS: We examined the impact of the addition of ATRA among patients with diploid cytogenetics treated on a randomized phase II study of fludarabine + cytarabine + idarubicine ± G-CSF ± ATRA with available data on their NPM1 mutation status. Between September 1995 and November 1997, 215 patients were enrolled in the study. Among them, 70 patients had diploid cytogenetic and are the subjects of this analysis. RESULTS: The median age of the 70 patients was 66 years (range 23-87). Twenty (29%) of patients had NPM1 mutations. Among them 7 (35%) did and 13 (65%) did not receive ATRA in combination with chemotherapy. Complete remission (CR) was achieved in 71% of patients treated with ATRA as compared to 69% without ATRA (P = 0.62). With median follow-up of 12.5 years, the overall survival (OS), event-free survival (EFS), and relapse-free survival (RFS) were similar among patients who received ATRA compared to no ATRA regardless of NPM1 mutation status. CONCLUSION: The addition of ATRA to intensive chemotherapy did not affect the overall outcome of patients with AML regardless of NPM1 mutation status.

Tet2 loss leads to increased hematopoietic stem cell self-renewal and myeloid transformation.

Somatic loss-of-function mutations in the ten-eleven translocation 2 (TET2) gene occur in a significant proportion of patients with myeloid malignancies. Although there are extensive genetic data implicating TET2 mutations in myeloid transformation, the consequences of Tet2 loss in hematopoietic development have not been delineated. We report here an animal model of conditional Tet2 loss in the hematopoietic compartment that leads to increased stem cell self-renewal in vivo as assessed by competitive transplant assays. Tet2 loss leads to a progressive enlargement of the hematopoietic stem cell compartment and eventual myeloproliferation in vivo, including splenomegaly, monocytosis, and extramedullary hematopoiesis. In addition, Tet2(+/-) mice also displayed increased stem cell self-renewal and extramedullary hematopoiesis, suggesting that Tet2 haploinsufficiency contributes to hematopoietic transformation in vivo.

RAS mutations contribute to evolution of chronic myelomonocytic leukemia to the proliferative variant.

PURPOSE: The biological and clinical heterogeneity of chronic myelomonocytic leukemia features renders its classification difficult. Moreover, because of the limited knowledge of the mechanisms involved in malignant evolution, chronic myelomonocytic leukemia remains a diagnostic and therapeutic challenge and a poor prognosis disease. We aimed to verify the biological and clinical significance of the discrimination, based on the leukocyte count, between myelodysplastic chronic myelomonocytic leukemia (MD-CMML) and myeloproliferative chronic myelomonocytic leukemia (MP-CMML). EXPERIMENTAL DESIGN: Peripheral blood samples from 22 patients classified as MD-CMML and 18 as MP-CMML were collected at different time points during disease course, and patients' clinical characteristics were examined. RAS mutational screening was done by sequencing and, for each substitution identified, a highly selective allele-specific PCR was set up to screen all specimens. RESULTS: MP-CMML patients showed a significantly poorer survival (P = 0.003) and a higher frequency of RAS mutations (P = 0.033) by sequencing compared with MD-CMML. Overall, five MD-CMML patients progressed to myeloproliferative disease: in two, allele-specific PCR unveiled low levels of the RAS mutations predominating in the myeloproliferative phase at the time of myelodysplastic disease, documenting for the first time the expansion of a RAS mutated clone in concomitance with chronic myelomonocytic leukemia evolution. Moreover, one of the progressed patients harbored the FLT3-ITD and two MP-CMML patients presented with the JAK2 V617F substitution. All these lesions were mutually exclusive. CONCLUSIONS: Our results strongly suggest RAS mutations to function as a secondary event that contributes to development of the chronic myelomonocytic leukemia variant with the poorer prognosis (MP-CMML) and therefore advise their detection to be implemented in chronic myelomonocytic leukemia diagnostics and monitoring.

Outcome of patients with FLT3-mutated acute myeloid leukemia in first relapse.

Mutations of Fms-like tyrosine kinase-3 (FLT3) have been described in about 30% of patients with acute myeloid leukemia (AML) and are associated with a shorter disease-free and overall survival after initial therapy. We sought to examine whether the presence of these mutations in relapsed disease was also associated with a poor response to salvage chemotherapy by comparing the outcome of 34 patients with diploid cytogenetics and mutated FLT3 (internal tandem duplication mutation, ITD) to 69 patients with normal karyotype and wild-type FLT3 (FLT3-WT) in first relapse. On univariate analysis, patients with mutated FLT3 were less likely to achieve a CR to first salvage compared to FLT3-WT patients (24% vs. 41%; P=0.09). Furthermore, survival was longer for the FLT3-WT patients achieving a second CR after salvage compared to FLT3-mutated patients (P=0.017). Overall, patients with mutated FLT3 had a shorter survival from the time of relapse compared to those with FLT3-WT (P<0.001). The adverse prognostic impact of FLT3 mutations appears to persist beyond the initial treatment.

Genetic characterization of TET1, TET2, and TET3 alterations in myeloid malignancies.

Disease alleles that activate signal transduction are common in myeloid malignancies; however, there are additional unidentified mutations that contribute to myeloid transformation. Based on the recent identification of TET2 mutations, we evaluated the mutational status of TET1, TET2, and TET3 in myeloproliferative neoplasms (MPNs), chronic myelomonocytic leukemia (CMML), and acute myeloid leukemia (AML). Sequencing of TET2 in 408 paired tumor/normal samples distinguished between 68 somatic mutations and 6 novel single nucleotide polymorphisms and identified TET2 mutations in MPN (27 of 354, 7.6%), CMML (29 of 69, 42%), AML (11 of 91, 12%), and M7 AML (1 of 28, 3.6%) samples. We did not identify somatic TET1 or TET3 mutations or TET2 promoter hypermethylation in MPNs. TET2 mutations did not cluster in genetically defined MPN, CMML, or AML subsets but were associated with decreased overall survival in AML (P = .029). These data indicate that TET2 mutations are observed in different myeloid malignancies and may be important in AML prognosis.

Inhibition of mitochondrial metabolism by methyl-2-cyano-3,12-dioxooleana-1,9-diene-28-oate induces apoptotic or autophagic cell death in chronic myeloid leukemia cells.

The initial success of the first synthetic bcr-abl kinase inhibitor imatinib has been dampened by the emergence of imatinib-resistant disease in blast crisis chronic myeloid leukemia. Here, we report that the novel triterpenoid methyl-2-cyano-3,12-dioxooleana-1,9-diene-28-oate (CDDO-Me) potently induced cytotoxicity in imatinib-resistant KBM5 cells expressing the T315I mutation of bcr-abl (24-h EC50, 540 nmol/L). In long-term culture, CDDO-Me abrogated the growth of human parental KBM5 and KBM5-STI cells with 96-h IC50 of 205 and 221 nmol/L, respectively. In addition, CDDO-Me rapidly decreased the viability of murine lymphoid Ba/F3 cells expressing wild-type p210 as well as the imatinib-resistant E255K and T315I mutations of bcr-abl. The low-dose effects of CDDO-Me are associated with inhibition of mitochondrial oxygen consumption, whereas the cytotoxic effects appear to be mediated by a rapid and selective depletion of mitochondrial glutathione that accompanies the increased generation of reactive oxygen species and mitochondrial dysfunction. Interestingly, the mitochondriotoxic effects of CDDO-Me are followed by the rapid autophagocytosis of intracellular organelles or the externalization of phosphatidylserine in different cell types. We conclude that alterations in mitochondrial function by CDDO-Me can result in autophagy or apoptosis of chronic myeloid leukemia cells regardless of the mutational status of bcr-abl. CDDO-Me is in clinical trials and shows signs of clinical activity, with minimal side effects and complete lack of cardiotoxicity. Studies in leukemias are in preparation.

Phase I study of alternate-week administration of tipifarnib in patients with myelodysplastic syndrome.

PURPOSE: To determine the safety and describe the antitumor activity of tipifarnib in patients with myelodysplastic syndrome (MDS) using an alternate-week schedule. EXPERIMENTAL DESIGN: Patients with MDS were given tipifarnib, escalating from 100 mg orally twice daily until the maximum tolerated dose for 8 weeks followed by maintenance therapy (same dose/schedule) for patients with stable disease or better. RESULTS: Sixty-three patients were treated. The most common toxicity was myelosuppression (60% of patients). Twenty percent of patients had no side effects. Nonhematologic toxicities included fatigue (20%), skin rash (9%), diarrhea (16%), increase in liver transaminases (14%) and bilirubin (11%), and nausea (11%). Dose-limiting toxicities of ataxia (n = 1), fatigue (n = 1), nausea (n = 1), and neutropenic fever (n = 2) occurred at tipifarnib doses above 1,200 mg/d. Sixteen of 61 (26%) evaluable patients responded (3 complete remissions and 13 hematologic improvements) with major platelet responses being most common (11 of 16 responders). There was no obvious dose-response relationship. Four of the 16 responders (25%; including a complete responder) were treated at the lowest dose level (100 mg twice daily). Only one responder had a Ras mutation. Giving tipifarnib resulted in potent inhibition of farnesyl transferase (usually more than 75%) in peripheral blood mononuclear cells regardless of dose. Partial farnesyl transferase inhibition persisted during the week off. CONCLUSIONS: Alternate-week tipifarnib is active and well tolerated in patients with MDS at doses up to and including 600 mg orally twice daily. The biological activity of tipifarnib is not dependent on dose.

Diagnosis and management of chronic myelomonocytic leukemia.

Chronic myelomonocytic leukemia is a heterogeneous hematologic malignancy classified among the mixed myelodysplastic/myeloproliferative diseases by the World Health Organization because of its myelodysplastic and myeloproliferative characteristics. In the proliferative form, diagnosis should include screening for known molecular abnormalities associated with constitutively active tyrosine kinases, which may be candidates for targeted therapies. Because patient life expectancy is highly variable and there is no consensus on optimal therapy, clinicians are advised to rely on a specific risk-oriented scoring system for clinical decision-making for individual patients. Although supportive care represents the milestone for disease management, novel active agents such as hypomethylating drugs recently have become available, so that the current therapeutic armamentarium now includes different treatment alternatives. Allogeneic stem cell transplantation may represent a curative option in highly selected patients.

FLT3 mutations confer enhanced proliferation and survival properties to multipotent progenitors in a murine model of chronic myelomonocytic leukemia.

Despite their known transforming properties, the effects of leukemogenic FLT3-ITD mutations on hematopoietic stem and multipotent progenitor cells and on hematopoietic differentiation are not well understood. We report a mouse model harboring an ITD in the murine Flt3 locus that develops myeloproliferative disease resembling CMML and further identified FLT3-ITD mutations in a subset of human CMML. These findings correlated with an increase in number, cell cycling, and survival of multipotent stem and progenitor cells in an ITD dose-dependent manner in animals that exhibited alterations within their myeloid progenitor compartments and a block in normal B cell development. This model provides insights into the consequences of constitutive signaling by an oncogenic tyrosine kinase on hematopoietic progenitor quiescence, function, and cell fate.

PEG-IFN-alpha-2b therapy in BCR-ABL-negative myeloproliferative disorders: final result of a phase 2 study.

BACKGROUND: Interferon-alpha (IFN-alpha) has shown significant activity in the treatment of BCR-ABL-negative myeloproliferative disorders (MPDs), particularly essential thrombocythemia (ET) and polycythemia vera (PV). PEG-IFN-alpha-2b is a pegylated IFN-alpha-2b with a significant advantage over nonpegylated form in that it is administered once a week. METHODS: Thirty-eight patients with BCR-ABL-negative MPDs were treated with PEG-IFN-alpha-2b, given subcutaneously weekly, at the starting dose of 3 microg/kg/wk for the first 14 patients and then 2 microg/kg/wk for the next 24 patients, with intent to treat patients as long as they benefited from the therapy. RESULTS: Median age was 54 years. Patient diagnoses were: 13 (34%) ET; 11 (29%) primary myelofibrosis (PMF); 5 (13%) BCR-ABL-negative chronic myeloid leukemia (CML); 4 (10.5%) hypereosinophilic syndrome (HES); 4 (10.5%) PV; and 1 (3%) unclassified myeloproliferative disease (uMPD). Recorded grade 3-4 toxicities were related to fatigue, myelosuppression, and musculoskeletal pain. Ten (26%) patients stopped treatment because of toxicity. Thirteen (34%) patients achieved a complete remission, and 4 (11%) achieved a partial response. Only 1 patient with PMF responded. Median time to response was 5 months. Median duration of response was 20 months. Three patients had a sustained response for >24 months. CONCLUSIONS: PEG-IFN-alpha-2b, with proper dose modifications, is effective in controlling disease in a significant proportion of BCR-ABL-negative MPD patients, particularly ET and PV. However, toxicities encountered with PEG-IFN-alpha-2b therapy are similar to those obtained with conventional IFN-alpha, thus limiting the duration of therapy.

Prognostic factors and risk assessment in chronic myelomonocytic leukemia: validation study of the M.D. Anderson Prognostic Scoring System.

Chronic myelomonocytic leukemia continues to be a poorly understood disease, defined by clinical rather than biological features, with no consensus on optimal therapy. In the past, patients were often assessed for risk using scoring systems developed for other diseases, notably the International Prognostic Scoring System commonly used for myelodysplastic syndrome. The M.D. Anderson Prognostic Scoring System, using hemoglobin, absolute lymphocyte count, peripheral blood immature cells, and bone marrow blasts, was developed specifically for CMML; it was based on retrospective analysis of 213 patients. This report re-examines the validity of this scoring system based on follow-up of the initial cohort and prospectively examines its validity in 250 new patients. Both the original MDAPS system and a modified version derived from data of the initial cohort after extended follow-up (substituting lactate dehydrogenase for bone marrow blasts) effectively stratify both patient cohorts by survival and provide a useful risk assessment tool and additional guidance during treatment decisions.

Prognostic nomogram and index for overall survival in previously untreated patients with chronic lymphocytic leukemia.

The clinical course for patients with chronic lymphocytic leukemia is extremely heterogeneous. The Rai and Binet staging systems have been used to risk-stratify patients; most patients present with early-stage disease. We evaluated a group of previously untreated patients with chronic lymphocytic leukemia (CLL) at initial presentation to University of Texas M. D. Anderson Cancer Center to identify independent characteristics that predict for overall survival. Clinical and routine laboratory characteristics for 1674 previously untreated patients who presented for evaluation of CLL from 1981 to 2004 were included. Univariate and multivariate analyses identified several patient characteristics at presentation that predicted for overall survival in previously untreated patients with CLL. A multivariate Cox proportional hazards model was developed, including the following independent characteristics: age, beta-2 microglobulin, absolute lymphocyte count, sex, Rai stage, and number of involved lymph node groups. Inclusion of patients from a single institution and the proportion of patients younger than 65 years may limit this model. A weighted prognostic model, or nomogram, predictive for overall survival was constructed using these 6 characteristics for 5- and 10-year survival probability and estimated median survival time. This prognostic model may help patients and clinicians in clinical decision making as well as in clinical research and clinical trial design.

Blockade of adaptive defensive changes in cholesterol uptake and synthesis in AML by the addition of pravastatin to idarubicin + high-dose Ara-C: a phase 1 study.

Following exposure to cytotoxic agents, acute myeloid leukemia (AML) blasts elevate cellular cholesterol in a defensive adaptation that increases chemoresistance, but blockade of HMG-CoA reductase with statins restores chemosensitivity in vitro. This phase 1 study evaluated adding pravastatin (PV) (40-1680 mg/day, days 1-8) to idarubicin (Ida) ([12 mg/ (M2 x day), days 4-6]) + high-dose cytarabine (Ara-C; HDAC) [1.5 g/(M2 x day) by CI, days 4-7] in 15 newly diagnosed and 22 salvage patients with unfavorable (n = 26) or intermediate (n = 10) prognosis cytogenetics. Compared with historical experience with Ida-HDAC, the duration of neutropenia and throbmbocytopenia and the toxicity profile were unaffected by the addition of PV. During PV loading (day 0-4) serum triglyceride and total and LDL cholesterol levels decreased in nearly all patients. Pharmacokinetic studies demonstrated higher and more sustained serum PV levels with PV doses above 1280 mg/day. CR/CRp was obtained in 11 of 15 new patients, including 8 of 10 with unfavorable cytogenetics, and 9 of 22 salvage patients. An MTD for PV + Ida-HDAC was not reached. Addition of PV to Ida-HDAC was safe, and the encouraging response rates support conducting further trials evaluating the effect of cholesterol modulation on response in AML.

Mutations and promoter methylation status of NPM1 in myeloproliferative disorders.

We determined mutations and promoter methylation status of NPM1 using pyrosequencing in 199 samples of myeloid neoplasia including myeloproliferative disorders (MPD). The mutations were present in 4% of chronic myelomonocytic leukemia, but not in other MPD or myelodysplastic syndromes. Promoter methylation was rare, and was found in only three samples of MPD.

Arsenic derivatives in hematologic malignancies: a role beyond acute promyelocytic leukemia?

The importance of arsenic trioxide (As2O3) has been underscored over the last decade due to its efficacy against acute promyelocytic leukemia (APL), a disease in which this agent has been associated with complete hematologic and molecular remission rates of 87% and 83%, respectively. The different molecular mechanisms of action of As2O3 suggest its applicability in hematologic malignancies other than APL. However, responses obtained thus far have consisted of improvements in signs and symptoms without the elimination of a given disease. Toxicities derived from As2O3 are significant but manageable and reversible. However, the risk/benefit ratio of As2O3 in hematologic malignancies other than APL is still unclear. The development of new generations of orally bioavailable inorganic, as well as new organic, arsenic compounds with improved toxicity profiles may bolster the therapeutic application of arsenic derivatives in hematologic malignancies such as leukemia, multiple myeloma and myelodysplastic syndromes.

Clinical application and proposal for modification of the International Working Group (IWG) response criteria in myelodysplasia.

The myelodysplastic syndromes (MDSs) are heterogeneous with respect to clinical characteristics, pathologic features, and cytogenetic abnormalities. This heterogeneity is a challenge for evaluating response to treatment. Therapeutic trials in MDS have used various criteria to assess results, making cross-study comparisons problematic. In 2000, an International Working Group (IWG) proposed standardized response criteria for evaluating clinically significant responses in MDS. These criteria included measures of alteration in the natural history of disease, hematologic improvement, cytogenetic response, and improvement in health-related quality of life. The relevance of the response criteria has now been validated prospectively in MDS clinical trials, and they have gained acceptance in research studies and in clinical practice. Because limitations of the IWG criteria have surfaced, based on practical and reported experience, some modifications were warranted. In this report, we present recommendations for revisions of some of the initial criteria.

Pregnancy among patients with chronic myeloid leukemia treated with imatinib.

PURPOSE: Imatinib has potential teratogenicity in animals, but the effect of exposure to imatinib during conception and pregnancy in humans is not known. PATIENTS AND METHODS: The records of all patients with chronic myeloid leukemia (CML) treated with imatinib were reviewed. We report the experience on 19 pregnancies involving 18 patients (10 females and eight males) who conceived while receiving imatinib for the treatment of CML. RESULTS: All female patients discontinued therapy immediately on recognition of pregnancy. Three pregnancies (involving two female patients and one male patient) ended in spontaneous abortion, and one patient had an elective abortion. All other pregnancies were uneventful. Two of the 16 babies had minor abnormalities at or shortly after birth (hypospadias in one baby and rotation of small intestine in one baby) that were surgically repaired. All babies have continued normal growth and development. Among female patients who interrupted therapy, five of nine in complete hematologic remission (CHR) at the time of treatment interruption eventually lost CHR, and six experienced an increase in Philadelphia chromosome-positive metaphases. At a median of 18 months after resuming therapy with imatinib, eight patients had a cytogenetic response (complete in three patients). CONCLUSION: Although there is no evidence that a brief exposure to imatinib during conception and pregnancy adversely affects the developing fetus, most patients lose their response after treatment interruption. Patients receiving imatinib should be advised to practice adequate contraception.

Prognostic significance of monocytosis in patients with myeloproliferative disorders.

Based on clinical and pathological findings, chronic myelomonocytic leukemia (CMML) differs from other myeloproliferative/myelodysplastic disorders by its hallmark, monocytosis. It is unknown whether the presence of monocytosis and the diagnosis of CMML carry a prognostic significance. The present study aimed to determine whether the survival of patients with CMML differs from that of patients with BCR/ABL-negative CML or Ph(1-), BCR/ABL-unknown CML, once other potentially prognostic variables have been accounted for. The records of 485 patients with myeloproliferative/myelodysplastic disorders [CMML, n = 304; BCR/ABL-negative CML, n = 107; Ph(1-), BCR/ABL unknown, n = 74] were analysed. Of the covariates found to be significantly (P < 0.01) associated with survival in univariate and multivariate analyses, the following remained predictive and adversely associated with survival, after accounting for the influence of other covariates: increasing age, white blood cell count, platelets, bone marrow blasts and cellularity, decreasing hemoglobin, abnormal karyotype, and diagnosis of CMML. The diagnosis of CMML is prognostically significant and independently associated with a shorter survival and a higher risk of death than BCR/ABL-negative CML or Ph(1-) BCR/ABL-unknown CML.