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Bone marrow transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia.

Philadelphia chromosome (Ph1)-positive acute lymphoblastic leukemia (ALL) has a poor prognosis when treated with conventional chemotherapy. We analyzed the outcome of 67 HLA-identical sibling bone marrow transplants (BMTs) for Ph1-positive ALL reported to the International Bone Marrow Transplant Registry (IBMTR). Twenty-one of 67 (31%) transplant recipients survived in continuous complete remission more than 2 years after transplant. Two-year actuarial probabilities (95% confidence interval) of leukemia-free survival were 38% (23% to 55%) for 33 patients transplanted in first remission, 41% (23% to 61%) for 22 patients transplanted after relapse, and 25% (9% to 53%) for 12 patients failing to achieve remission with conventional chemotherapy. These data indicate that transplants are effective treatment for Ph1-positive ALL.

Adolescent↗

Minor myeloid component in Ph chromosome-positive acute lymphoblastic leukaemia: correlation with cytogenetic pattern and implication for poor response to therapy.

Morphological, immunological and cytogenetic features were studied in 27 adults presenting with Ph chromosome-positive acute lymphoblastic leukaemia (ALL), in correlation with clinical outcome. Twenty patients (group 1) were diagnosed as having typical ALL according to the FAB criteria supported by immunological findings. Less than 1% blast cells with azurophilic granules were detected in all cases. Myeloid cytochemistry, i.e. peroxidase and Sudan black-B stain, was negative in all cases. A minor phenotype deviation consisting of the expression of the CD13 myeloid-associated marker was detected in two patients. In seven patients (group 2) a diagnosis of ALL with a minor myeloid component was made because of the presence of a majority of lymphoid blasts and of 5-15% blast cells with morphological cytochemical and immunological features of the myeloid lineage. Abnormal metaphases were found in 6/20 (30%) patients in group 1, compared with 7/7 (100%) patients in group 2. All patients were treated by antilymphoid regimens; however, complete remission was achieved in 17/20 (85%) patients in group 1 versus 1/7 (14.3%) patients in group 2. Median survival was 16 months, range < 1-120+ in group 1 and 9 months, range < 1-15 in group 2. It is concluded that morphological, immunological and cytogenetic studies allow for the recognition of two cytological subsets of Ph+ ALL. The presence of a minor myeloid component in otherwise typical Ph chromosome-positive ALL may be associated with a distinct cytogenetic pattern and poor responses to antilymphoid therapy.

Adult↗

Immune response to Philadelphia chromosome-positive acute lymphoblastic leukemia induced by expression of CD80, interleukin 2, and granulocyte-macrophage colony-stimulating factor.

We examined the potential of generating an immune response against Philadelphia chromosome-positive acute lymphoblastic leukemia. The immunostimulatory molecules chosen for this study were the cytokines IL-2 and GM-CSF and the costimulatory ligand CD80 (B7.1). We used a murine model based on a BALB/c pre-B cell line, BM185wt, in which leukemia is induced by the p185 BCR-ABL oncogenic product, which reproduces Philadelphia chromosome-positive ALL. BM185wt cells were transduced with retroviral vectors and the transduced clones expressing mIL-2, mGM-CSF, or mCD80 were used for challenge. Expression of the immunomodulators by BM185 cells was correlated with delay in leukemia development in immunocompetent mice, but not in immunodeficient mice, indicating an immune response against the modified leukemia cells. Expression of CD80 caused leukemia rejection in 50% of the cohort, which was associated with the CD4+ and CD8+ T cell-dependent development of anti-leukemia cytotoxic T lymphocytes. Furthermore, mice surviving the BM185/CD80 challenge or preimmunized with irradiated BM185/CD80 cells developed an immune response against subsequent challenge with the parental leukemia. These studies provide evidence that immunotherapeutic approaches can be developed for the treatment of ALL.

Adjuvants, Immunologic↗

A novel variant of the bcr-abl fusion product in Philadelphia chromosome-positive acute lymphoblastic leukemia.

Two patients with Philadelphia chromosome-positive acute lymphoblastic leukemia showed novel variants of the chimeric bcr-abl mRNA. The bcr-abl breakpoint region on cDNA derived from the chimeric mRNA was amplified using the polymerase chain reaction (PCR). Sequence analysis of the breakpoint-containing fragment showed that in both patients exon a2 of the abl gene was deleted, giving rise to an in-frame joining at the mRNA level of 5' bcr sequences to the abl exon a3. These findings were confirmed by Southern blot analysis and cloning of chromosomal DNA. Protein studies showed a bcr-abl protein with heightened tyrosine kinase activity in blast cells of both patients: one of the P190 type, the other of the P210 type. The significance of these findings and the role of this new type of translocation in the disregulation of the abl gene are discussed.

Adult↗

Outcome of treatment in children with Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: Children with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL) have a poor prognosis, and there is no consensus on the optimal treatment for this variant of ALL. METHODS: We reviewed the medical records of patients with Ph-positive ALL who were treated with intensive chemotherapy, with or without bone marrow transplantation, by 10 study groups or large single institutions from 1986 to 1996. Data on 326 children and young adults, who ranged in age from 0.4 to 19.9 years (median, 8.1), were analyzed to determine the rate of complete remission and the probability of event-free, disease-free and overall survival according to standard prognostic factors and type of treatment. RESULTS: The 267 patients who achieved a complete remission after induction chemotherapy (82 percent) were stratified into three subgroups according to the age and leukocyte count at the time of diagnosis: those with the best prognosis (a leukocyte count of less than 50,000 per cubic millimeter and an age of less than 10 years; 95 patients); those with an intermediate prognosis (intermediate-risk features; 92 patients); and those with the worst prognosis (a leukocyte count of more than 100,000 per cubic millimeter; 80 patients). The estimates of disease-free survival at five years (+/-SE) were 49+/-5 percent) for patients with the best prognosis), 30+/-5 percent (for those with an intermediate prognosis), and 20+/-5 percent (for those with the worst prognosis) (P<0.001 for the overall comparison). We also found that transplantation of bone marrow from an HLA-matched related donor offered significantly greater benefit than intensive chemotherapy alone in terms of protecting patients from relapse or other adverse events (relative risk, 0.3; 95 percent confidence interval, 0.2 to 0.5; P<0.001). This finding was consistent in all three groups. CONCLUSIONS: Unlike the usual type of all, Ph-positive ALL is associated with a poor prognosis. Nevertheless, in some patients with favorable prognosis features, the disease can be be controlled by intensive chemotherapy. Transplantation of bone marrow from an HLA-matched related donor is superior to other types of transplantation and to intensive chemotherapy alone in prolonging initial complete remissions.

Adolescent↗

Minimal residual disease-based role of imatinib as a first-line interim therapy prior to allogeneic stem cell transplantation in Philadelphia chromosome-positive acute lymphoblastic leukemia.

Fourteen adults with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) were studied to evaluate the role of imatinib prior to allogeneic stem cell transplantation (SCT). Of these, 12 patients were in complete hematologic response (CHR), and 2 were refractory. Imatinib was administered as an interim schedule after each chemotherapy course. After the first imatinib cycle, 11 patients remained in sustained CHR with a decrease in the BCR-ABL/ABL ratios (0.89 logs), and one refractory patient achieved CHR. Meanwhile, 2 patients were resistant to imatinib. Ten patients receiving a second imatinib cycle following consolidation showed sustained CHR, including 2 molecular CR, with a further decrease in the BCR-ABL/ABL ratios (0.19 logs). Twelve patients underwent SCT in a favorable status, and of these, 11 are still alive in a leukemia-free status at 9 to 28+ months after SCT. First-line imatinib interim therapy appears to be a useful strategy to bridge the time to SCT for patients with Ph+ ALL.

Adult↗

Infusion of tumor-contaminated bone marrow for autologous rescue after high-dose therapy leading to long-term remission in a patient with relapsed Philadelphia chromosome-positive acute lymphoblastic leukemia.

We report a female patient with relapsed Philadelphia chromosome-positive acute lymphoblastic leukemia remaining in long-term second remission after high-dose radiochemotherapy followed by autologous stem cell rescue with bone marrow showing evidence of residual disease. The Philadelphia chromosome and a positive signal for the BCR/ABL p185 translocation by the polymerase chain reaction were detected in the harvested marrow. After mafosfamide-purged marrow failed to engraft, her unpurged 'back-up' bone marrow was also infused. Control marrow examinations after recovery were repeatedly positive for the BCR/ABL translocation on PCR analysis turning negative 30 months after high-dose therapy. She remains in unsustained complete clinical remission for 48+ months showing no evidence of leukemia by cytological and cytogenetic analyses.

Adult↗

[Cytogenetic and clinical features of Philadelphia chromosome positive leukemias].

The Philadelphia chromosome defines chronic myeloid leukemia, and is mostly based on a translocation t(9;22) with a typical BCR-ABL rearrangement which also occurs in so called atypical translocations. The transformation of chronic myeloid leukemia is associated with clonal evolution in 80% of cases. The appearance of an isochromosome 17q unequivocally heralds the onset of a myeloid type of blast crisis. Treatment of Ph-positive CML has still to be considered palliative except for allogeneic bone marrow transplantation. The Philadelphia chromosome is also found in about 20% of patients with acute lymphoblastic leukemia and in about 2% of patients with nonlymphoblastic leukemia. It is associated with a poor prognosis. Molecular and cytogenetic findings help differentiating between de novo acute leukemia and blast crisis of chronic myeloid leukemia.

Blast Crisis↗

Approval summary: imatinib mesylate capsules for treatment of adult patients with newly diagnosed philadelphia chromosome-positive chronic myelogenous leukemia in chronic phase.

PURPOSE: The purpose is to describe the Food and Drug Administration (FDA) review and approval of imatinib (Gleevec; Novartis Pharmaceuticals, East Hanover, NJ) for treatment of adult patients with newly diagnosed Philadelphia chromosome-positive chronic myelogenous leukemia (CML) in chronic phase. EXPERIMENTAL DESIGN: The FDA reviewed data in electronic format from a randomized controlled clinical trial of 1106 adult patients with newly diagnosed Philadelphia chromosome-positive CML in chronic phase, comparing imatinib with the combination of IFN-alpha and cytarabine. RESULTS: Imatinib showed clinically and statistically significantly better results for time-to-progression to accelerated phase or blast crisis, progression-free survival, complete hematological response rate, and cytogenetic response rate. With a median follow-up of 14 months, a maximum follow-up of 19.5 months, and an expected median survival of 5-6 years on the IFN-alpha/cytarabine control arm, few of the expected progressions to accelerated or blast phase or deaths have occurred. Imatinib was also better tolerated. Edema, nausea, rigors, neutropenia, and headache were more frequent in women. Only 57% of the IFN-alpha target dose was administered, and only 68% of patients received any cytarabine. However, this does not appear to adequately explain the superiority of imatinib observed in this trial. Results of a population pharmacokinetic study in a subgroup of 371 patients and a separate rifampin-imatinib drug-drug interaction study in healthy volunteers are presented. CONCLUSIONS: On December 20, 2002, imatinib was granted accelerated approval under subpart H, rather than regular approval. Follow-up is short compared with the natural history of chronic phase CML or more mature results with established therapies such as IFN-alpha or transplantation. If imatinib should stop working after 1.5-2 years, the results could be importantly different from the present analysis. As a Phase IV postmarketing commitment, the applicant has agreed to provide follow-up reports on this imatinib study annually for the next 6 years.

Adult↗

Dicentric (19;21)(p13;p13), a novel chromosomal abnormality occurring in a case of Philadelphia chromosome-positive acute lymphoblastic leukemia.

We report on a patient with Philadelphia chromosome-positive acute lymphoblastic leukemia, who acquired a novel chromosomal abnormality, a dic(19;21)(p13;p13), during relapse of the disease. The cytogenetic result was confirmed by fluorescence in situ hybridization using alpha-satellite and library probes specific for chromosomes 19 and 21, respectively, as well as a chromosome 19q13.1-specific DNA probe. In our case, the dic(19;21) represents a secondary genetic change and was associated with disease progression and poor prognosis.

Adult↗

A foreign beta-globin gene in transgenic mice: integration at abnormal chromosomal positions and expression in inappropriate tissues.

We have investigated the chromosomal location, inheritance, and expression of a cloned rabbit beta-globin gene introduced into the mouse germ line by microinjection into mouse eggs. Experiments utilizing in situ hybridization to metaphase chromosomes show that the gene has integrated into one or two different chromosomal loci in each of five mouse lines analyzed. Each locus contains between three and forty copies of the foreign DNA sequence arranged in a tandem array, and the sequences at each locus are stably inherited as a single Mendelian marker. Neither globin mRNA nor polypeptides encoded by the rabbit beta-globin gene are detected in erythroid cells in the seven transgenic lines examined, indicating that the expression of the foreign gene is not correctly regulated. However, in two of the mouse lines, rabbit beta-globin transcripts are found at a low level in specific, although inappropriate, tissues: skeletal muscle in one line and testis in another line. These unusual patterns of beta-globin gene transcription are heritable traits in the two mouse lines and may result from the beta-globin gene's integration at abnormal chromosomal positions.

Animals↗

Ph-Chromosome-positive chronic myeloid leukemia with associated bone marrow mastocytosis.

The concurrent development of chronic myeloid (CML) or myelomonocytic (CMML) leukemia in patients with systemic mastocytosis (SM) is a well recognized phenomenon. Although the leukemia often resembles CML in morphological and in clinical terms, a Ph-Chromosome-positive variant has not been reported in SM so far. We here describe a 43-year-old female patient with typical Ph-Chromosome-positive CML in whom a co-existing bone marrow mastocytosis, a special subvariant of SM, was diagnosed. RT-PCR analysis revealed the typical p210 kDa form of BCR/ABL in leukemic cells. The diagnosis SM was based on the typical focal aggregates of spindle-shaped mast cells (MC) in the bone marrow, expression of CD25 in MC, and the c-kit mutation D816V, which was detectable in microdissected bone marrow MC, but not in microdissected leukemic cells, suggesting the presence of two different (sub)clones of neoplastic cells. Therapy with the BCR/ABL-targeting drug Imatinib (STI571) resulted in complete cytogenetic remission of CML. Together, our case provides further evidence for the biologic diversity of leukemias that may occur in patients with SM. The exact knowledge of the pathology and target-profile of the associated leukemias in SM have important therapeutic implications.

Adult↗

Development and progression of a Philadelphia-chromosome-negative acute myelocytic leukemia clone in a patient with Philadelphia-chromosome-positive chronic myelocytic leukemia.

We report a patient with typical Philadelphia-chromosome-positive chronic myelocytic leukemia who developed Philadelphia-chromosome-negative acute myelocytic leukemia following autologous stem cell transplantation. The implications of this observation for disease monitoring and treatment are discussed.

Antineoplastic Agents↗

Allogeneic bone marrow transplantation for Philadelphia chromosome-positive chronic myelogenous leukemia in childhood.

Allogeneic bone marrow transplantation (BMT) offers the only potential for long-term control of chronic myelogenous leukemia. From November 1992 to August 1994, we prospectively studied five pediatric patients with Philadelphia chromosome-positive chronic myelogenous leukemia, a unique finding in Taiwan, who were treated with allogeneic BMT at different stages of the disease. Their ages at diagnosis ranged from 2 to 10 years. Four donors were HLA-matched siblings and the other was an HLA-matched unrelated donor. All patients received busulfan (4 mg/kg/day for 4 days) followed by cyclophosphamide (60 mg/kg/day for 2 successive days) as the conditioning regimen. Engraftment was documented within 22 days after transplantation in all five patients. Two out of the four patients in the sibling donor group, both of whom had BMT in the first chronic phase, achieved event-free survival after follow-up for 41 months and 17 months. The other two patients, who had BMT in the second lymphoblastic crisis and the second chronic phase, died within 6 months after transplantation due to lymphoid blastic crisis and complication of cytomegaloviral pneumonitis, respectively. The patient who received marrow from the unrelated donor underwent BMT in the accelerated phase and died within 6 months after transplantation due to myeloid blastic crisis. In conclusion, allogeneic BMT performed in the first chronic phase of childhood Philadelphia chromosome-positive chronic myelogenous leukemia seems to have better results than BMT after the first chronic phase.

Bone Marrow Transplantation↗

A novel Philadelphia chromosome-positive cell line with multipotential properties.

A novel Philadelphia chromosome-positive cell line was established from the peripheral blood of a patient with chronic myelogenous leukemia in megakaryoblastic crisis. This cell line, designated TN922 showed the positive phenotypes for myeloid, monocyte-macrophage, erythroid and megakaryocytic markers. The stimulation with phorbol 12-myristate 13-acetate (PMA) increased the expression of megakaryocytic markers including the platelet peroxidase activity, dimethylsulfoxide or transforming growth factor-beta promoted up-regulation of the erythroid markers. Stimulation with PMA, tumor necrosis factor-alpha or interleukin-6 also brought about the expression of monocytoid markers. These findings indicated that TN922 cell line has the property of acting as multipotential progenitor cells. TN922 cells showed gradual growth in the absence of growth factors but the addition of granulocyte/macrophage colony-stimulating factor (GM-CSF) promoted cell growth. The message of GM-CSF was detected in TN922 cells and the neutralizing antibody against GM-CSF receptor alpha-subunit suppressed cell growth. These results indicated that TN922 cell line proliferates in an autocrine secretion of GM-CSF.

Aged↗

Philadelphia chromosome positive essential thrombocythemia evolving into lymphoid blast crisis.

The Philadelphia chromosome with the classic translocation t(9;22) was detected in all metaphases of a patient with essential thrombocythemia who presented without hematologic signs of chronic myeloid leukemia (CML). After 12 months of treatment with hydroxyurea followed by 6 months of busulfan, the disease transformed into lymphoid blast crisis with the immunophenotype of pre-pre-B cells frequently seen in lymphoid blast crisis of CML. This progression was not associated with karyotypic evolution because lymphoblasts contained only the Philadelphia chromosome. Further clinical course in this patient confirmed the development of a Philadelphia chromosome positive stem cell with predominantly megakaryocytic committment through partially megakaryocytic/lymphoid differentiation to purely lymphoid committment, a previously unreported transformation.

Adult↗