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E Montserrat

Publications and source records attributed to E Montserrat.

At least 55 records · Page 3Linked to original sources
PubMed2001

Chronic lymphocytic leukemia: case-based session.

Drs. Hartmut Döhner, Michael J. Keating, Kanti R. Rai and Emili Montserrat form the panel to review chronic lymphocytic leukemia (CLL) while focusing on the clinical features of a particular patient. The pace of progress in CLL has accelerated in the past decade. The pathophysiological nature of this disease, as had been known in the past, was based largely on the intuitive and empiric notions of two leaders in hematology, William Dameshek and David Galton. Now the works of a new generation of leaders are providing us with the scientific explanations of why CLL is a heterogeneous disease, perhaps consisting of at least two separate entities. In one form of CLL, the leukemic lymphocytes have a surface immunoglobulin (Ig) variable region gene that has undergone somatic mutations, with tell-tale markers suggesting that these cells had previously traversed the germinal centers. Such patients have a distinctly superior prognosis than their counterparts whose leukemic lymphocytes IgV genes have no mutations (these are indeed immunologically naive cells), who have a worse prognosis. The introduction of fluorescence in situ hybridization (FISH) technique has provided us with new insights into the diverse chromosomal abnormalities that can occur in CLL, and which have significant impact on the clinical behavior and prognosis of patients with this disease. Major advances in therapeutics of CLL also have occurred during the past decade. Two monoclonal antibodies, Campath-1H (anti-CD52) and rituximab (anti-CD20), and one nucleoside analogue, fludarabine, have emerged as three agents of most promise in the front-line treatment of this disease. Studies currently in progress reflect our attempts to find the most effective manner of combining these agents to improve the overall survival statistics for CLL patients. As in many other hematological malignancies, high dose chemotherapy followed by autologous or HLA-compatible allogeneic stem cells rescue strategies are under study as a salvage treatment for a relatively younger age group of CLL patients with poor prognosis characteristics.

Cytogenetic Analysis↗
PubMed2001

Hypercalcemia as the presenting feature of t-cell lymphoid blast crisis of ph-positive chronic myeloid leukemia.

Hypercalcemia is a rare complication of chronic myeloid leukemia (CML), usually seen in the accelerated or blastic phases of the disease and associated with a poor prognosis. T-cell lymphoid phenotype is also an infrequent finding in the blast crisis (BC) of CML. A CML patient who had hypercalcemia as the presenting feature of a T-cell BC is reported. She was a 78 year-old woman who, at four months of CML diagnosis, developed weakness, bone pain, and mental confusion, with hypercalcemia being subsequently found. Although the peripheral blood and bone marrow were consistent with the chronic phase of CML, mediastinal enlargement, a soft tissue mass adjacent to the iliac bone, and multiple osteolytic lesions were seen. Serum levels of parathyroid hormone (PTH) and PTH-related peptide were normal, whereas the search for a second neoplasm was negative. The hypercalcemia initially responded to conventional treatment, but it reappeared two weeks later. Coincidentally, a high proportion of blast cells of T-cell origin at the cortical thymocyte stage were observed in the patient's peripheral blood and bone marrow, and she died shortly afterwards.

Aged↗
PubMed2001

Microsatellite instability analysis in typical and progressed mantle cell lymphoma and B-cell chronic lymphocytic leukemia.

BACKGROUND AND OBJECTIVES: Microsatellite instability (MSI) is characterized by tumor-associated alterations in the germline size of microsatellite repeats caused by a reduced efficacy of the DNA mismatch repair machinery. The aim of this study was to investigate the presence of MSI in a number of cases of indolent and aggressive mantle cell lymphoma (MCL) and B-cell chronic lymphocytic leukemia (B-CLL) to determine its possible role in the initial development and progression of these disorders. DESIGN AND METHODS: We examined the presence of MSI in 28 B-CLL, 24 typical and 4 transformed B-CLL (Richter's syndrome) and 29 MCL, 19 typical and 10 blastoid variants by using a panel of 10 microsatellite markers and analyzed them using an AbiPrism 310 DNA sequencer. Fisher's exact test was used to compare categorical variables and Mann-Whitney's U-test for continuous variables. RESULTS: MSI alterations were not observed in any case of MCL or Richter's syndrome and in only three (13%) patients with typical B-CLL. Two of these patients also had loss of heterozygosity in one of the 10 sites examined. These patients presented with a more advanced stage, diffuse bone marrow involvement, and poorer performance status than patients without these alterations. INTERPRETATION AND CONCLUSIONS: These findings indicate that MSI is not involved in the pathogenesis or progression of B-CLL and MCL but may appear in a small subset of patients with advanced B-CLL.

Adult↗
PubMed2001

Interferon alpha plus intermittent oral Ara-C ocfosfate (YNK-01) in chronic myeloid leukemia primarily resistant or with minimal cytogenetic response to interferon.

BACKGROUND AND OBJECTIVES: Subcutaneous Ara-C plus interferon (IFN) produces more cytogenetic responses than IFN in chronic myeloid leukemia (CML) but a greater toxicity. The objective of this study was to determine the efficacy and tolerance of IFN plus oral Ara-C ocfosfate (YNK-01) in IFN-resistant CML patients. DESIGN AND METHODS: A phase II pilot study was conducted in 19 CML patients primarily resistant or with minimal cytogenetic response to IFN. Patients were scheduled to receive 6 monthly 14-day cycles of YNK-01 (500 mg/day), with progressive escalation if tolerated, in addition to IFN. Cytogenetic assessment was performed thereafter. RESULTS: Of the first 7 patients, 5 had severe hematologic and 5 moderate gastrointestinal toxicity; IFN was reduced in 6, YNK-01 in 5, and treatment discontinued in 2; hematologic response was achieved in 2 of the 5 evaluable patients. In the following 4 patients the Ara-C was reduced to 300 mg: 2 had severe hematologic and 2 moderate gastrointestinal toxicity; IFN and Ara-C were reduced in 2 patients and treatment discontinued in 2 due to progression or toxicity; the other 2 achieved a minor cytogenetic response, progressing in one to a major response after 6 more cycles. In 8 patients the starting Ara-C dose was 200 mg: 5 had moderate-severe hematologic and 5 mild gastrointestinal toxicity; IFN was reduced in 5, Ara-C in 1, and treatment discontinued in 1; Ara-C was increased in 7 cases; hematologic response was obtained in 4 patients, 2 of whom attained a minor and 1 a major cytogenetic response. INTERPRETATION AND CONCLUSIONS: These results provide background for future studies aimed at ascertaining the role of oral Ara-C combined with IFN or STI571 in newly diagnosed CML.

Adult↗
PubMed2001

Thalidomide in refractory and relapsing multiple myeloma.

Patients with multiple myeloma (MM) refractory to chemotherapy can only benefit from supportive measures and have a very short survival. Thalidomide has recently shown antitumor activity in patients with refractory myeloma. Twenty-three patients (12 men and 11 women; median age, 72 years) with advanced MM were treated with thalidomide. Sixteen patients had refractory disease and seven had untested relapse. The median dose of thalidomide was 400 mg d (range, 200 to 800 mg/d). The drug was generally administered in two divided doses. Five patients required treatment discontinuation because of toxicity. Twelve of 23 patients (52%) responded. Three (13%) achieved a partial response, with greater than 50% reduction in serum monoclonal (M)-protein levels, and nine (39%) attained a minimal response, with a greater than 25% decrease in serum M-protein levels. No decrease in the size of soft tissue plasmacytomas was observed in six patients with extramedullary involvement.

Adult↗
PubMed2000

[High-dose melphalan treatment followed by hematopoietic progenitor cell rescue in primary amyloidosis].

BACKGROUND: Primary systemic amyloidosis (AL) is a plasma cell dyscrasia characterized by the extracellular deposition of immunoglobulins light chains in different organs and systems. Median survival with current standard treatment is less than 2 years. Intensive chemotherapy followed by hematopoietic stem cell rescue has been used in AL for the last five years. The reported results are encouraging, with a high response rate (65%). Nonetheless, this procedure is associated to an important toxicity, with high transplant related mortality (about 25%). In patients with advanced AL (more than two involved organs) and/or complicated cardiac disease, the mortality is particularly high. In the current report we describe the outcome of the first five patients who received high dose therapy for AL at our institution. PATIENTS AND METHODS: This treatment was administered to patients up to the age of 70 years, who met the standard eligibility criteria for an autologous bone marrow transplantation. Intensive treatment consisted of melphalan 200 mg/m2 in all patients but one who received 140 mg/m2. RESULTS: Two patients died during the first month after the transplant (arrhythmia: 1, multiorganic failure: 1). Both patients had a poor performance status and advanced disease, with more than two organs involved. The response in the remaining three was of stabilization of the nephrotic syndrome in one and objective response in all the involved organs in the remaining two. CONCLUSIONS: High dose therapy (HDT) with stem cell rescue in AL produces a high response rate. Nevertheless, this treatment approach is associated to a high toxicity.

Adult↗
PubMed2000

Blood stem cells compared with bone marrow as a source of hematopoietic cells for allogeneic transplantation. IBMTR Histocompatibility and Stem Cell Sources Working Committee and the European Group for Blood and Marrow Transplantation (EBMT).

Peripheral blood cells are increasingly used in place of bone marrow as a source of hematopoietic stem cells for allogeneic transplantation. The relative efficacy of these 2 approaches is unknown. This retrospective multivariate analysis compared results of 288 HLA-identical sibling blood stem cell transplantations with results of 536 HLA-identical sibling bone marrow transplantations. No transplants were T-cell depleted. Median follow-up was 12 months, and analyses focused on 1-year outcomes. Recipients of blood stem cell transplants had more rapid recovery of neutrophils to at least 0.5 x 10(9)/L (median time to recovery, 14 days, compared with 19 days for marrow transplants; P <.001) and of platelets to at least 20 x 10(9)/L (median time, 18 days, compared with 25 days for marrow transplants; P <.001). There was no significant difference in the incidence of grades II to IV acute graft versus host disease (GVHD). The incidence of chronic GVHD was significantly higher after blood stem cell transplantation (1-year probability [95% confidence interval], 65% [56%-72%] compared with 53% [47%-59%]; P =.02) Relapse incidence in the 2 transplant groups did not differ significantly. Treatment-related mortality rates were lower and leukemia-free survival rates were higher with blood stem cell transplants in patients with advanced leukemia (acute leukemia in second remission or chronic myelogenous leukemia in accelerated phase) but not in early leukemia (acute leukemia in first remission or chronic myelogenous leukemia in chronic phase). The median time from transplantation to hospital discharge was 23 days after blood stem cell transplantation and 28 days after bone marrow transplantation (P =.003). Further study with longer follow-up is necessary to definitively establish the role of blood stem cells for allogeneic transplantation, especially in patients with good-risk disease. (Blood. 2000;95:3702-3709)

Acute Disease↗
PubMed2000

Hybrid chemotherapy consisting of cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine (C-MOPP/ABV) as first-line treatment for patients with advanced Hodgkin disease.

BACKGROUND: Combination chemotherapy, including hybrid regimens, is the standard treatment for patients with advanced Hodgkin disease (HD). Although a prolonged complete response (CR) is achieved in up to 70-80% of patients, long term complications, such as secondary leukemia, are of concern. Cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine (C-MOPP/ABV) is a hybrid chemotherapy in which cyclophosphamide is substituted for mechlorethamine, an agent that has been implicated as the cause of secondary malignancies. METHODS: Seventy-three patients (37 males and 36 females; median age, 35 years) diagnosed with Stage III or IV HD or Stage II with bulky disease, B-symptoms, elevated erythrocyte sedimentation rate, or hilar adenopathy were treated with 8 courses of C-MOPP/ABV at a single institution during a 6-year period. Radiotherapy (RT) was administered when bulky disease or residual masses were present. Endpoints of the study were response to therapy, failure free survival (FFS), overall survival (OS), and toxicity. RESULTS: Sixty-five patients (90%) received the 8 planned courses, with 49 of them (70%) receiving the full prescribed doses. After chemotherapy, 57 patients (78%) reached CR. Seven additional patients who achieved partial response (PR) reached CR after complementary radiotherapy, with an overall CR rate of 88%. The median follow-up was 31 months. Twelve patients relapsed; the 4-year FFS was 66% (95% CI, 54-78%). Two patients died during treatment because of sepsis and four due to disease progression. The 4-year OS was 92% (95% CI, 86-98%). Age > 60 years and bone marrow involvement were related to severe infectious complications. No late toxicity was reported. CONCLUSIONS: C-MOPP/ABV induces CR with acceptable toxicity in a high proportion of advanced HD patients.

Adult↗
PubMed2000

cdc25a and the splicing variant cdc25b2, but not cdc25B1, -B3 or -C, are over-expressed in aggressive human non-Hodgkin's lymphomas.

cdc25 is a family of phosphatases that activate the cyclin-dependent kinases at different points of the cell cycle. cdc25A and -B, but not -C, have been shown to have oncogenic potential. Three different splicing variants of the cdc25B gene, cdc25B1, -B2 and -B3, have also been identified. Experimental studies suggest that cdc25B2 may be more active in vivo than cdc25B3 and -B1, but the relative expression of these splicing variants in human tumors is not known. In this study, we have analyzed the expression of cdc25A, -B1, -B2, -B3 and -C mRNA in 9 non-neoplastic lymphoid samples, 89 non-Hodgki&ngrave;s lymphomas and 9 hematological cancer cell lines by semi-quantitative RT-PCR. cdc25A, -B and -C protein expression was examined by Western blot. Normal peripheral blood lymphocytes and reactive tissues expressed cdc25B1 and -B3 mRNA and very low or undetectable levels of cdc25A, -B2 and -C. High levels of cdc25A and cdc25B2 were found in 35% and 39% of the tumors, respectively, and they were more frequently observed in aggressive than in indolent lymphomas. cdc25B1 and -B3 splice variants were detected in virtually all tumors, and no significant differences were found between high- and low-grade lymphomas. cdc25A and -B protein expression was also higher in aggressive than in indolent lymphomas. cdc25C expression was relatively low in virtually all cases. In conclusion, these findings suggest that cdc25A and -B2, but not cdc25B1, -B3 and -C, are over-expressed in a relatively large number of malignant lymphomas and may participate in the pathogenesis of aggressive variants.

Blotting, Western↗
PubMed2000

Deoxycoformycin in the treatment of patients with hairy cell leukemia: results of a Spanish collaborative study of 80 patients.

BACKGROUND: Deoxycoformycin (DCF) has been reported to produce high response rates in patients with hairy cell leukemia (HCL), but to the authors' knowledge data regarding experience with such therapy in a large HCL series are scarce. METHODS: Between 1988-1997, DCF (4 mg/m(2)/day, every 2 weeks) was administered to 80 HCL patients in 32 Spanish institutions. In 35 of 78 evaluable patients DCF was the first-line therapy; the remaining 43 patients had received other therapies. Pretreatment variables influencing the achievement of complete remission (CR) and event free survival were identified by multivariate analyses. RESULTS: The median number of cycles administered was 7 (range, 1-22 cycles). A CR was obtained in 56 patients (72%) and a partial remission was obtained in 13 patients, for an overall response rate of 88%. In the multivariate analysis previous splenectomy and an Eastern Cooperative Oncology Group (ECOG) performance status > or = 2 were the parameters adversely influencing CR achievement. With a median follow-up of 31.2 months (range, 0.4-126.5 months), disease recurrence was observed in 11 of the CR patients, 5 of whom showed a further response to DCF. An ECOG performance status > or = 2 was the only pretreatment variable associated with a shorter event free survival. Seven patients died, four during the treatment period. The actuarial median event free survival was 46 months (95% confidence interval, 22.5-69.5 months), and 48.7% of the 56 patients who achieved a CR were expected to be alive and disease free at 5 years. Hematologic toxicity (marked neutropenia [22 cases], anemia [6 cases], and thrombocytopenia [1 case]) was the main side effect, followed by nausea and emesis (5 cases); 14 patients required hospitalization. CONCLUSIONS: The results of the current study confirm the effectiveness and acceptable toxicity of DCF in the treatment of patients with HCL.

Aged↗
PubMed2000

Progressive multifocal leukoencephalopathy following oral fludarabine treatment of chronic lymphocytic leukemia.

Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating disorder of the central nervous system usually affecting immunocompromised individuals and is due to infection of the oligodendrocytes by the JC virus. A case of PML in a chronic lymphocytic leukemia (CLL) patient treated with fludarabine is reported, representing the second such instance in which the diagnosis of the neurological disorder was established by brain biopsy. A 61-year-old man with a 14-year history of B-cell type CLL, for which he had received chlorambucil therapy 10 years earlier, developed progressive paresis of both left extremities at 7 months of receiving low doses of oral fludarabine, when his CD4 count has decreased to 0.08 x 10(9)/l. Cranial magnetic resonance imaging revealed a subcortical focal lesion at the right precentral gyrus and a focal lesion at the right thalamus, and a stereotactic brain biopsy showed pathological findings consistent with PML, namely severe myelin breakdown, reactive astrocytosis, and abnormal, huge glial cells with large bizarre nuclei showing granular basophilic inclusions, whereas the presence of the JC virus was demonstrated by in situ hybridization. The present case, in addition to a few previously reported, calls attention to the possibility that severe neurological side effects can be associated with the immunosuppression provoked by the use of fludarabine in CLL patients.

Administration, Oral↗
PubMed2000

INK4a/ARF locus alterations in human non-Hodgkin's lymphomas mainly occur in tumors with wild-type p53 gene.

INK4a/ARF locus codes for two different proteins, p16(INK4a) and p14(ARF), involved in cell cycle regulation. p14(ARF) is considered an upstream regulator of p53 function. To determine the role of these genes in the pathogenesis of human non-Hodgkin's lymphomas we have analyzed exon 1beta, 1alpha, and 2 of the INK4a/ARF locus and p53 gene aberrations in 97 tumors previously characterized for p16(INK4a) alterations. p53 alterations were detected in four of 51 (8%) indolent lymphomas but in 15 of 46 (33%) aggressive tumors. Inactivation of p14(ARF) was always associated with p16(INK4a) alterations. Exon 1beta was concomitantly deleted with exon 1alpha and 2 in eight tumors. One additional lymphoblastic lymphoma showed deletion of exon 1alpha and 2 but retained exon 1beta. No mutations were detected in exon 1alpha and 1beta in any case. Two of the three mutations detected in exon 2 caused a nonsense mutation in the p16(INK4a) reading frame and a missense mutation in the ARF reading frame involving the nucleolar transport domain of the protein. The third mutation was a missense mutation in the p16(INK4a) reading frame, but it was outside the coding region of p14(ARF). Aggressive lymphomas with p14(ARF) inactivation and p53 wild type showed a significantly lower p53 protein expression than tumors with no alteration in any of these genes. In this series of tumors, inactivation of the INK4a/ARF locus mainly occurred in tumors with a wild-type p53 gene because only two lymphomas showed simultaneous aberrations in these genes. Tumors with concomitant alterations of p16(INK4a) and p14(ARF)/p53 genes seem to exhibit a worse clinical behavior than lymphomas with no alterations or isolated inactivation of any of these genes. These findings indicate that p14(ARF) genetic alterations occur in a subset of aggressive NHLs, but they are always associated with p16(INK4a) aberrations. Concomitant disruption of p16(INK4a) and p14(ARF)/p53 regulatory pathways may have a cooperative effect in the progression of these tumors.

Carrier Proteins↗
PubMed2000

Assessment of peripheral blood lymphocyte subsets in idiopathic myelofibrosis.

The objective of this study was to contribute to a better characterization of the immunological profile of idiopathic myelofibrosis (IM) at presentation by analysing the blood lymphocyte subsets and their possible correlations with other disease features. Absolute blood lymphocytes and lymphocyte subsets were assessed in 31 IM patients, compared with those from 34 healthy individuals, and correlated with the patients' main clinical, hematological and bone marrow histologic features. The mean lymphocyte count of the IM patients was 1.1 (SD 0.6) x 10(9)/L, versus 1.6 (SD 0.49) x 10(9)/L in controls (p = 0.0006), with 24 of the 31 patients (77.4%) showing lymphocytopenia (< 1.5 x 10(9)/L). IM patients had significantly lower counts of CD3, CD4, CD8, and CD3 -/ CD56+ cells, and significantly higher CD3 +/CD56 + lymphocyte counts. Although no significant differences were found between patients and controls with regard to CD19+/CD5+ cell counts, increased CD5 + B-cell lymphocytes were observed in three IM patients. In one of the latter patients, Ig gene rearrangement analysis of the heavy chain gene demonstrated such a subpopulation to be clonal, but the patient did not develop features of chronic lymphoid leukemia during a 5-yr follow-up. No correlation was found between the patients' blood lymphocyte counts and other disease features. We conclude that most IM patients have absolute lymphopenia, decreased T cells and increased cytotoxic T cells at diagnosis, and 10% of them show an increased CD5 + B-cell subpopulation.

Adult↗
PubMed2000

Patients with mantle-cell lymphoma relapsing after autologous stem cell transplantation may be rescued by allogeneic transplantation.

Two patients with disseminated mantle-cell lymphoma relapsed 24 and 13 months, respectively, after high-dose chemotherapy and autologous stem cell transplantation (autoSCT). Both patients had an HLA-identical sibling and received an allogeneic stem cell transplant (alloSCT) 32 and 18 months after autologous transplant, after conditioning with fractionated 12 Gy total body irradiation plus cyclophosphamide 120 mg/kg. They are both alive and in complete remission 24 months after transplant. Both patients have developed chronic graft-versus-host disease and their Karnofsky performance status is 90%. AlloSCT may offer a useful approach in a subgroup of patients with mantle-cell lymphoma who have relapsed after autologous transplantation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Complete remission of idiopathic myelofibrosis following donor lymphocyte infusion after failure of allogeneic transplantation: demonstration of a graft-versus-myelofibrosis effect.

A patient with idiopathic myelofibrosis (IM) in the osteosclerotic phase received an allogeneic stem cell transplant. Hemopoietic engraftment was rapid, and full donor chimerism was observed on day +70. However, a few months later, replacement of donor hemopoiesis by the patient's 20q- cell clone was observed, followed by reappearance of the blood IM features, marrow fibrosis and osteosclerosis. At 8 months from transplant donor lymphocytes were infused, which induced chronic GVHD. This resulted in normalization of the blood, with disappearance of the fibrosis and osteosclerosis, effects which persisted 20 months later. This case provides evidence for a graft-versus-disease effect in IM.

Female↗
PubMed2000

High-dose therapy autotransplantation/intensification vs continued standard chemotherapy in multiple myeloma in first remission. Results of a non-randomized study from a single institution.

The purpose of this study was to analyze the outcome of patients with multiple myeloma (MM) responding to initial chemotherapy who received intensification with high-dose therapy/autotransplantation (HDT) as compared to that of those who were continued on standard chemotherapy. From 1 January 1990 to 30 June 1998, 64 patients with MM who were younger than 65 years achieved a response to initial chemotherapy. Due to referral reasons, patients preference or inclusion in trials, 31 patients received HDT as early intensification while 33 were continued on standard chemotherapy. The presenting features were similar in both groups, except for the median age, which was lower in the HDT group (53 vs 58 years, P = 0.007). Complete response negative immunofixation - (CR) was achieved in 12 of 31 (39%) patients intensified with HDT and in two of 33 (6%) patients who were continued on conventional chemotherapy (P = 0.002). Event-free survival (EFS) was significantly longer in the HDT group (median, 43 vs 21 months; P = 0.007). Overall survival (OS) was not significantly different between groups (median, 62 vs 38 months; P = 0.21). However, patients in the HDT group who achieved CR had an EFS (median, 51 vs 31 months; P = 0.03) as well as an OS (median, not reached vs 50 months; P = 0.0006) significantly longer than those achieving a lower degree of response. In conclusion, this non-randomized study shows that early HDT increases CR rate and prolongs EFS. In addition, these results highlight CR as a crucial step for achieving long-lasting disease control and prolonged survival in patients with MM.

Adult↗
PubMed2000

Rapid diagnosis of acute promyelocytic leukemia by analyzing the immunocytochemical pattern of the PML protein with the monoclonal antibody PG-M3.

The fusion protein, promyelocytic leukemia-retinoic acid receptor (PML-RAR)alpha, generated by the t(15;17) translocation has an abnormal cellular distribution with colocalization of RARalpha and PML proteins. We analyzed the immunostaining pattern of PML protein using the PG-M3 monoclonal antibody directed against the amino terminal portion of PML (retained in wild-type PML and PML-RARalpha fusion protein) in the diagnosis of acute promyelocytic leukemia (APL). In addition, we compared this test with other methods for detecting the PML-RARalpha fusion gene. A normal immunostaining pattern was observed in nonmyeloid disorders and in 78 of 111 acute myeloid leukemias (AMLs). A microgranular pattern was observed in 25 AMLs, all corresponding to APL. These results were concordant with the reverse transcriptase-polymerase chain reaction results for PML-RARalpha fusion gene. Only 1 case positive for the PML-RARalpha transcript showed a normal protein pattern by immunocytochemistry. PML immunostaining was helpful to rapidly differentiate 7 cases with borderline characteristics and to obtain the diagnosis in 2 cases with scarce material. The effectiveness and low cost of this technique support its routine use as a first-line procedure in the differential diagnosis of AML.

Antibodies, Monoclonal↗