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E Matutes

Publications and source records attributed to E Matutes.

At least 181 records · Page 10Linked to original sources

Aberrant rearrangements within the immunoglobulin heavy chain locus in hairy cell leukemia.

The cell surface expression of multiple immunoglobulin heavy chain (IGH) isotypes, preferentially observed in hairy cell leukemia (HCL), is incompatible with the deletion model of IGH class switching, and alternative models involving RNA-splicing have been proposed. To help discriminate between these possibilities we have examined the configuration of the IGH locus by DNA blot in 38 cases of HCL. Deletion of at least one allele of C mu/C delta was seen in 14 cases (37%). Of 12 cases in which IgG and/or IgA were expressed, three exhibited biallelic deletion of C mu/C delta compatible with deletional class-switching whereas the remaining 9 cases retained both alleles of C mu/C delta. These data indicate that both DNA deletion and RNA-splicing mechanisms of class-switching may operate in HCL. In a further 17 cases, other unexpected abnormalities of the IGH locus mapping to the JH-C mu intron in one of two patterns were observed. First, discordance between JH and C mu in BamHI DNA digests was found in 12 cases. Similar patterns were observed in only 4/91 cases of B-cell chronic lymphocytic leukemia and 0/15 of B-cell prolymphocytic leukemia. To preclude chromosomal translocations involving the JH-C mu intron, rearrangements of BCL1, BCL2, BCL3, and MYC were sought in 23 cases but none of the cases showed oncogene rearrangement to the intron. Second, abnormal-sized C mu fragments arising as a consequence of abnormalities of the JH-C mu intron were detected in HindIII, BgIII, and/or Xbal digests in 10/23 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗

The immunophenotype of hairy cell leukemia (HCL). Proposal for a scoring system to distinguish HCL from B-cell disorders with hairy or villous lymphocytes.

We have analysed the immunological profile of cells from 194 patients with a B-cell disorder associated with circulating hairy or villous lymphocytes. These included: 69 typical HCL, 25 HCL-variant and 100 splenic lymphoma with villous lymphocytes (SLVL). All cases were HLA-DR+, CD19+, CD2- and most expressed Smlg with light chain restriction. The kappa/lambda ratios were: HCL, 1.2; SLVL, 1.5; and HCL-variant, 0.55. The majority were FMC7+ (89-96% of cases) and membrane CD22+ (73-98% of cases) and often negative with CD5 and CD23, markers characteristic of chronic lymphocytic leukemia. CD24 was variably expressed ranging from 21% of cases in HCL-variant to 60% in HCL and 89% in SLVL; CD10 and CD38 were positive in one third of SLVL but usually negative in HCL and HCL-variant. Of the four markers considered typical of HCL, CD11c, CD25, HC2 and B-ly-7, CD25 and HC2 were consistently negative in HCL-variant and a minority of SLVL cases expressed CD25 or HC2+ or B-ly-7+; CD11c was positive in all three disorders (47 to 97% of cases). Based on the most common phenotype of typical HCL: CD11c+, CD25+, HC2+ and B-ly-7+, we propose a scoring system which considers the reactivity with each of these four markers and gives 1 point if positive and 0 points if negative. Scores range from 4 (typical of HCL) to 0 (atypical of HCL). 98% of HCL had high scores (3 or 4) whereas 88% of HCL-variant and 77% of SLVL scored 1 or 2 and no single case scored 3 or 4.(ABSTRACT TRUNCATED AT 250 WORDS)

B-Lymphocytes↗

Incidence and significance of abdominal lymphadenopathy in hairy cell leukaemia.

We have investigated the incidence and significance of abdominal lymphadenopathy in hairy cell leukemia (HCL) by routinely CT scanning 88 patients. These included 70 men and 18 women with a median age of 51 years (range 25-83). Abdominal CT scans were performed at diagnosis in 29 patients and in 59 during the course of the disease. Abdominal lymphadenopathy was documented in 25 patients (28%) overall; the incidence of abdominal lymphadenopathy was higher in relapse (56%) than at diagnosis (17%). All patients with lymphadenopathy had bone marrow disease. There is no association with age or sex but lymphadenopathy tends to be more common in patients with long-standing disease (median duration of disease 6 years v one year in those without nodes) and in patients with bulky disease, particularly in the relapse group (splenomegaly/splenectomy in 95% vs 40%). The presence of abdominal nodes is also associated with relative resistance to treatment, with more treatment failures and fewer complete responses seen in this group. Most patients with lymphadenopathy had large, immature-looking hairy cells present in both the bone marrow and lymph nodes, when these were examined. Abdominal lymphadenopathy in HCL is more common than previously recognised, particularly in relapsed patients, and is always associated with active disease. The presence of large hairy cells and the relative resistance to treatment suggest that this phenomenon represents a form of transformation of the disease. Longer follow up is required to confirm this.

Abdomen↗

HTLV-I positive adult T-cell leukaemia/lymphoma (ATLL) in Chile.

We describe the clinical and laboratory features of nine patients born in Chile with HTLV-I-positive adult T-cell leukemia/lymphoma (ATLL). All were adults (median age 51 years) of Caucasian origin without evidence of Indian or foreign extraction and none had been out of the country. The main disease features were organomegaly, cutaneous lesions, hypercalcemia and leukemia with atypical polylobed lymphocytes displaying a CD2+, CD3+, CD4+, CD8-, CD7- T-cell phenotype. Eight patients presented with acute type ATLL and one had a chronic form lasting for 16 months prior to the development of the acute phase. Lymph node histology (three cases) was consistent with a T-cell non-Hodgkin's lymphoma (large and small cells). Antibodies to HTLV-I were detected by ELISA and particle agglutination in the serum from eight of nine patients. DNA analysis showed HTLV-I proviral DNA in all seven cases investigated, including the single serologically negative patient. In five cases, HTLV-I was monoclonally integrated and in one case oligoclonal. In the seventh case viral DNA clonal status was ambiguous. Response to therapy was poor and median survival was 3 months (range 2-20 months). This study provides further evidence that HTLV-I is endemic in Chile, a non-tropical country where the two main diseases associated with HTLV-I, ATLL and TSP, are found.

Adult↗

Neonatal mixed lineage acute leukaemia.

We report here an uncommon case of neonatal acute leukaemia that presented concomitant with serological evidence of rubella infection. The clinical course was aggressive and the patient died 5 days after diagnosis from septicaemia. Leukaemic blasts had a mixed lineage immunophenotype co-expressing a constellation of B-lymphoid (CD19, cytCD22, TdT) and myeloid (CD13, CD33, CD14, anti-MPO) markers, as well as multiple adhesion molecules and markers associated with early lympho-myeloid progenitor cells (CD34, CD7, HLA-DR). A previously unrecorded discordant expression of different CD10 and CD34 epitopes was identified using different monoclonal antibodies. The karyotype was 46,XX t(4;11)(q21;q23) and molecular analysis confirmed rearrangement of the trithorax-related oncogene HRX at 11q23. There was a clonal biallelic rearrangement of the immunoglobulin heavy-chain gene. The features of this rare case have implications for possible aetiological events leading to leukaemia.

Acute Disease↗

mb-1: a new marker for B-lineage lymphoblastic leukemia.

The expression of the Ig-linked mb-1 polypeptide was analyzed by immunocytochemistry (alkaline phosphatase anti-alkaline phosphatase technique) using a specific monoclonal antibody in 165 cases of acute leukemia, with 88 being lymphoblastic (ALL) and 77 myeloid (AML). The purpose of the study was to investigate the specificity of this reagent for B-lineage cases and its reactivity on leukemias that coexpress myeloid and B-cell antigens (biphenotypic). The majority (89%) of 72 B-cell precursor ALL patients were positive. Of these, mb-1 was expressed in all 9 patients with early-B-ALL (CD10-, c mu-), in all 11 patients with pre-B-ALL (c mu+) and in the single case of B-ALL (smIgM+). Forty-three of 51 patients with common-ALL (CD10+, c mu+) were also positive. All 16 T-lineage ALL patients and 72 (93.5%) of the AML patients examined were mb-1 negative. Four of the 5 mb-1-positive AML patients were considered biphenotypic and expressed other B-cell antigens such as CD10, CD19, and/or cCD22 and all showed rearrangement of the Ig heavy chain genes. Within the AML cases, mb-1 and cCD22 were more useful than other B-cell antigens in detecting biphenotypic cases, and mb-1 showed the highest correlation with the clonal rearrangement of Ig heavy chain genes. These results indicate that mb-1 is a sensitive and specific reagent for B-lineage blasts that will aid in the classification of B-cell precursor ALL and in the identification of biphenotypic leukemia presenting as AML.

Antibodies, Monoclonal↗

Trisomy 12 in chronic lymphocytic leukemia detected by fluorescence in situ hybridization: analysis by stage, immunophenotype, and morphology.

Fluorescence in situ hybridization (FISH) with a chromosome 12 specific alpha-centromeric probe was performed on interphase cells from 183 patients with B-cell chronic lymphocytic leukemia (CLL). Twenty one cases with trisomy 12 (11.5%) were detected. The number of trisomic cells ranged from 5.5% to 76% (mean 38.5%). No correlation was found between the presence of trisomy 12 and white blood cell count, hemoglobin level, platelet count, a specific immunophenotype, clinical stage, sex, splenomegaly, or lymphadenopathy. Morphologic review of all cases with trisomy 12 showed seven (33%) with more than 10% prolymphocytes and three (14%) with CLL of mixed cell type. While trisomy 12 is the most common chromosomal abnormality in CLL, it is more frequent in morphologically atypical cases, some of which may be undergoing transformation. There was a statistically significant difference in the incidence of atypical cases between those with (47%) and without (7.6%) trisomy 12 (P < .001). It remains to be determined whether this abnormality is associated with a worse prognosis; this is currently being investigated in the context of a national therapeutic trial. The technique used is more sensitive than conventional cytogenetic analysis, which in this series failed to detect trisomy 12 in six cases. FISH allows the systematic study on a large number of patients without the need of metaphase preparations.

Antigens, CD↗

Cytogenetic studies in splenic lymphoma with villous lymphocytes.

We report the cytogenetic findings on 31 cases of splenic lymphoma with villous lymphocytes (SLVL). TPA stimulated cells from peripheral blood (28 cases), spleen (two cases) and lymph node (one case) with SLVL have been analysed. A clonal chromosome abnormality was found in 27/31 patients (87%); this was identified as a simple abnormality in 12 cases and a complex one in 15. Four recurring abnormalities were seen: t(11;14)(q13;q32) in five patients, deletions or translocations involving 7q in seven patients, iso 17q in four patients and translocations involving 2p11 in four patients. The high frequency of clonal chromosome abnormalities in SLVL contrasts with the usually benign clinical course of this disease. Abnormalities found frequently in patients with chronic lymphocytic leukaemia (CLL) such as trisomy 12 and deletions or translocations involving 13q14 were each seen in only one patient. No case had the t(14;18) characteristic of follicular lymphoma. Our findings demonstrate the high frequency of clonal and often complex chromosome abnormalities in SLVL. Although a unique chromosome rearrangement has not been identified, a pattern of four recurrent abnormalities has emerged. Our results suggest that SLVL is distinct on cytogenetic grounds from B-CLL and follicular lymphoma but shows similarity with mantle cell lymphoma, lymphoplasmacytic lymphoma and B-PLL.

Adult↗

Immunological and ultrastructural studies in acute biphenotypic leukaemia.

AIMS: To compare the sensitivity of the ultrastructural method to detect myeloperoxidase (MPO) with light microscopy and immunocytochemistry using an anti-MPO antibody; to examine the expression of lymphoid antigens in relation to MPO activity in blast cells from cases of biphenotypic leukaemia. METHODS: Blast cells from 14 cases of biphenotypic acute leukaemia were analysed. Immunological markers were performed by single or double immunofluorescence staining on a flow cytometer. The presence of MPO was determined by light microscopy, electron microscopy on fixed and unfixed cells, and by immunoalkaline phosphatase with an anti-MPO antibody. The immunogold method was applied at the ultrastructural level to assess the expression of lymphoid and myeloid antigens at the same time as the MPO activity. RESULTS: Six of the 14 cases were initially classified as acute lymphoblastic leukaemia (ALL) and eight as acute myeloid leukaemia (AML). MPO activity was shown at the ultrastructural level in 4-99% blasts from all cases. Six of the 14 were MPO negative by light microscopy and three of these were negative with the antibody anti-MPO. Coexpression of lymphoid antigens (CD19, CD10, or CD2) and MPO was shown by the immunogold method in four out of 11 cases; in seven cases the blasts coexpressed myeloid antigens (CD13, CD33) and MPO. CONCLUSIONS: Electron microscopy is more sensitive for showing MPO than light microscopy and immunocytochemistry; the immunogold method combined with MPO used at the ultrastructural level can help to define the cell lineage involved in biphenotypic leukaemia by highlighting the myeloid component defined by MPO.

Acute Disease↗

Splenectomy in lymphoproliferative disorders: a report on 70 cases and review of the literature.

Between February, 1970 and September, 1991, we performed splenectomies on 70 patients with chronic lymphoproliferative disorders including primary leukemias: 19 B-cell chronic lymphocytic leukemia, 1 B-cell prolymphocytic leukemia, 22 hairy cell leukemias, 4 large granular lymphocytic leukemias, 1 T-cell prolymphocytic leukemia, and non-Hodgkin's lymphomas (NHL): 10 splenic lymphomas with villous lymphocytes, 4 follicular lymphomas, 5 mantle cell lymphomas, 3 lymphoplasmacytic and 1 large cell NHL. The primary indications for surgery in this series were therapy-resistant disease (40%) and therapeutic splenectomy (38%). Postsplenectomy, 70% of patients had a complete hematological response, 23% had a partial response, and 7% were nonresponsive. Median treatment-free survival correlated with the hematologic response postsplenectomy and the underlying diagnosis. Better treatment-free survivals were seen in patients with lesser degrees of anemia and thrombocytopenia. Overall, improvements were more pronounced in the B-cell than in the T-cell disorders. Indications for further therapy, postoperative morbidity and mortality, and survival times are discussed along with a review of the literature. These findings advocate a continuing role for splenectomy in symptomatic lymphoid malignancies running with splenomegaly and hypersplenism.

Adult↗

Immunophenotypic characteristics of blast crisis of chronic myeloid leukaemia: correlations with clinico-biological features and survival.

Blast cells from 40 patients with Philadelphia-positive chronic myeloid leukaemia (CML) in blast crisis were analysed by immunophenotypic methods. In 27 cases, BCR gene studies were also performed. By light microscopy morphology and cytochemistry the cases were classified as follows: undifferentiated (n = 7; 17.5%), myeloid (n = 27; 67.5%), and lymphoid (n = 6; 15%). On the basis of the immunological markers, the cases were reclassified as: myeloid (n = 17; 42.5%), megakaryoblastic (n = 17; 42.5%), and lymphoid (n = 6; 15%). The seven cases initially considered as undifferentiated by morphological and conventional cytochemical criteria were classified as myeloid (four cases) and megakaryoblastic (three cases) by marker analysis. The monoclonal antibody anti-myeloperoxidase (anti-MPO) was the most sensitive myeloid associated marker in these cases, being positive in five of them. A significant proportion (27%) of non-lymphoid blast crisis cases were CD7-positive, and myeloid markers were positive in the four lymphoid CML-CB cases studied. Analysis of the clinico-haematological characteristics on the various subgroups of patients showed that patients with lymphoid blast crisis had shorter duration of the chronic phase, more frequent extramedullary blastic involvement, more favourable response to therapy, and longer survival. Finally, a trend for an association between megakaryoblastic involvement of blast crisis and breakpoint localization in the 3' extreme of the M-bcr segment was also noted.

Adolescent↗

Lineage commitment in biphenotypic acute leukemia.

Acute leukemias (ALs) with phenotypic and genotypic features of several hematopoietic lineages are difficult to classify and may represent the transformation of multipotent stem cells. We have studied immunological features of 200 cases of acute leukemia (109 acute myelogenous leukemia, AML, and 91 acute lymphoblastic leukemia, ALL, according to FAB criteria), including 17 (8.5%) classified as biphenotypic by a scoring system based on the number and specificity of unexpected lineage antigens and which gives more weight to cytoplasmic markers such as myeloperoxidase, CD3, and CD22, and less to other membrane markers. Sixty-eight AML and 42 ALL cases were also examined for rearrangements of the immunoglobulin (Ig) and T-cell receptor (TCR) beta, gamma, and delta genes, and these included 12 biphenotypic AL. The expression of myeloid antigens in ALL was seen in 25% of the cases. All B-lineage ALL had rearrangements and/or deletions of the Ig genes whereas TCR beta, gamma, and delta genes were rearranged in 21%, 52%, and 71%, respectively. TCR delta, gamma and/or beta were rearranged in T-ALL and four out of 13 cases had Ig gene rearrangement. Lymphoid-associated antigens were expressed in 40% of AML cases; those most frequent expressed were CD7 (17%), CD2 (15%), CD19 (10%), and CD10 (7.5%). Evidence of Ig and/or TCR gene rearrangements was detected in 12% of AML cases. There was no correlation between the isolated expression of terminal deoxynucleotidyl transferase (TdT), B, and T-cell antigens with Ig and TCR gene rearrangements. However, in cases of AML defined as biphenotypic because they expressed two or more lymphoid antigens there was a statistically significant correlation between gene rearrangements and lymphoid score (p < 0.001). Our findings support the concept of biphenotypic leukemia as a distinct entity in which there is frequent correspondence between phenotypic and genotypic changes.

Acute Disease↗