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E Matutes

Publications and source records attributed to E Matutes.

At least 199 records · Page 11Linked to original sources

[Molecular genetics in the diagnosis of acute leukemia and chronic lymphoproliferative syndromes in 121 cases].

BACKGROUND: The introduction of biology and molecular genetics in the hematological laboratory has brought about a new and spectacular advance in the study of cloning and cytological characterization of malignant hemopathies. The principal aim of the present study was to analyze the contribution of this new technology in the diagnosis of acute leukemia (AL) and chronic lymphoproliferative syndromes (CLS) through analysis of lymphoid clonality and genetic rearrangement proper to the lymphoid differentiation of the B and T cells. METHODS: The genetic rearrangement of the heavy chain immunoglobulins (IgH) and the beta (beta) and gamma (gamma) chains of the T receptor (TRC) in 121 patients with the following malignant hemopathies: acute myeloid leukemia (AML), 28 cases; acute lymphoblastic leukemia (ALL), 27 cases; and CLS, 66 cases. The Southern method was used. RESULTS: Clonality analysis: presence of genetic rearrangement (clonality) in all the cases of lymphoblastic AL (ALL) and CLS and in 5 of 28 cases of AML (3 IgH and 2 TRC). Strain analysis: presence of absolute coincidence (exclusive rearrangement of the IgH or TRC genes in proliferations of the B or T strain, respectively) in 18 of 27 cases (67%) of ALL, in 14 of 15 cases (93%) of T-CLS and in all cases (100%) of B-CLS. CONCLUSIONS: In malignant hemopathies the analysis of genetic rearrangement constitutes a method of great practical use for determining the presence of lymphoid clonality and is a good complement to conventional morphological and immunophenotypic procedures for cytological characterization of the same.

Acute Disease↗

Translocation t(11;14)(q13;q32) in chronic lymphoid disorders.

The translocation t(11;14)(q13;q32) has been described in a spectrum of B-lymphoproliferative diseases and involves a putative oncogene, BCL1, which maps to chromosome band 11q13. Recent evidence indicates that this abnormality may delineate particular subtypes of lymphoma, such as intermediate lymphocytic and centrocytic lymphomas. Thus the possible significance of the t(11;14) within B-cell disorders should be reexamined in the light of a more objective approach to classifying these diseases by morphology, histology, and immunophenotype. We describe 16 patients with t(11;14)(q13;q32) from a series of 90 patients with chronic lymphoid disorders in whom clonal chromosome abnormalities were detected. All the cases were leukemic: prolymphocytic (B-PLL; 4/15 cases), chronic lymphocytic leukemia (CLL) with increase in prolymphocytes (2/9 cases), or non-Hodgkin lymphoma in leukemic phase, intermediate (3/4 cases), lymphoplasmacytic (2/2 cases), splenic lymphoma with villous lymphocytes (4/18 cases), and follicular (1 case). None of the CLL (25) or hairy cell leukemia cases (15) had t(11;14). Our findings showed that t(11;14) occurred in leukemias of mature B cells with lymphoplasmacytic features as judged by morphology and immunophenotype.

Adult↗

The role of an anti-myeloperoxidase antibody in the diagnosis and classification of acute leukaemia: a comparison with light and electron microscopy cytochemistry.

The enzyme myeloperoxidase (MPO) is the hallmark of the myeloid lineage. We have analysed the presence of MPO in blasts from 180 cases of acute leukaemia (103 acute myeloid leukaemia (AML) and 77 acute lymphoid leukaemia (ALL) by means of monoclonal antibodies anti-MPO and immunocytochemistry (alkaline phosphatase anti-alkaline phosphatase method). The aim of the study was to investigate the specificity and sensitivity of this marker compared with MPO cytochemistry by light (LM) and electron microscopy (EM), and with the expression of myeloid antigens. Anti-MPO was positive (greater than 3% blasts) in all but one of the 90 AML positive by LM cytochemistry. Of 13 AML cases negative by MPO cytochemistry, six showed 3-10% blasts reactive with anti-MPO and were also positive with antibodies to CD13 and/or CD33. The presence of MPO was confirmed in four of these by EM. The overall positivity of anti-MPO in AML was 92%. Anti-MPO was negative in all but two ALL (6% and 8% positive blasts). The blasts in these two cases were also CD13, CD33 and MPO positive by EM; both were thus reclassified as biphenotypic. Another two ALL reinterpreted as biphenotypic were negative by MPO cytochemistry and anti-MPO but were MPO positive by EM and with CD13 and/or CD33. We conclude that anti-MPO is a sensitive and specific early marker of myeloid blasts and should be incorporated in the routine immunophenotyping of acute leukaemia.

Acute Disease↗

Massive abdominal lymphadenopathy in hairy cell leukaemia: a report of 12 cases.

Lymphadenopathy is an uncommon finding in hairy cell leukaemia (HCL). We report 12 HCL patients in whom relapse was associated with massive abdominal lymphadenopathy. All but one had long-standing HCL (range 3-25 years; median 10 years); in one it was discovered at presentation. Nine patients had been splenectomized and seven had previously been treated with 2'deoxycoformycin (DCF) and/or alpha-interferon (alpha IFN): three had achieved complete remission and four a partial response. The computerized tomography (CT) scan appearances were similar in all cases with a primary lymph node mass centred around the coeliac axis and involving upper para-aortic and retropancreatic regions. Histology and/or cytology confirmed nodal involvement by HCL in six patients. Large immature hairy cells were seen in both lymph nodes and bone marrow, suggesting a degree of transformation. Nine patients were treated with DCF: one had complete resolution, six responded with 50-90% reduction of the lymphadenopathy, one did not respond and one is still on treatment; alpha-IFN was used concomitantly or sequentially in two of the responders. One responding patient died of sepsis after four injections of DCF. Three patients received either alpha- or beta-IFN alone with no response. One elderly patient was not treated. Abdominal lymphadenopathy could be part of the natural history of HCL and/or may represent a transformation analogous to that seen in other low-grade lymphoproliferative disorders. Routine abdominal CT scanning should be part of the work up of all patients with HCL.

Adult↗

The value of detecting surface and cytoplasmic antigens in acute myeloid leukaemia.

The immunophenotype of leukaemia cells from 60 patients with acute myeloid leukaemia (AML) was analysed with the APAAP technique using a panel of anti-myeloid and lymphoid associated monoclonal antibodies (McAb). Cells from all cases, including three with negative cytochemical features, were labelled by at least one of the anti-myeloid McAb CD13, anti-myeloperoxidase (anti-Mpo), and/or CD14. The most sensitive marker was CD13, since it was positive in 90% of cases. In two out of three AML cases defined as M0-AML, CD13 was expressed in the cytoplasm but not on the membrane; in these three cases peroxidase (Mpo) was not detected by conventional cytochemistry, but could be demonstrated in all of them using the McAb anti-Mpo. The simultaneous expression of CD14 and CD68 McAb was often confined to the M4 and M5 FAB AML subtypes (92% cases) as compared to the others: M1, M2, M3 (18% cases). Lymphoid antigens were rarely positive (TdT+: 13%, CD7+: 15%, CD19+: 5%) and none of the AML cases were CD3+ or CD10+. By contrast, CD4 was expressed in blasts from 44% of cases and this was not restricted to AML with a monocytic component (M4, M5) but also found in other subtypes. There were no significant differences in the clinical or prognostic features according to the positivity or negativity with TdT and CD4. By contrast, expression of CD7 was associated with refractoriness to the treatment or short complete remission duration, although the number of patients is too small to draw firm conclusions. Our findings support the clinical and diagnostic relevance of immunophenotypic studies in AML.

Acute Disease↗

Characterisation of normal peripheral blood cells in cycle identified by monoclonal antibody Ki-67.

AIMS: To investigate the numbers, morphology, and lineage assignment of Ki-67 positive cells in peripheral blood from normal subjects. METHODS: Single and double immunoenzymatic staining procedures, immunoperoxidase, and immunoalkaline phosphatase were used with Ki-67, a monoclonal antibody that recognises a nuclear antigen present in proliferating cells, with markers expressed in B and T lymphocytes and monocytes. RESULTS: In the five healthy donors 2.1% (range 1.6-3.7%) cells of the blood mononuclear fraction and 2.7% (range 2.3-3.9%) lymphocytes were Ki-67 positive. Of these, 88% (range 85-90%) were small cells and 12% (range 10-15%) were medium sized. Forty one per cent of the Ki-67 positive cells were CD3 positive by double immunoenzymatic staining and corresponded to T lymphocytes, and 11.4% were mature B cells expressing kappa or lambda light chains. Monocytes detected by the anti-lysozyme antibody were consistently Ki-67 negative. Half of the Ki-67 positive lymphocytes could not be accounted for by B or T cells with the markers used. Most Ki-67 positive cells were of small size; the B lymphocytes in cycle showed abundant cytoplasm and features suggestive of lymphoplasmacytic differentiation. CONCLUSIONS: The methodology described is useful for the simultaneous detection of nuclear and cytoplasmic antigens. The demonstration that a proportion of normal blood lymphocytes are in cell cycle raises the issue of whether immunophenotypic analysis of Ki-67 positive cells in haemopoietic malignancies with peripheral blood disease should be carried out to define more precisely the proportion of normal and neoplastic cells in cycle.

Adult↗

Expression of Ki-67 nuclear antigen in B and T cell lymphoproliferative disorders.

AIMS: To determine whether the proliferation rates of tumour cells may relate to prognosis and reflect disease activity. METHODS: Blood mononuclear cells from 155 patients with B cell (n = 120) or T cell (n = 35) chronic lymphoproliferative disorders were tested with the monoclonal antibody Ki-67 by indirect immunoperoxidase or immunoalkaline phosphatase techniques. B cell diseases included chronic lymphocytic leukaemia (CLL), CLL in prolymphocytic transformation (CLL/PL), prolymphocytic leukaemia (B-PLL) and non-Hodgkin's lymphoma (B-NHL) in leukaemic phase. The T cell diseases comprised large granular lymphocyte (LGL) leukaemia, T-PLL, and T-NHL. RESULTS: These showed significantly higher proportions of Ki-67 positive cells in T cell (11.2%) than in B cell (2.9%) disorders (p < 0.001). The highest values were found in NHL of both B and T cell types, particularly when low grade disease transformed to high grade. The lowest percentages of Ki-67 positive cells were found in CLL (1.4%) and LGL leukaemia (1.7%); intermediate values were seen in B PLL (3.3%) and T PLL (5.8%). CONCLUSIONS: There is a positive correlation between prognosis and proliferation rates in chronic B and T cell lymphoproliferative disorders. Estimation of Ki-67 in circulating leukaemic cells could be used to determine prognosis in low grade malignancies.

Humans↗

A simplified method of detection of clonal rearrangements of the T-cell receptor-gamma chain gene.

A series of T-cell proliferations in peripheral blood, bone marrow, or tissue samples, together with seven T-cell lines, were analysed for clonality. The technique used employs the polymerase chain reaction (PCR) to amplify rearranged T-cell receptor gamma genes, using primers recognising conserved sequences in the variable and joining gene segments. Of the 20 cases of T-cell leukaemia or lymphoma analysed, a clone was detected in 14 (70%): Of seven T-cell lines, a clone was detected in 6 (84%). No positive results were recorded in eight non-T-cell disorders (including nonlymphoid malignancies and reactive disorders). When the results of this technique were combined with the results of our previously published method for the detection of clonally rearranged T-cell receptor-beta (TCR-beta) genes using PCR, 9 of 10 (90%) T-cell tumours were detected. This method uses only four primer combinations in two tubes, and is therefore simple and rapid: it requires no radiolabelling, uses only a small amount of tissue, and can be performed on formalin-fixed, paraffin-embedded tissue.

Adult↗

Monoclonal antibody Ki-67 identifies B and T cells in cycle in chronic lymphocytic leukemia: correlation with disease activity.

Ki-67 is a monoclonal antibody that recognises a nuclear antigen expressed during most phases of the cell cycle. We have analysed, by immunocytochemistry, the frequency, morphology, and clinical significance of Ki-67+ cells in 108 patients with B-cell chronic lymphocytic leukemia (CLL). Because in normal peripheral blood Ki-67+ cells are mainly T lymphocytes, we have also investigated, by double immunoenzymatic staining, the proportion of Ki-67+ T cells (Ki-67/CD3+) in CLL. Four groups of patients were identified: (i) 47 with stage A, (ii) 32 with stages B + C, (iii) 24 with greater than 10% of circulating prolymphocytes (CLL/PL) and (iv) five with Richter's syndrome. Within stage A CLL, two groups were considered: A' (Hb greater than or equal to 12 g/dl and lymphocytes less than 30 + 10(9)/l) and A" (Hb less than 12 g/dl or lymphocytes greater than or equal to 30 x 10(9)/l). The percentage and absolute number of Ki-67+ leukemic cells was found to increase with the stage of the disease and correlate with the proportion of prolymphocytes. On the other hand, the proportion of Ki-67+ T cells (CD3+) was significantly higher in patients with CLL stage A' (29.3 +/- 4.5), which includes patients with long-standing, stable disease, than in CLL stage A" (9.5 +/- 3.3), B + C (7.1 +/- 4.6), and CLL/PL (6.4 +/- 2.8). Ki-67 seems to identify patients with more aggressive forms of CLL, such as CLL/mu 2PL with more than 10% Ki-67+ cells (25% of the cases) and Richter's syndrome, in which all the large lymphoma cells are Ki-67+. Long-term follow-up will establish whether Ki-67 is a good prognostic marker and can predict disease outcome.

Aged↗

The classification of acute leukaemia.

The standard methods for classifying acute leukaemias now include morphology, cytochemistry and membrane markers. Major advances in immunology, in particular the development of monoclonal antibodies (McAb) with lineage specificity, have provided objective positive criteria for the diagnosis of acute lymphoblastic leukaemia (ALL). The FAB group has recognised the importance of McAb for the classification of some forms of acute myeloid leukaemia (AML), such as megakaryoblastic leukaemia, AML-M7, in which reactivity with McAb against platelet glycoproteins is a requirement for diagnosis. More recently the group has defined a type of myeloblastic leukaemia with minimal differentiation, AML-MO, in which myeloid cytochemistry is negative and the diagnosis is made by the expression of myeloid antigens and negative lymphoid markers in the blast cells. However, new problems have emerged with the wider use of McAb which now need to be addressed: the most important is the precise evaluation criteria for biphenotypic leukaemia for which we have proposed a scoring system in order to recognise the genuine cases which constitute a distinct disease entity. The role of karyotyping in the classification of acute leukaemia is gradually being defined (MIC proposals) and some forms of acute leukaemia can only be diagnosed by chromosome translocations, e.g. Ph+ ALL, resulting from t(9;22) and t(4;11) in infant ALL. Several translocations can also be demonstrated by molecular techniques. Cases with t(8;16) (p11;p13) are characterised by myelomonocytic features, erythrophagocytosis and fibrinolysis and represent a type of AML which can be defined primarily by its cytogenetic abnormality.

Acute Disease↗

Low frequency of ras oncogene mutations in Philadelphia-positive acute leukemia and report of a novel mutation H61 Leu in a single case.

Activating ras mutations are frequent (25-60%) in chronic myelomonocytic leukemia (CMML) and in acute myeloid leukemia (AML) (30%), in contrast to chronic myeloid leukemia (CML) in which the incidence is very low (0-3%). This might reflect that the leukemic cell in CML is at a level of differentiation in which ras gene activation is not involved or, alternatively, might be due to the presence in CML of the bcrlabl fused gene. We have analyzed the presence of point mutations in codons 12, 13, 59, 61 and 63 of N-, K-, and H-ras genes, in 26 cases of Philadelphia-chromosome-positive, bcrlabl-positive acute leukemia (Ph+ AL), and in eight CMML cases by using the polymerase chain reaction. Aberrant ras genes were detected in a single Ph+ AL case, and in four out of eight CMML patients. The Ph+ AL showing altered ras allele had an unusual point mutation in H-ras gene, substituting leucine for glutamine. This mutation has not been previously found in any hematological disease. Our findings suggest that ras mutations are probably not involved in the pathogenesis of those leukemias in which blast cells contain bcrlabl oncogene activation.

Codon↗

Clinical and laboratory features of 78 cases of T-prolymphocytic leukemia.

We describe the clinical and laboratory findings of 78 adult patients with T-prolymphocytic leukemia (T-PLL) studied over the last 12 years. The main disease features were splenomegaly (73%), lymphadenopathy (53%), hepatomegaly (40%), skin lesions (27%), and a high leukocyte count (greater than 100 x 10(9)/L in 75%) with nucleolated prolymphocytes. A variant form with small, less typical cells was recognized in 19%. Membrane markers defined a postthymic phenotype TdT-, CD2+, CD3+, CD5+, CD7+; in 65%, the cells were CD4+ CD8-, in 21%, they coexpressed CD4 and CD8, and, in 13%, they were CD4- CD8+. Serology for human T-cell leukemia/lymphoma virus Type-I (HTLV-I) was negative in the 27 cases investigated. Cytogenetic analysis in 30 cases showed a consistent abnormality of chromosome 14, usually inv (14), with breakpoints at q11 and q32 in 76% of cases. Trisomy 8, including iso8q, was shown in 53%; t (11;14)(q13;q32) was documented in one case; and one had a normal karyotype. The clinical course was progressive with a median survival of 7.5 months. Thirty-one patients were treated with 2' deoxycoformycin and 15 responded (3 complete remissions and 12 partial remissions); the response rate (48%) increased to 58% in patients with a CD4+ CD8- phenotype. The median survival of responders was 16 months and of nonresponders 10 months; other treatments were less effective. T-PLL is a distinct clinico-pathologic entity with aggressive course and characteristic chromosome abnormalities. A subgroup of patients may benefit from deoxycoformycin.

Adult↗

A classification of acute leukaemia for the 1990s.

The need for reproducibility in the classification of acute leukaemia has made it necessary to incorporate information derived from new techniques which have become essential for the study of these disorders. In addition to classic morphology and cytochemistry (FAB proposals), it is necessary to add immunology and cytogenetics (MIC proposals), as well as to investigate further the biological and diagnostic significance of molecular events. As a result of these investigations a new group of leukaemias merit recognition as distinct entities. These include three types of ALL with specific chromosome abnormalities, namely, i) t (9;22), ii) t (4;11) and iii) t (1;19) and four subtypes of AML, i) with minimal differentiation or AML-M0, ii) with basophilic precursors or M2Baso, iii) AML (M4/M5) with t (8;16) and iv) AML with trilineage myelodysplasia. Biphenotypic acute leukaemia constitutes also a distinct entity with features of ALL and AML and represents a malignancy probably affecting multipotent stem cells. We propose an objective evaluation system for biphenotypic leukaemias based on a score in which the various lineage markers are graded according to their known specificity.

Humans↗

HTLV-1 envelope sequences from Brazil, the Caribbean, and Romania: clustering of sequences according to geographic origin and variability in an antibody epitope.

We sequenced the envelope genes of Human T-cell leukemia type I viruses (HTLV-I) derived from five Brazilian, two Caribbean, and one Romanian case of adult T-cell leukemia after amplification of the complete env gene by PCR. A comparison with previously reported HTLV-I sequences revealed that, although highly homologous, no two env sequences were identical. All envelope sequences differed from each other by 0.3-2.1% nucleotide differences. The five Brazilian sequences clustered together and were about as different from each other (0.5-0.75% nucleotide difference) as were three previously reported Japanese sequences (0.7-0.95%). In contrast, sequences of Caribbean origin were less homogeneous (0.5-1.9% nucleotide differences within this group). The Romanian sequence was not significantly more divergent than any of the others and was closest to our two Caribbean sequences. We observed two changes in a region (aa 176-209) which has previously been shown to contain a linear antibody epitope recognized by most human sera from seropositive individuals. One of these changes affects the binding of monoclonal antibodies to this epitope demonstrating the variability of an antibody epitope in the HTLV-I envelope.

Amino Acid Sequence↗

Deoxycoformycin in the treatment of mature T-cell leukaemias.

We describe the results of treatment with 2'-deoxycoformycin (DCF) in 68 patients with post-thymic (mature) T-cell malignancies. These included: prolymphocytic leukaemia (T-PLL), 31, HTLV-1 + adult T-cell leukaemia/lymphoma (ATLL), 20, cutaneous T-cell lymphoma (CTCL), comprising mycosis fungoides and Sezary syndrome, 13, and large granular lymphocytic leukaemia, four. Two-thirds of patients were refractory to previous therapy, which included four drug combinations. DCF was given intravenously at 4 mg m-2 weekly for the first 4 weeks and then every 2 weeks until maximal response. Toxicity was very low with only one death resulting from prolonged neutropenia. Overall response rates, partial (PR) and complete. (CR), were 38%, with variations according to diagnosis. Best responses, 54%, were seen in CTCL but limited to Sezary patients, one CR, six PR, whilst none of the mycosis fungoides responded. Responses in T-PLL were recorded in 48% including three CR (of 8-12 months' duration unmaintained) and 12 PR. Fifteen per cent of responses were seen in ATLL. The only ATLL responders - two CR, one PR - were those patients who received combination chemotherapy prior to DCF, with reduction of tumour bulk but short of PR. When results were analysed according to membrane phenotypes it was apparent that responses were seen mainly in cases with CD4+, CD8- T cells -22 of 47 (47%) - contrasting with only three of 19 (16%) with other T-cell phenotypes. We conclude that DCF is a useful therapy for the treatment of T-cell leukaemias, in particular Sezary syndrome and T-PLL, and should play a part in strategies to improve the natural history of this group of lymphoid malignancies.

Adult↗

Splenic lymphoma with villous lymphocytes: natural history and response to therapy in 50 cases.

We studied the natural history and response to treatment in 50 patients with splenic lymphoma with villous lymphocytes followed for a minimum of 6 months and up to 15 years (median 3.7 years). The disease occurs in the elderly (median 68 years) and affects males more than females (M/F ratio 1.77). The median survival for the group was not reached but 82% were surviving at 3 years and 78% at 5 years. Twelve patients (24%) died, one-third of deaths were disease related (four patients) and one-half were due to cardiovascular disease or another malignancy (six patients). The outcome was worse for males (31% died) than females (11% died). Fourteen patients were not treated and 10 remain alive between 1 and 6 years from diagnosis. The remaining patients were treated by chemotherapy, splenic irradiation or splenectomy. The response to chemotherapy was poor and only eight of 22 (36%) patients treated achieved a good response. Splenic irradiation was employed in seven patients and three benefited from it. Splenectomy seems to be the treatment of choice, with significant improvement seen in 19 of 20 patients with one post-operative death. This response, lasting from 6 months to 7 years (median 4 years), was seen irrespective of whether splenectomy was the initial treatment or used later in management.

Adult↗