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L Florensa

Publications and source records attributed to L Florensa.

At least 37 records · Page 2Linked to original sources

Application of cross-species color banding (RxFISH) in the study of T-prolymphocytic leukemia.

BACKGROUND AND OBJECTIVE: Cross-species color banding (RxFISH) is a new FISH technology based on the use of differentially labeled gibbon chromosome probes to obtain a specific color banding pattern for each human chromosome. The aim of the study was to test the RxFISH technique for better characterization of complex karyotypes in patients with T-prolymphocytic leukemia (T-PLL). DESIGN AND METHODS: The study evaluated the cross-species color banding technique in four patients affected with T-PLL previously studied by conventional cytogenetics. RESULTS: All patients showed an abnormal karyotype and three of them had a complex karyotype. The involvement of 14q11 in all four cases, the gain of 8q in three cases and a loss of chromosome 10, 15 and 17 and a gain of chromosome 21 in two cases were noted. The RxFISH technique identified from 2 to 7 not previously recognized aberrations per case and confirmed the inv(14)(q11q32). INTERPRETATION AND CONCLUSIONS: To our knowledge, this is the first application of RxFISH to characterize chromosomal rearrangements in T-cell neoplasms. RxFISH gave rapid and easy identification of chromosome rearrangements that were difficult to recognize by conventional cytogenetics. Using this new technology we identified 15 rearrangements not detected by conventional cytogenetics.

Adult↗

Cytogenetic findings in five patients with hairy cell leukemia.

We studied five cases of hairy cell leukemia (HCL) using conventional cytogenetics. All patients were diagnosed with typical HCL. Chromosome analysis was carried out on a 72-hour culture of peripheral blood. Phytohemagglutinin (PHA) mitogen was used. Clonal chromosome abnormalities were found in 2/5 patients (40%), a complex abnormality being identified in one of them. The chromosomes involved were: 1, 6, 7, 8, and 17. No patient showed trisomy 12 or a 14q+. An interesting result was the finding of del(7)(q32) as a sole anomaly.

Aged↗

Translocation (11;14)(q13;q32) and preferential involvement of chromosomes 1, 2, 9, 13, and 17 in mantle cell lymphoma.

We have studied 13 cases of histologically confirmed mantle cell lymphomas (MCL) combining cytological-immunological features with conventional cytogenetics and in situ hybridization (ISH) techniques. Peripheral blood smears and lymph node biopsies expressed the typical mantle zone pattern with alpha B-cell phenotype. Most of the cases (11 of 13) had lymphomatous cells in the peripheral blood. Chromosome analysis was carried out on lymphoid cells from peripheral blood and/or lymph node biopsies. Phytohemagglutinin (PHA) and phorbol 12-myristate 13 acetate (TPA) were used as mitogens. Biotin-labeled libraries of whole chromosomes implicated in complex karyotypes were used to improve their interpretation. Clonal chromosome abnormalities were found in 10 of 13 patients (77%); 7 of these had a complex abnormality. The most frequent recurrent structural abnormalities were: t(11;14)(q13;q32), involvement of chromosome 1 (der[1], del[1], dup[1]), chromosome 2 (del[2], der[2]), chromosome 9 (der[9], -9), chromosome 13 (add[13], t[13q]), and chromosome 17 (add[17], der[17], t[17q]). The most frequent numerical abnormalities were monosomy 21 and loss of the Y chromosome.

Adult↗

Major vascular complications in essential thrombocythemia: a study of the predictive factors in a series of 148 patients.

To determine the clinicohematological factors predictive for the appearance of major vascular complications (MVC) in patients with essential thrombocythemia (ET), 148 consecutive such patients were retrospectively assessed for the development of MVC during a median follow-up of 58.5 months. Seventy-seven patients had vascular risk factors, and 37 a history of MVC at ET diagnosis. Forty-nine MVC were registered in 33 patients during the follow-up period. The actuarial probability of MVC was 27% at 6 years in the whole series, 35.6% for patients above 60 years, and 21.4% for patients younger than 60 years, whereas only one of the 36 patients younger than 45 years had MVC. At multivariate analysis, age >60 years, history of major ischemia and hypercholesterolemia were the variables associated with an increased MVC risk. These results suggest that all ET patients above 60 years should be treated, whereas in younger patients treatment decisions should be primarily based on the existence of risk factors for MVC.

Adolescent↗

Two new cases of near-tetraploidy in adult acute myeloid leukemia.

Tetraploid or near-tetraploid karyotype has been described rarely in hematologic neoplasms. Herein we report two new cases of adult acute myeloblastic leukemia, M0 and M1 FAB subtypes that showed near-tetraploid clones that were studied with conventional cytogenetics and in situ hybridization (ISH). We compare our new cases with those previously reported.

Aged↗

[Cytogenetic study of 93 myelodysplastic syndromes].

BACKGROUND: We describe the cytogenetic results of 93 patients with myelodysplastic syndromes (MDS). The main object of this report is to analyze the prognostic value of the karyotype in patients with MDS, in relation to the evolution to acute leukemia and the survival time. PATIENTS AND METHODS: Cytogenetic studies were performed in 93 untreated cases of MDS between 1985 and 1994. Overall survival and the evolution to acute leukemia were analyzed. RESULTS: Among 93 patients who were examined at the time of diagnosis, 40 had an abnormal karyotype (43%). The highest frequency of chromosome abnormalities was observed in refractory anaemia with excess of blasts (RAEB) (65.7%) and RAEB in transformation (RAEB-t) (40%) and the lowest in refractory anaemia with ringed sideroblasts (RARS) (10%). The chromosomes most frequently involved were: 5, 7, 8, 11, 12 and 17. No relationship was found between FAB subtypes and the type of chromosomal abnormalities. In respect to the prognosis, an abnormal karyotype, and a complex karyotype were related with a higher frequency of evolution to acute leukemia. A model based on karyotype could divide patients in two groups: poor prognosis (patients with an abnormal karyotype, with involvement of chromosome 7, trisomy 8 or with a complex karyotype), and a good prognosis (patients with normal karyotype). CONCLUSIONS: The cytogenetic studies are very useful in the study of MDS for their clinical implications.

Adolescent↗

Cytogenetic abnormalities in three patients with B-cell prolymphocytic leukemia.

We present the cytological features, conventional cytogenetics, and in situ hybridization (ISH) findings of three cases of B-cell prolymphocytic leukemia (B-PLL). The diagnosis was made according to the French-American-British (FAB) criteria. We considered a diagnosis of B-PLL when a predominance (> 50%) of lymphoid cells with coarse chromatin but prominent central nucleoli and more abundant cytoplasm than typical chronic lymphocytic leukemia (CLL) cells were present. B-PLL express strong SIg, B-cell antigens, and reactivity with the monoclonal antibody FMC7. Chromosome analysis was carried out on lymphoid cells from peripheral blood and, in one patient, from lymph node. The phytohemagglutinin (PHA) mitogen was used. ISH was performed with two types of probes: the biotin-labeled chromosome 12-specific alpha satellite DNA probe to detect trisomy 12, and biotin-labeled libraries of whole chromosomes 1, 7, and 14. Clonal chromosome abnormalities were found in all three patients; in one, a complex karyotype was observed. The most frequent recurrent abnormality was trisomy 12. Our results suggest that PLL usually presents with cytogenetic abnormalities. The finding of translocation (11;14) is noteworthy; chromosomes 1 and 3 are also involved.

Adult↗

[Interstitial 9q deletion: a primary change in acute non-lymphoblastic leukemia?].

Two cases of acute non-lymphoblastic leukaemia (ANLL), subtypes M1 and M5b, are presented. Both of them showed the 9q-interstitial deletion as the only abnormality. From our observations and others found in the literature it can be inferred that such abnormality might be a primary finding in ANLL, related to an unfavourable prognosis, regardless the morphological subtype.

Aged↗

[Contribution of phenotyping cells in metaphase and interphase (MAC and MACISH techniques) to the study of hematologic neoplasms].

BACKGROUND: Banding techniques are essential in the chromosomal analysis for the cytogenetic diagnosis. Even that, conventional cytogenetic techniques destroy the cytoplasmic membrane and the lineage involvement of the karyotyped cells is unknown. In this work the usefulness of a method that keeps the cell intact and allows the sequential application of immunological, cytochemical, morphological and cytogenetic techniques in the same cell is shown. This technique is called MAC for morphology, antibodies and chromosomes. The combination of MAC and in situ hybridization techniques (MACISH method) allows the detection of a chromosome abnormality in all the cells even when no mitosis are present. PATIENTS AND METHODS: The MAC method was applied in 51 patients and the MACISH method in 9 patients in order to identify the cells which karyotype is analyzed. We have studied 47 patients with normal karyotype (37 chronic lymphocytic leukaemia [CLL] and 10 essential trombocythaemias (ET) and 4 patients with different diseases and abnormal karyotype. RESULTS: Among 37 patients with CLL and normal karyotype, in 9 cases only normal T-cells were in mitoses and in 28 cases the normal karyotype belonged to neoplastic B cells. Trisomy 12 has been confined exclusively to the leukaemic B cells with the MACISH technique in 3 of these CLL cases. In 10 patients with ET and normal karyotype the MAC method showed that in any case the mitosis analyzed belonged to the megakaryocyte lineage. In 4 patients with different chromosomal abnormalities the haematological cell lines involved in the neoplasia were known with the MAC method. CONCLUSION: In this work is shown the usefulness of the combination of the MAC and MACISH techniques with conventional cytogenetics in order to complete the chromosomic study of the haematological neoplasms is confirmed. These methods are specially usefull when different cell lineages are involved in the neoplasia, reactive proliferations are suspected, or to discard false aneuploidies.

Hematologic Neoplasms↗

Lymphocytes with cerebriform nuclei in chronic B-cell lymphoproliferative diseases.

Two patients with chronic lymphoproliferative diseases, a splenic marginal zone lymphoma and hairy cell leukaemia variant, were reported. In both diseases a B-immunophenotype was demonstrated but a variable percentage of lymphoid cells (30 and 52%) showed a highly irregular nuclear outline, sometimes mimicking the nuclei of Sézary cells.

Aged↗