Papers by María Eugenia Legues
Revista Medica De Chile, 2019
High risk cytogenetic abnormalities in patients with multiple myeloma Background: Cytogenetic abn... more High risk cytogenetic abnormalities in patients with multiple myeloma Background: Cytogenetic abnormalities observed in the bone marrow of patients with multiple myeloma (MM) are an important prognostic factor for risk stratification. Aim: To investigate karyotype characteristics and frequency of the high-risk cytogenetic abnormalities t(4;14), t(14;16) and del(17p) in Chilean patients with MM. Material and Methods: We studied 30 patients with MM by conventional cytogenetics (CC) and fluorescent in situ hybridization of plasma cells selected using cytoplasmic immunoglobulin staining (cIg-FISH). Results: Overall, the two techniques in combination allowed us to identify clonal genetic abnormalities in 47% of patients. The t(4;14) abnormality was observed in 19% of patients, del(17p) was observed in 10% of patients, and t(14;16) was not detected. Conclusions: Our results showed frequencies of high-risk abnormalities similar to those reported abroad. Cytogenetic studies should be performed routinely for all MM patients at the moment of diagnosis.
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Revista médica de Chile, 1994
Acute lymphoblastic leukemia (ALL) is the most frequent childhood cancer. The leukemic cells of A... more Acute lymphoblastic leukemia (ALL) is the most frequent childhood cancer. The leukemic cells of ALL patients show several well defined numeric and structural chromosomal abnormalities which are universally known for its prognostic implications. We studied a group of 44 children with ALL, to investigate the incidence of chromosome aberrations in ALL, its lymphocyte lineage and some clinical feature associations, and the finding of non previously described aberrations. A high proportion of patients (79.5%) showed chromosomal abnormalities. Most of them had a pseudodiploid karyotype (46 chromosomes), characterized mainly by a translocation. In relation to chromosome number, 27% of them were hyperdiploid with more than 50; 9% hyperdiploid between 47-50 and 7% hypodiploid (less than 46). Among structural aberrations found, were the following recurrent translocations: t (1; 19), t (4; 11), t (9; 22) in 6.8%, 9.1% and 2.3% of cases respectively, all related to an early B immunophenotype. O...
Journal of Pediatric Hematology/Oncology, 1996
Revista médica de Chile, 2019
Primary plasma cell leukemia. Report of five cases Background: Primary plasma cell leukemia (pPCL... more Primary plasma cell leukemia. Report of five cases Background: Primary plasma cell leukemia (pPCL) is uncommon, aggressive and has a different biology than multiple myeloma (MM). Aim: To report the features of patients with pPCL. Material and Methods: Review of databases of the Hematology Department and the Hematology laboratory. Results: Of 178 patients with monoclonal gammopathies, five (2.8%) patients aged 33 to 64 years (three females) had a pPCL. The mean hemoglobin was 7.3 g /dL, the mean white blood cell count was 52,500/mm 3 , with 58% plasma cells, and the mean platelet count was 83,600/mm 3. The mean bone marrow infiltration was 89%, LDH was 2,003 IU/L, serum calcium was 13 mg/dL, and creatinine 1.5 mg/dL. Two patients had bone lesions. Three were IgG, one IgA lambda and one lambda light chain. CD20 was positive in one, CD56 was negative in all and CD117 was negative in 3 cases. By conventional cytogenetic analysis, two had a complex karyotype. By Fluorescence in situ Hybridization, one was positive for TP53 and another for t (11; 14). One patient did not receive any treatment, three patients received VTD PACE and one CTD. None underwent transplant. Three patients are alive. The mean survival was 14 months. Conclusions: These patients with pPCL were younger and had a more aggressive clinical outcome than in multiple myeloma.
Revista médica de Chile, 2019
High risk cytogenetic abnormalities in patients with multiple myeloma Background: Cytogenetic abn... more High risk cytogenetic abnormalities in patients with multiple myeloma Background: Cytogenetic abnormalities observed in the bone marrow of patients with multiple myeloma (MM) are an important prognostic factor for risk stratification. Aim: To investigate karyotype characteristics and frequency of the high-risk cytogenetic abnormalities t(4;14), t(14;16) and del(17p) in Chilean patients with MM. Material and Methods: We studied 30 patients with MM by conventional cytogenetics (CC) and fluorescent in situ hybridization of plasma cells selected using cytoplasmic immunoglobulin staining (cIg-FISH). Results: Overall, the two techniques in combination allowed us to identify clonal genetic abnormalities in 47% of patients. The t(4;14) abnormality was observed in 19% of patients, del(17p) was observed in 10% of patients, and t(14;16) was not detected. Conclusions: Our results showed frequencies of high-risk abnormalities similar to those reported abroad. Cytogenetic studies should be performed routinely for all MM patients at the moment of diagnosis.
Revista médica de Chile, 1991
Cytogenetic studies were performed in 29 patients with myelodysplasia, 12 males and 17 females wi... more Cytogenetic studies were performed in 29 patients with myelodysplasia, 12 males and 17 females with a mean age of 61 years. The distribution of patients according to FAB groups were as follows: refractory anemia (RA) 7, sideroblastic refractory anemia SRA) 6, refractory anemia with excess blasts (RAEB) 12 and refractory anemia with transformation excess blasts (RAEB-t) 4. Cytogenetic anomalies were found in 48% over all, 78% in patients with RAEB and RAEB-t forms and only 23% in patients with simpler forms of myelodysplasia. Multiple and complex chromosomal alterations were found in 50% of abnormal studies, only in patients with complex forms. In general, structural rearrangements and deletions were less frequent than numeric defects, with a slight preponderance of chromosomal losses. Alterations of chromosomes 5, 7, 28, 21, 22, 8, 11 and 15 were the most commonly observed. Survival was decreased from 60 months in patients with normal karyotype to 6 months in those with chromosomal ...
British Journal of Haematology, 1996
We report the different presentation features and clinical outcome between two identical infant t... more We report the different presentation features and clinical outcome between two identical infant twins with acute lymphoblastic leukaemia with a shared clonal disease and MLL gene rearrangement. One twin relapsed and died, but the other is in complete remission >4 years after diagnosis. These data, and similar observations on other twin infants with leukaemia, suggest that despite a common clonal in utero, post-natally these leukaemias can evolve independently, at different rates, in the twinned individuals, and that the usually fatal leukaemia associated with t(4;11) MLL gene rearrangement can be effectively treated when the leukaemic burden is small.
Revista médica de Chile, 2002
Acute promyelocytic leukemia (APL) is characterized cytogenetically by t(15;17) (q22;q21) and its... more Acute promyelocytic leukemia (APL) is characterized cytogenetically by t(15;17) (q22;q21) and its molecular consequence, fusion of PML and RAR alpha genes. The detection of this genetic marker confirms the diagnosis and allows monitoring of the leukemic clone during treatment, which has prognostic value. Cytogenetics fails in some cases due to the absence of metaphases in cultures or their bad morphology. Southern blot and PCR methods require trained personnel and adequate equipment. FISH method allows the identification of chromosomic rearrangements in 24 to 48 h and is simple to set up in a cytogenetics laboratory. To evaluate the FISH method to detect PML/RAR alpha fusion, compared to cytogenetic analysis. Fifteen bone marrow specimens from APL patients with previous cytogenetic analysis were studied, using a commercial probe to detect PML/RAR alpha fusion. We obtained a normal cut-off value of 9.1%. Specificity and sensibility were 100%. Six positive cytogenetic cases at diagnos...
Revista médica de Chile, 2002
... 2. DOUER D, PRESTON-MARTIN S, CHANG E, NICHOLS P, WATKINS K, LEVINE A. High frequency of acut... more ... 2. DOUER D, PRESTON-MARTIN S, CHANG E, NICHOLS P, WATKINS K, LEVINE A. High frequency of acute promyelocytic leukemia among latinos with acute myeloid leukemia. ... Gabriela Repetto por la lectura crítica del manuscrito. Correspondencia a: María E Legües. ...
Cancer Genetics, 2011
Chronic myeloid leukemia (CML) is characterized by the presence of the Philadelphia chromosome (P... more Chronic myeloid leukemia (CML) is characterized by the presence of the Philadelphia chromosome (Ph), which results from a balanced translocation between chromosomes 9 and 22, the t(9;22)(q34;q11.2). In 5e10% of the cases, variants of the Ph (vPh) are detected, involving various breakpoints in addition to 9q34 and 22q11.2. Deletions on the der(9) and der(22) can be detected in approximately 10e15% of CML patients. The frequency of a deletion of the der(9) in vPh CML is variable. Most studies have shown high frequencies (30e45%) in this subgroup. We report the cytogenetic evaluation of 25 vPh cases, which represents 6.8% of the CML cases diagnosed at one institution in 20 years. The breakpoints of the partners of the vPh in our patients agree with those reported previously, except for a novel 18q23. We found a low incidence of deletions of the der(9) (10%) and der(22) (5%) in these patients, contrasting with several reports in the literature. This finding may reflect the extensive spectrum of aberrations in vPh, and the possibility that a considerable group of these aberrations may not affect the genetic stability of 5 0 ABL1 and 3 0 BCR. Epidemiologic differences may also exist and could explain our results. These differences would require further investigation.
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Papers by María Eugenia Legues