RESUMO
We report the case of a 62-year-old man who presented with splenomegaly, leukocytosis, anemia, and thrombocytopenia. Examination of the peripheral blood, bone marrow, and spleen revealed involvement by mantle cell lymphoma, with some blastoid features and an atypical phenotype. Spleen and bone marrow classical chromosome analysis followed by fluorescence in situ hybridization revealed a novel and unusual unbalanced variant of the t(11;14)(q13;q32) translocation, resulting in a complex derivative chromosome harboring the IGH/CCND1 fusion gene. This chromosome was designated as der(14)t(11;14)(q13;q32)t(11;14)(p11.1;p11.2).
Assuntos
Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 14/genética , Variação Genética , Linfoma de Célula do Manto/genética , Translocação Genética , Desequilíbrio Alélico , Neoplasias da Medula Óssea/genética , Ciclina D1/genética , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Neoplasias Esplênicas/genéticaRESUMO
A 3-year-old patient presented with anemia, thrombocytopenia, and blasts in the peripheral blood. A bone marrow aspirate revealed a myelodysplastic syndrome (MDS). A mosaic abnormal female karyotype 46,XX, t(1;19)(q42; p13.1)c[12]/ 47,idem,+21c[3]/ 47,idem,-7,+21c,+mar[7] was obtained on G-banded metaphases from unstimulated bone marrow aspirate cell culture. To rule out constitutional abnormalities, we performed a cytogenetic analysis on the patient's phytohemagglutinin-stimulated peripheral blood and cultured skin fibroblasts. A karyotype of 46,XX,t(1;19) (q42;p13.1)c was found in all 20 peripheral lymphocytes analyzed, confirming the constitutional origin of the translocation. In addition, 5 out of 50 cells from two separate cultures of the skin fibroblasts contained an extra chromosome 21. The presence of two cell lines in multiple cultures indicates that the patient is a true low-level mosaic for trisomy 21. Because of the finding of monosomy 7 and a marker chromosome only in the trisomy 21 clone, we conclude that the leukemic clone arose from a hematopoietic precursor with constitutional trisomy 21. It is also possible that the t(1;19) played some role in the development of the MDS. Because acute myelogenous leukemia (AML) and MDS with Down syndrome (DS) have distinct biologic and clinical features, the identification of DS patients with a mild or normal phenotype in the AML/MDS population is of fundamental importance for clinical diagnosis and management.
Assuntos
Síndrome de Down/complicações , Monossomia , Mosaicismo , Síndromes Mielodisplásicas/genética , Translocação Genética , Pré-Escolar , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 19 , Cromossomos Humanos Par 7 , Feminino , Humanos , Cariotipagem , Síndromes Mielodisplásicas/complicaçõesRESUMO
Two translocations involving the MALT1 gene have been described in extranodal marginal zone B-cell lymphomas of MALT type. A t(11;18)(q21;q21) involving API2 and MALT1 occurs in a subset of MALT lymphomas but with only rare exception is absent in diffuse large B-cell lymphomas (DLBCL), even at MALT sites. More recently, a t(14;18)(q32;q21) involving IGH and MALT1 has been described in nongastric extranodal MALT lymphomas. This translocation is indistinguishable from the IGH-BCL2 translocation by using classical cytogenetics. We report the IGH-MALT1 translocation in a cutaneous DLBCL as shown by classical cytogenetics and molecular cytogenetic analysis. This is the first report of an IGH-MALT1 translocation in DLBCL. These findings indicate that MALT1 translocations are not restricted to indolent-appearing lymphomas, provide further evidence that API2-MALT1 and IGH-MALT1 translocations exhibit biologic differences, have implications regarding the pathogenesis of some extranodal DLBCL, and emphasize that a t(14;18)(q32;q21) cannot be assumed to reflect a BCL2 translocation.
Assuntos
Genes de Imunoglobulinas , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , Proteínas de Neoplasias/genética , Neoplasias Cutâneas/genética , Idoso , Caspases , Aberrações Cromossômicas , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Feminino , Antebraço/patologia , Humanos , Hibridização in Situ Fluorescente , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Translocação GenéticaRESUMO
Classical cytogenetic studies have a critical role in the diagnosis of acute leukemias; however, they are much less widely used in lymphoma diagnosis. To evaluate their utility in this latter setting, G-banded karyotyping was performed on 279 consecutive lymph node or tissue biopsy specimens with suspected lymphoma. Complete cytogenetic studies were successfully obtained in 177 cases (63.4%), including 115 (69.3%) of 166 hematolymphoid neoplasms. Success rates varied with the specific diagnosis (range, 33%-100%). The karyotypes were abnormal in 97 (84.3%) of the hematolymphoid neoplasms. In at least 3 cases of non-Hodgkin lymphoma, the findings contributed directly to the specific diagnosis made. In a much larger proportion of cases, characteristic but nonspecific findings were identified. Abnormalities of suggested prognostic importance in follicular lymphoma and in diffuse large B-cell lymphoma were identified in 14 (44%) of 32 cases and 8 (24%) of 33 cases, respectively. Most karyotyped lymphomas will display abnormal findings including many that are not completely specific but support the diagnosis, some that provide additional prognostic information, and, infrequently, some that help establish a diagnosis that might otherwise have been missed.
Assuntos
Biomarcadores Tumorais/análise , Aberrações Cromossômicas , Linfoma/diagnóstico , Linfoma/genética , Citogenética , Humanos , Cariotipagem , Prognóstico , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
Cytogenetic studies provide important information for the diagnosis and classification of malignant lymphomas that in some cases also has prognostic significance. Furthermore, the investigation of isolated novel cytogenetic findings in malignant lymphoma has led to the discovery of many important oncogenes and tumor suppressor genes. For this reason, a case of nodal marginal zone B-cell lymphoma in a 72-year-old woman is described in which analysis by conventional and molecular cytogenetic techniques demonstrated the presence of a t(X:5)(q28;q22) as the sole chromosomal abnormality. This translocation has not been previously reported in the literature.
Assuntos
Cromossomos Humanos Par 5/genética , Cromossomos Humanos X/genética , Linfoma de Células B/genética , Translocação Genética/genética , Idoso , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Linfoma de Células B/patologiaRESUMO
We present the case of a 15-year-old female with acute promyelocytic leukemia and a new variant chromosome rearrangement identified as ins(15;17)(q22;q12q21) by conventional cytogenetic analysis. This finding was confirmed by fluorescence in situ hybridization using the PML-RARA DNA probe and whole chromosome paints 15 and 17. A typical PML-RARA fusion transcript consistent with a breakpoint in intron 3 of the PML gene and intron 2 of the RARA gene was identified by reverse transcription polymerase chain reaction.