Two cases of acute myeloid leukemia with t(11;17) associated with varying morphology and immunophenotype: rearrangement of the MLL gene and a region proximal to the RAR alpha gene
ABSTRACT This report describes 2 cases of acute myeloid leukemia (AML), which based on the WHO classification would be classified as AML with an 11q23 (MLL) abnormality, but with contrasting morphologic and immunophenotypic profiles. One case had monocytic features (morphologically and immunophenotypically) with a t(11;17)(q23;q21), a previously identified variant translocation in acute promyelocytic leukemia (APL). The second case had morphologic and immunophenotypic features of APL associated with a t(11;17)(q23;q25). In both cases, fluorescence-in-situ hybridization (FISH) analysis demonstrated that the 11q23 breakpoint involved the MLL gene, but RARalpha was not involved in the 17q breakpoints. These cases illustrate the importance of FISH analysis to confirm the presence of a particular recurring rearrangement.
Full-textDOI: · Available from: Cherie Dunphy, Jan 04, 2014
SourceAvailable from: Rolf MarschalekThe Korean journal of hematology 12/2012; 47(4):307-8. DOI:10.5045/kjh.2012.47.4.307
[Show abstract] [Hide abstract]
ABSTRACT: Clonal chromosome abnormalities are hallmarks of various cancer types. Non-random chromosome translocations have been identified in hematological malignancies over five decades due to their ability to yield informative metaphases. Among the various chromosome aberrations commonly found in different cancer types including deletions, duplications, and aneuploidy, balanced reciprocal translocations have been identified with remarkable specificity in hematological malignancies and soft tissue sarcomas. Recurrent chromosome aberrations are used as markers for diagnosis, prognosis, and treatment follow-up. The fusion and deregulated genes cloned from the site of translocation breakpoints are implicated in tumorigenesis. It has been well established that common molecular consequences of non-random reciprocal translocations result in the formation of a fusion gene from the breakpoints in the introns of two different genes on the same or different chromosome. Most of the fusion genes described in hematological malignancies are transcription factor genes and tyrosine kinases, conferring proliferative advantage to the leukemic clone.Cancer treatment and research 01/2009; 145:41-58. DOI:10.1007/978-0-387-69259-3_3
[Show abstract] [Hide abstract]
ABSTRACT: A 23-year-old male presented with pulmonary tuberculosis and swelling of both lower limbs. He was put on antitubercular treatment. Hemogram showed mild anemia and Pseudo Pelger-huet cells. The bone marrow (BM) examination showed 52% promyelocytes with regular round to oval nuclei, few granules and were positive for CD13 and CD33, and negative for HLA-DR. Cytogenetic analysis of the BM aspirate revealed an apparently balanced t(11;17)(q23;q21). Final diagnosis rendered was acute promyelocytic leukemia (APL) with t(11;17)(q23;q21); ZBTB16/RARA. APL is a distinct subtype of acute myeloid leukemia. The variant APL with t(11;17)(q23;q21) cases that are associated with the ZBTB16/RARA fusion gene have been reported as being resistant to all-trans-retinoic acid (ATRA). Therefore, differential diagnosis of variant APL with t(11;17)(q23;q12) from classical APL with t(15;17)(q22;q12); PML-RARA is very important. Here we have discussed the importance of distinct morphology of variant APL and also significance of rare presentation with tuberculosis.The Korean journal of hematology 09/2012; 47(3):229-32. DOI:10.5045/kjh.2012.47.3.229