Philadelphia chromosome detection in chronic myeloid leukemia: Utility of phytohemagglutinin-stimulated peripheral blood culture.

Background: The conventional cytogenetic approach to demonstrate Philadelphia (Ph) chromosome at times does not yield enough number of metaphases or are of suboptimal quality. Further, the rapid molecular tests have completely pushed this simple technique into disrepute. Aims: This study aimed to evaluate usefulness of phytohemagglutinin (PHA)-stimulated peripheral blood culture for detection of Ph chromosome in chronic myeloid leukemia (CML) patients. Materials and Methods: Fifty-six patients, including 11 newly diagnosed cases of CML and 45 patients of CML on imatinib therapy showing the presence of Ph chromosome in unstimulated samples, were included in the study. Cytogenetic analysis was done on unstimulated samples, i.e. bone marrow aspirate, 24- and 48-h peripheral blood culture, and compared with PHA-stimulated 72-h peripheral blood culture. Results: The preparations from PHA-stimulated peripheral blood culture samples in all 56 patients yielded high number of good-quality metaphases. All the 11 (100%) newly diagnosed patients and 39/45 (87%) of the patients on imatinib therapy showed the presence of Ph chromosome in PHA-stimulated samples. Addition of PHA-stimulated 72-h peripheral blood culture preparation can be of use for increasing the diagnostic yield in cases of CML with suboptimal results on conventional cytogenetics from bone marrow aspirate sample.

Karyotypic study of chronic and blastic phase chronic myeloid leukemia patients of Gujarat State.

For present work, 27 clinically diagnosed Chronic Myeloid Leukemia patients were selected, who attended the Out Patient Department of Gujarat Cancer and Research Institute, Ahmedabad. In all these cases relevant history, clinical findings, haematological data and other investigations were noted & bone-marrow samples were obtained for further study, which was done at Genetics Laboratory, B.J. Medical College, Ahmedabad. Samples were cultured, harvested, slides were prepared & photographs were obtained using photomicroscope and Karyotypes were prepared by using conventional cut and paste technique. Cytogenetic evaluation was done to detect the presence of Philadelphia chromosome and/or other chromosomal abnormalities. Out of 27 patients studied, 22 cases were having mild to moderate & remaining 5 cases were having huge splenomegaly. The blood picture showed, 9 were anaemic; 11 having total leukocytic count more than 1 lakh/mm3 ; 8 cases were thrombocytopenic. 25 cases were in chronic and 2 cases were in blastic phase. Cytogenetic evaluation by Karyotypes revealed 13 Ph’ positive cases; 4 Ph’ negative; 3 mosaic & remaining 7 cases came out inconclusive. All relevant parameters including clinical, hematological and cytogenetic were evaluated, analyzed and compared with other similar studies.

Frequencies of BCR-ABL1 fusion transcripts among Sudanese chronic myeloid leukaemia patients

The incidence of one or other rearrangement in chronic myeloid leukemia (CML) patients varies in different reported series. In this study we report the frequencies of BCR-ABL1 fusion transcript variants studied in 43 CML patients from Sudan. The study includes 46 Sudanese patients, three of which negative for the BCR-ABL1 fusion transcript. More than half of 43 positive patients showed b2a2 fusion transcript (53.5 percent), while (41.9 percent) showed b3a2 transcript and the remaining (4.6 percent) coexpression of b3a2/ b2a2 and b3a2/b2a2/e19a2. We detected neither coexpression of p210/p190 nor e1a2 alone. Male patients showed a tendency to express b2a2, while female tende to express b3a2 (p = 0.017). Moreover, a single nucleotide polymorphism was detected in BCR exon 13 in one out of four patients and this patient showed only b2a2 expression. In conclusion, we observed a significant correlation between sex and type of BCR-ABL1 transcript, an observation that deserves further investigation.

An analysis of multiplex-PCR in the detection of BCR-ABL transcripts in hematological disorders

In this work, we describe the advantages of multiplex-PCR in the specific detection of BCR-ABL transcripts in different hematological disorders and its sensitivity compared to nested PCR. Fifty-three patients were studied for the presence of BCR-ABL transcripts: 24 patients with chronic myeloid leukemia (CML), 20 with acute leukemia (AL), and 9 patients with other hematological disorders. A variant rearrangement (b3a3) was found in a single case of CML (4.2 percent). Four out of the 20 patients with AL (20.0 percent) (14 adults, 6 children) were bcr-abl(+), and in this group three cases were classified as B-acute lymphoblastic leukemia (B-ALL), and one as acute myeloblastic leukemia (AML). Two of the three patients with B-ALL were positive for b2a2 and the other one for e1a2, while in the BCR-ABL(+)AML patients a b3a2 rearrangement was observed. In conclusion, multiplex-PCR allows rapid, specific and simultaneous detection of different types of BCR-ABL transcripts in CML and ABL-BCR(+)AL. A full correlation was observed when multiplex-PCR was compared with nested PCR.

Biphenotypic Acute Leukemia with BCR-ABL mRNA Transcript b3a2 Type: A Case Report with Review of the Literature / 대한진단검사의학회지

Biphenotypic acute leukemia (BAL) is a subtype of leukemia of ambiguous lineage in the World Health Organization classification system. About one third of the cases have the Philadelphia chromosome, and some cases are associated with other structural abnormalities involving 11q23. BAL is known to have a poor prognosis in both children and adults. According to the previously reported BAL cases with positive BCR-ABL fusion gene, most of the BCR-ABL mRNA transcript type was e1a2. So, we describe here a 30-year-old adult BAL case with the karyotype 46,XY,t(9;22)(q34;q11.2) resulting in a very rare b3a2 type of BCR-ABL mRNA transcript.

Two Cases of Philadelphia Chromosome-negative Essential Thrombocythemia Manifested bcr-abl Gene Rearrangement / 대한임상병리학회지

Discrepant results have been reported in terms of detecting bcr-abl transcripts in patients with essential thrombocythemia that are Philadelphia (Ph) chromosome-negative. We present two cases of Ph chromosome-negative essential thrombocythemia in whom bcr-abl gene rearrangement was detected. In the diagnosis of both cases, they lacked the splenomegaly, anemia and basophilia, and had high platelet counts (948X10(3)/L and 1,329X10(3)/microL, respectively) and normal leukocyte alkaline phosphatase (LAP) scores on admission without any evidence of inflammation, infection, or therapy. They lacked the Philadelphia chromosome characteristic of classical chronic myelogenous leukemia (CML) and had b3a2 transcripts.