Cytogenetic test and clinical study on cryptic acute promyelocytic leukemia with ins (15; 17) / 中华血液学杂志

Objective: To investigate the genetic screening methods for cryptic acute promyelocytic leukemia (APL) to further explore its clinical prognosis. Methods: From June 2016 to November 2018, we collected 373 newly diagnosed APL cases. The patients were retrospected by the results of PML-RARα detections both by RT-PCR and i-FISH, those who harbored positive PML-RARα detection by RT-PCR and negative by i-FISH were chosen. Metaphase FISH and Sanger sequencing were further performed to verify these results. Results: A total of 7 cryptic APL cases were discovered. These cases had tiny fragment of RARα inserted into PML in chromosome 15, formed ins (15;17) . The 7 cryptic APL cases had no PML-RARα gene subtype specificity, involving 5 cases in L subtype, 1 case in S subtype and 1 case in V subtype respectively. After the treatment of retinoic acid and arsenic or anthracyclines, 6 cases achieved complete remission, 1 case died of intracranial hemorrhage on the 6th day of therapy. Conclusion: The size and covering position of PML-RARα probe should be taken into account when PML-RARα was performed by FISH on APL patients. Furthermore, combination with Metaphase FISH could improve the recognition of cryptic APL. There were no differences between the cryptic and common APL patients in terms of clinical features and treatment choices. Cryptic APL patients also had a good response to the therapy of retinoic acid and arsenic or anthracyclines.

Clinical and Cytogenetic Characteristics of Two AML Patients with High-level MLL Expression / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the clinical and cytogenetic characteristics of high-level mixed-lineage leukaemia (MLL) gene amplification in patients with acute myeloid leukemia (AML).</p><p><b>METHODS</b>The clinical and cytogenetic data of 2 AML patients with high-level MLL amplification from January 2010 to August 2016 were analyzed retrospectively.</p><p><b>RESULTS</b>The two AML cases were in middle-aged population. They were diagnosed as FAB subtype M5b and M2a respectively. Both of them had complex karyotypes with the aberrations of chromosome 11. One case was confirmed as MLL-PTD involving exons 2-9 by RT-PCR and sequencing. The other case without MLL-PTD was further analyzed by CytoScan HD analysis. The CMA results showed partial gain of 11q accompanied with partial loss in 11q, deletion of regions in 3p, 3q, 4q, 5q, 7q, 8q, 10p, 10q, 12p and 18q, as well as gain of 4p.</p><p><b>CONCLUSION</b>The co-existence of -5/5q-, -7/7q- and highly complex karyotype may accelerate the poor prognosis. Thus how those cytogenetic abnormalities influencing the disease prognosis need to be further explored.</p>

Application of Combined Detection of Fusion Gene and BIOMED-2 Standardized Ig Gene Rearrangement System in Childhood B-cell Acute Lymphoblastic Leukemia / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the application of combined detection of fusion gene and BIOMED-2 standardized immunoglobulin (Ig) gene rearrangement system in diagnosis and treatment of children with acute lymphoblastic leukemia (ALL).</p><p><b>METHODS</b>Multiplex-PCR amplifications and RQ-PCR of RNA/DNA were performed using ALL fusion gene detection kit and BIOMED-2 primer. The Ig gene rearrangements were analyzed by using PCR fragment analysis system.</p><p><b>RESULTS</b>Out of 251 children with B-ALL, 77 cases were TEL-AML1(+) , 28 cases were E2A-PBX1(+) , 10 cases were MLL-AF4(+) , 11 cases were BCR-ABL(+) , the total positive rate was 50.2%, 82.5% showed IgH VH-JH rearrangement, 53.4% showed IgK rearrangement. The positive rate of combined detection of fusion gene and gene rearrangement was 99%. E2A-PBX1(+) and MLL-AF4(+) with IgK(+) gene rearrangement group was compared with negative control group, the difference was statistically significant (P < 0.001 or P = 0.005); 105 ALL fusion gene positive cases had been detected by fluorescence in situ hybridization (FISH) simultaneously, the accordance rate of fusion gene and FISH was more than 94%.</p><p><b>CONCLUSION</b>The combined detection of ALL fusion gene and BIOMED-2 standardized clonality analysis system can improve the positive detected rate of B-ALL dramatically, and make the grouping of disease prognosis more accurately; this combined detection is a more faster and sensitive method than FISH.</p>

Immunophenotypes, cytogenetics and clinical features of 192 patients with acute myeloid leukemia / 中国实验血液学杂志

The objective of this study was to investigate the immunophenotypic subtype profiles of 192 patients with acute myeloid leukemia (AML) and its association to cytogenetics and clinical features. Immunophenotyping of 192 patients was performed by flow cytometry using a panel of monoclonal antibodies. The karyotypes in 125 out of 192 cases were analyzed by G-banding technology. The results showed that CD33, CD13, myeloperoxidase (MPO) and CD117 were the most commonly expressed antigens in AML. CD117 expressed in 84.6% of AML-M3 cases. A combination of intensive autofluorescence, both CD34- and HLA-DR-, and high expression of CD13, CD33 and MPO had significant value for AML-M3 diagnosis. CD14 expressed only in AML-M4 and AML-M5, and both intensive positivity of CD64 and CD15 with high expression of HLA-DR may suggest great possibility for diagnosis of AML-M5. Lymphoid marker expression was documented in 47.9% of the 192 AML cases. CD56 (26.0%) and CD7 (20.8%) were the most commonly expressed lymphoid markers in AML patients, followed by CD19 (9.9%) and CD2 (7.3%). Abnormal karyotypes were detected in 76 out of 125 cases (60.8%). Correlation test showed that t(8;21) was found only in 17 cases of AML-M2 and strongly associated with the individual or combinational expressions of CD15/CD19/CD56. And 28 cases of t(15;17) were found in AML-M3; 2 cases of inv(16) were found in AML-M4EO. Higher CD34 positivity was found in LymAg+ group (77.2%) than that in LymAg- group (48.0%). It is concluded that immunophenotype analysis is useful for AML diagnosis and classification, and the immunophenotype has close relevance to the abnormal cytogenetic changes and clinical features in AML. The results suggested that a new prognostic scoring system that integrated the morphology, cytogenetic abnormalities and immunophenotype parameters would benefit the diagnosis, classification, and estimation of prognosis in AML patients.

Laboratory study on near-tetraploid acute myelogenous leukemia of childhood / 中国当代儿科杂志

Near-tetraploidy is a rare cytogenetic abnormality in myelocytic malignancies in children, and its significance is unknown. To investigate the characteristics of near-tetraploidy in a child with acute myelogenous leukemia (AML-M4), bone marrow smears were prepared for morphological analysis. Bone marrow samples were collected for flow cytometry, and prepared by short-term (24 hrs) unstimulated culture and R-banding for conventional cytogenetic assay. In this case, the morphological analysis of bone marrow cells showed large and prominent nuclei. The chromosomal analysis (R-banding) demonstrated a near-tetraploidy. Combined with morphological and immunophenotypic results, AML-M4 was confirmed. The patient was given four cycles of chemotherapy, and finally achieved clinical remission. However, the duration achieving the remission in the child was longer than AML children with normal karyotype. It is believed that near-tetraploid karyotype may have a great significance to the therapy and prognosis.