Search

Simple Summary: Current recommendations suggest setting two parallel cytogenetic cultures with 12-O-tetradecanoly-phorpol-13-acetate (TPA) and IL2+DSP30 as a mitogen to detect complex karyotypes (CKs) in chronic lymphocytic leukemia (CLL). However, studies comparing CK detection concordance between both methods in the same cohort are lacking. Herein, we evaluated the performance of two parallel cultures in a CLL cohort of 255 patients, specifically comparing CK detection (globally and in each individual patient). The CK detection rates and their prognostic impacts were similar for both mitogens. However, nearly one-third of CKs were only identified in one culture, mainly due to the detection of a normal karyotype or no metaphases in the other. In summary, the assessment of parallel cytogenetic cultures is the best strategy to detect CKs in CLL. Nonetheless, as IL2+DSP30 achieved the best performance, it should be prioritized above TPA if a single analysis is required to optimize cytogenetic assessment in routine practice. Current CLL guidelines recommend a two parallel cultures assessment using TPA and IL2+DSP30 mitogens for complex karyotype (CK) detection. Studies comparing both mitogens for CK identification in the same cohort are lacking. We analyzed the global performance, CK detection, and concordance in the complexity assessment of two cytogenetic cultures from 255 CLL patients. IL2+DSP30 identified more altered karyotypes than TPA (50 vs. 39%, p = 0.031). Moreover, in 71% of those abnormal by both, IL2+DSP30 identified more abnormalities and/or abnormal metaphases. CK detection was similar for TPA and IL2+DSP30 (10% vs. 11%). However, 11/33 CKs (33%) were discordant, mainly due to the detection of a normal karyotype or no metaphases in the other culture. Patients requiring treatment within 12 months after sampling (active CLL) displayed significantly more CKs than those showing a stable disease (55% vs. 12%, p < 0.001). Disease status did not impact cultures' concordance (κ index: 0.735 and 0.754 for stable and active). Although CK was associated with shorter time to first treatment (TTFT) using both methods, IL2+DSP30 displayed better accuracy than TPA for predicting TTFT (C-index: 0.605 vs. 0.580, respectively). In summary, the analysis of two parallel cultures is the best option to detect CKs in CLL. Nonetheless, IL2+DSP30 could be prioritized above TPA to optimize cytogenetic assessment in clinical practice. [ABSTRACT FROM AUTHOR]

We report an interesting case of a T lymphoblastic lymphoma (T‐LBL) with uncommon CD20 expression. Immunophenotype analysis showed TdT expression with positivity of CD3 and CD7 among other T‐lineage markers. Other non‐T markers such as CD79a or myeloid‐associated antigens were negative. Molecular studies were performed evidencing clonal rearrangements for gamma and beta chain T cell receptor were clonal in the lymph node biopsy. Cytogenetic analysis showed deletions in CDKN2A and NOTCH2 genes. CD20 when present in T‐LBL can lead to a false diagnosis of B‐LBL. In this scenario, analysis of rearrangements of both immunoglobulin heavy chain B cell receptor and rearrangement of the T cell receptor can be very helpful. [ABSTRACT FROM AUTHOR]

Chronic lymphocytic leukemia (CLL) is characterized by a highly variable clinical course. Del(11q) and del(17p), routinely studied by conventional G-banding cytogenetics (CGC) and fluorescence in situ hybridization (FISH), have been related to progression and shorter overall survival. Recently, array-based karyotyping has gained acceptance as a high-resolution new tool for detecting genomic imbalances. The aim of the present study was to compare genomic arrays with CGC and FISH to ascertain whether the current techniques could be substituted in routine procedures. We analyzed 70 patients with CLL using the Cytogenetics Whole-Genome 2.7M Array and CytoScan HD Array (Affymetrix), CGC and FISH with the classical CLL panel. Whereas 31.4% and 68.6% of patients presented abnormalities when studied by CGC and FISH, respectively, these rates increased when arrays were also analyzed (78.6% and 80%). Although abnormality detection is higher when arrays are applied, one case with del(11q) and three with del(17p) were missed by genomic arrays due to their limited sensitivity. We consider that the complete substitution of CGC and FISH by genomic arrays in routine laboratories could negatively affect the management of some patients harboring 11q or 17p deletions. In conclusion, genomic arrays are valid to detect known and novel genomic imbalances in CLL, but should be maintained as a complementary tool to the current techniques. [ABSTRACT FROM AUTHOR]

Abstract: Small cell lung cancer (SCLC) shows an excellent sensitivity to chemotherapy, but commonly develops resistance after a few months. An early identification of a genomic marker in drug discovery may help to select patients who would respond to treatment in clinical trials. Herein, we characterized the parental NCI-H69 (sensitive) and NCI-H69AR (anthracycline-resistant) cell lines by G-banding and spectral karyotyping (SKY). In the H69 cell line, SKY allows us to redefine three alterations that are not well characterized by G-banding and to confirm seven. For H69AR, SKY redefined 10 chromosomal alterations and confirmed four observed by G-banding. Fluorescence in situ hybridization confirmed the amplification of the MYCN gene (dmin or hsr) in these two cell lines, although only the H69AR cell line showed MYCN amplification in the form of homogeneously staining regions. It should be noted that a new derivative chromosome appears in the H69AR cell line, a der(16)t(3;16;18;5;18), characterized by SKY as showing 18q amplification. Amplification of genes located in this region may correlate with resistance to anticancer therapies. We suggest that the 18q marker may have a broader application in SCLC. In conclusion, SKY provides a useful complementary technique to routine cytogenetics for the accurate characterization of SCLC cell lines and could provide some relevant information concerning regions involved in chemoresistance. [Copyright &y& Elsevier]

Abstract: Splenic marginal zone lymphoma (SMZL) is a B-cell lymphoproliferative disorder with characteristic clinical, immunophenotypic, cytological and histological features. Some karyotypic abnormalities have been related to this disorder and most of them are usually complex and difficult to define. The aim of present study was to characterize new chromosomal aberrations involved in this disease. We performed conventional banding cytogenetics and Spectral Karyotyping (SKY) technique in 23 patients diagnosed with SMZL having a complex karyotype among a series of 160 SMZL cases. Del(7)(q22–q32) and trisomy 3/3q were the most common chromosomal aberrations. In addition, new translocations involving chromosomes 3, 6, 8, 9, 12 and 14q32 region were detected. [Copyright &y& Elsevier]

Here, we report a 72-year-old male patient with acute myeloid leukemia (AML) without maturation. Cytogenetic study of a bone marrow culture revealed the following karyotype: 47,XX,+21,+i(21)(q10)×2. Fluorescence in situ hybridization study with a locus specific probe for 21q22 verified a pentasomy of 21q as a sole clonal cytogenetic abnormality. To our knowledge, this is the first report of pentasomy 21q in AML without Down syndrome. [Copyright &y& Elsevier]

Presents a study which discussed cases of splenic marginal zone B-cell lymphoma. Morphological data on the cytogenetic abnormality; Medical history of patients affected by the disease; Translocations of 14q32 gene.

Abstract: Follicular lymphoma (FL) is one of the most common non-Hodgkin lymphomas (NHL). Translocation t(14;18)(q32;q21) involving IGH and BCL2 genes represents its genetic hallmark. We present six cases of a series of 75 well diagnosed FL patients in which variant fluorescence in situ hybridization (FISH) patterns for this rearrangement were found. Moreover, G-banding cytogenetics and polymerase chain reaction (PCR) methods were unable to detect t(14;18)(q32;q21). According to our results, FISH is the best technique to define variant rearrangements of IGH/BCL2 genes and is important to detect it in cases with non-conclusive FL characteristics to avoid misdiagnosis with other NHL. [ABSTRACT FROM AUTHOR]

Abstract: Abnormalities of chromosome 5 are common aberrations in myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML), being del(5q) the most frequent. In contrast, monosomy 5 is not so frequent and, usually, is associated with complex karyotypes, conferring poor prognosis. The aim of this study was to analyze, by FISH for 5q31 (EGR1), a series of 28 MDS and AML cases with monosomy 5 detected by G-banding. FISH results revealed deletion of 5q31 in 24 of them (85.7%) and monosomy 5 just in three. FISH for 5q31 can complement conventional cytogenetics and improve the karyotype definition, leading to a better diagnostic and prognostic stratification. [ABSTRACT FROM AUTHOR]

The cytogenetic and molecular cytogenetic characterization of the human cell line A-431 derived from a vulvar epidermoid carcinoma is presented. A combination of karyotyping, fluorescence in situ hybridization (FISH) with chromosome- and/or region-specific probes, M-FISH, RxFISH, and comparative genomic hybridization (CGH) analysis was used. Six marker chromosomes with rearrangements involving insertions of single or double nucleolar organizing regions (NORs) and/or homogeneously staining regions containing active and overexpressed NORs and regions of centromeric heterochromatin were found: der(6), der(7), der(17), der(21), dic(13;14), and dic(14;18). The chromosomal origin of 14 other marker chromosomes was elucidated. Amplification of the C-MYC oncogene at 8q24 was revealed in two marker chromosomes: dup(8)(q24) and der(15)t(8;15)(q22;p11). Confirming previous reports, amplification of the cyclin D1 gene within an abnormal chromosome 11, that is, der(11)t(7;11)(p15;q21), was also detected. Loss of the TP53 tumor suppressor gene was evidenced over two der(17). Good concordance was found among karyotyping, FISH analysis, and CGH. Although reasons for NOR amplification or ectopic location in the epidermal carcinoma A-431 cell line are not clear yet, our data suggest that these phenomena play a supporting role with regard to other amplified genes. Thus, the A-431 cell line would be an appropriate model to study the different mechanisms involved in human tumorigenesis. [Copyright &y& Elsevier]