Non-invasive Prenatal Testing, What Patients Do Not Learn, May Be Due to Lack of Specialist Genetic Training by Gynecologists and Obstetricians?

Platforms for “non-invasive prenatal testing” (NIPT), or also referred to as “non-invasive prenatal screening” (NIPS) have been available for over 10 years, and are the most recent tools available to obtain information about genetic condition(s) of an unborn child. The highly praised advantage of NIPT-screening is that results can provide early hints on the detection of fetal trisomies and gonosomal numerical aberrations as early as the 10th week of gestation onward, without any need for invasive procedures, such as amniocenteses or alternatives. Understandably, the public along with gynecologists and obstetricians eagerly await these early test results. Their general hope for normal (=negative) test results is also justified, as in >95% of the tested cases such an outcome is to be expected. However, pregnant women can be disappointed and confused, particularly regarding the genetic information and proposed care when the results are positive, and these emotions are also common with false-positive and false-negative NIPT results. Finally, such concerns in understanding the advantages and limitations of this routinely ordered screening tool end up at Clinical Geneticists and Genetic counselors. In this review, general background on NIPT, differences of NIPT platforms, advantages and limitations of NIPT, as well as consequences of insufficient counseling before and after NIPT are summarized. To provide comprehensive care in all pregnancies situations, professionals need a careful attitude toward offering NIPT along with specially training and qualifications in counseling for these procedures. Often it is gynecologists and obstetricians who discuss the use of NIPT with patients; however, although these physicians have a highly qualified background and knowledge in their respective specialty area(s), they may lack specific training on the interpretation of NIPT-screening results. These potential knowledge gaps must be closed quickly and comprehensively by the corresponding scientific societies to ensure optimal patient care.

Chromosomal defects and survival in patients with adult T-cell leukemia/lymphoma after allogeneic HSCT

Adult T-cell leukemia/lymphoma (ATL) cells frequently exhibit chromosomal abnormalities, including numerical aberrations and structural defects. However, no studies have examined the correlation between these abnormalities and survival in patients with ATL after allogeneic HSCT (allo-HSCT). In this study, 300 patients with ATL (median age, 55 years; range, 24-74) who were registered in a Japanese nationwide registry database were analyzed. The majority (n = 183) had acute ATL. Specimens for chromosomal analysis were collected from bone marrow (n = 166), lymph nodes (n = 86), peripheral blood (n = 41), and other locations (n = 7). In survival analyses, breakpoints at 2q (hazard ratio [HR], 1.63; 95% confidence interval [CI], 1.12-2.38; P = .012) and 5q (HR, 2.18; 95% CI, 1.25-3.80; P = .006) were significantly poor prognostic factors for overall survival (OS). In terms of ATL-related death, loss of chromosome 14 and breakpoints at 3p, 1q, 5q, and 6q were extracted as significantly poor prognostic factors. Moreover, complex karyotypes were associated with ATL-related death. This study of the survival impact of chromosomal abnormalities in patients with ATL after allo-HSCT demonstrated that several structural breakpoints were independent risk factors for OS and ATL-related death.

Aneuploidy Analysis of 5740 Referral Cases: A Triennial Report

Background and Objectives: Aneuploidy is one of the major concerns to cause genetic anomalies. This condition is mostly related to addition and/or deletion with respect to set(s) of chromosomes. Here, we report an analysis of 5740 referral cases during three consecutive years (2015 – 2018) from our Diagnostic Research Center, Ahmedabad for aneuploidy pattern. Methodologies: The patients were asked to fill the necessary forms and their blood (5ml) was drawn for chromosomal studies using the Karyotyping following International System for Human Cytogenetic Nomenclature (ISCN) manual. Results: The data revealed the numerical aberrations for only aneuploidy detected was (3.7%; 211/5740). In this report, constitutional (c) autosomal aneuploidy was 75% (158/211). The total mosaic cases were nine (9/211) comprising constitutive (2) and acquired (7) aneuploidy cases. In autosomal aneuploidy, cT21 was higher (96%; 152/158) than others (4%; 6/158) comparatively. Among cT21 (152), males (76%; 115/152) were more affected than females (24%; 37/152). These statistical data also revealed that acquired chromosomal aneuploidy (leukemia) possessed (25%; 53/211); with more mosaic cases (7/211). Conclusion: Couples with such conditions are eligible for genetic tests and counseling as well as new strategies are urgently to be undertaken by governmental organizations (GOs) and non-governmental organizations (NGOs) for affected families with better personalized and informed decision making. The significance of these data is thus discussed in relation to genetic disorders caused by constitutional and acquired aneuploidy of leukemic blood in this report.

Chromosome Aberrations Produced by Mestranol in Human Lymphocyte Cultures

In this investigation, the genotoxic properties of mestranol were examined in vitro. Human lymphocyte cultures were exposed for 72 h to mestranol at concentrations of 7.5, 15 and 30 µg/g. The genotoxic effects of the chemosterilant were assessed by numerical and structural chromosome aberrations. Mestranol induced certain genotoxic effects in human lymphocytes. There was a dose-dependent significant (p<0.01) increase in the number of numerical aberrations in comparison to the control, but without significant differences (p>0.05) between the doses applied. Further, structural aberrations increased significantly (p<0.01) in the presence of mestranol, being most frequent in cultures exposed to the highest mestranol dose. The frequency of Robertsonian translocations increased significantly only in cultures treated with mestranol at concentration of 30 µg/g in comparison both with the control (p<0.01) and the lowest chemosterilant dose (p<0.01). There were significant differences (p<0.01) in the levels of chromosome gaps and fragments compared to Robertsonian translocations, whilst the frequencies between gaps and fragments were not significantly different (p>0.05).

Comparison of diagnostic methodologies to detect chromosomal abnormalities.

e14617 Background: Traditional technologies such as cytogenetics, FISH, and microarray (CGH) are utilized in most clinical laboratories. Next-Generation Sequencing (NGS) is a relatively new tool to evaluate the cancer genome. Applications of this method include assessing single nucleotide variants (SNVs), indel mutations, and copy number variations (CNVs), including some large chromosomal deletions or gains. Methods: We used a custom Discovery+LOH NGS panel (Agilent, Santa Clara) to determine the utility of NGS in detecting CNV and loss of heterozygosity (LOH) events. Thirty six patients with known DNA structural abnormalities and hematologic disease were tested using cytogenetics, the NGS panel, and CytoScan HD microarray. Results: As shown in the table, NGS detected all abnormalities reported by CGH. NGS failed to detect 14 abnormalities reported by cytogenetics, but detected additional gains and losses from small chromosomal regions as well as LOH events. Notably, NGS found a 16p loss, but cytogenetics detected a full chr16 loss and a 7q loss. NGS detected an 11p loss which was missed by cytogenetics. Table: Comparison of Detection by Methodologies. Conclusions: This study highlights the benefits and limitations of each method using clinical samples with hematologic disease. Cytogenetics provided a gross view of a karyotype, but lacked resolution to detect small aberrations and LOH events. NGS provided high resolution of numerical aberrations and detected LOH events, but was unable to detect some gain and loss events. In examining those missed events, < 30% abnormal cells were found in those specimens, possibly explaining the reduced sensitivity. Importantly, we found two significant discrepant chromosomal aberrations between cytogenetics and NGS. This may result from cytogenetic culture where preferential growth of cells influence the detection of a chromosome gain or loss. These findings suggest advantages in assessing chromosomal abnormalities using NGS in coordination with more traditional methods to improve diagnostic and prognostic determination to assist in treatment selection.[Table: see text]

Fetal chromosomal anomalies in southeast Serbia - single center cohort retrospective study

Congenital anomalies are the cause of prenatal death in 20-25% of the cases, while 3% of children are born with a malformation of varying size. Many of these anomalies can be detected before birth using different non-invasive and invasive prenatal diagnostic tests. This study was used to determine the distribution of genetic disorders in relation to the age of the mother, the frequency of aberrations and to study the effects and importance of prenatal diagnosis in South Serbia. Prenatal diagnostics was performed at the Pediatric Clinic within the Clinical Center of Nis. This retrospective study included a group of 8830 pregnant women, aged between 18 and 47 years during the period from 2004 to 2017. Amniocentesis was performed between the 16th and 18th week of pregnancy and involved the aspiration of 20 ml of amniotic fluid. Isolated cells were cultured in a medium that stimulates cell growth for 10 days. After cytogenetic processing, the obtained karyotype was analyzed using G-banding techniques. In 8830 samples of amniotic fluid cell cultures, 198 karyotypes with chromosomal aberrations were found - 179 with numerical aberrations and 19 with structural aberrations such as translocations, inversions and deletions. There were 85 karyotypes with autosomal numerical aberrations and 32 karyotypes with sex chromosome numerical aberrations. The most frequent one was trisomy 21 (106 cases). The highest number of autosomal numerical aberrations, 84%, was found in pregnancies where maternal age was above 30 years. Preventive action, advice, education and availability of prenatal diagnosis can lead to a significant reduction in the number of children born with various malformations.

Understanding the Role of Hyperdiploidy in Burkitt Lymphoma of Childhood: Biological and Clinical Correlates

Background: Burkitt lymphoma (BL) is the most common high-grade lymphoma in childhood. BL is typically associated with rearrangement of the MYC gene, on 8q24 chromosome region, and often accompanied by other aberrations, some of which are known to adversely influence the clinical behavior and prognosis of the disease. However, hyperdiploidy, though frequently detected cytogenetically, has not been convincingly linked to specific biological and clinical features of BL. We present here our experience with 8 pediatric hyperdiploid BL cases detected with molecular cytogenetics in the course of routine genetic investigation. Materials and methods: The study included 44 children (35 boys, 9 girls), aged 1 to 15 years (median 6), diagnosed with histologically documented BL. In all cases, interphase FISH was performed on infiltrated bone marrow smears or touch imprints from samples of involved sites. FISH probes employed included sets of the detection MYC, BCL2, BCL6, IGH, IGK, and IGL rearrangement, -17/del(17p13), -9/(del9p21) and del(13q14)/del(13q34). Cases with over-representation of any of the chromosome regions targeted were further tested with the use of the appropriate centromeric/chromosome enumeration probe. Thus, this line of testing allowed for the detection of numerical aberrations of chromosomes 2, 3, 8, 9, 13, 14, 17, 18 and 22. Over-representation of at least three chromosomes, without evidence for any monosomy, was considered a hyperdiploidy criterion. Results: MYC was found rearranged in all cases, in 38 together with IGH and in 6 of them with IGK or IGL rearrangment. 17p-, 13q- and 9p- were detected in 3, 4 and 2 cases, respectively. There were no cases with BCL2 or BCL6 rearrangements. With a median follow-up of 5.5 years, 4 relapses/deaths were observed. Hyperdiploidy was detected in 8 patients (18.2%), with involvement of at least 7 of the 9 chromosomes tested, at the level of trisomy to hexasomy. Hyperdiploid and non-hyperdiploid cases were comparable with regard to sex and age. However, all cases with IGK/IGL involvement, 17p-, 13q- or 9p-, and relapse/death were seen exclusively in the non-hyperdiploid group. Conclusions: From the observations on this small group of patients, it seems that hyperdiploidy is rather common in childhood BL and, perhaps, represents a distinct clonal evolution pathway of the standard t(8;14)+ disease. It appears to be associated with a favorable prognosis. Further study on a larger number of cases is required to fully elucidate the clinical significance of the hyperdiploidy and whether it may be used as a marker of "low-risk" disease, by analogy to acute lymphoblastic leukemia. Disclosures Kattamis: Novartis: Consultancy, Honoraria; Vifor Pharma: Consultancy; CELGENE: Consultancy, Honoraria; ApoPharma: Honoraria.

Prognostic Significance of Cyclins A2, B1, D1, and E1 and CCND1 Numerical Aberrations in Oral Squamous Cell Carcinomas

We analysed the expression of cyclins A2, B1, D1, and E1 by immunohistochemistry and numerical aberrations in CCND1 gene by fluorescence in situ hybridization technique in 67 primary oral squamous cell carcinomas (OSCC). Cyclin A2 expression was observed in 54 (83.1%) tumours, cyclin D1 in 58 (89.2%), cyclin B1 in 39 (60%), and cyclin E in 21 (32.8%). CCND1 region analysis revealed 26 (43.3%) tumours with the presence of numerical aberrations which were correlated with cyclin D1 high expression (Rho = 0.48; p<0.001). Twenty-nine (45.3%) tumours were classified as high proliferative tumours assessed by Ki-67 protein expression and correlated with tumours with high expression of cyclin A2 (Rho = 0.30; p=0.016) and cyclin B1 (Rho = 0.37; p=0.003). In multivariate analysis for an overall five-year survival (OS), we found an adverse independent prognostic value for cyclin A2 high expression (p=0.031) and for advanced tumour stage (p<0.001). Our results confirm that several cyclins are commonly expressed in OSCC. CCND1 gene is abnormal in more than one-third of the cases and is frequently associated with cyclin D1 high expression. Moreover, cyclin A2 high expression is an independent indicator of worse OS suggesting that this protein may serve as a reliable biological marker to identify high-risk subgroups with poor prognosis.