Down syndrome in diverse populations.

Down syndrome is the most common cause of cognitive impairment and presents clinically with universally recognizable signs and symptoms. In this study, we focus on exam findings and digital facial analysis technology in individuals with Down syndrome in diverse populations. Photos and clinical information were collected on 65 individuals from 13 countries, 56.9% were male and the average age was 6.6 years (range 1 month to 26 years; SD = 6.6 years). Subjective findings showed that clinical features were different across ethnicities (Africans, Asians, and Latin Americans), including brachycephaly, ear anomalies, clinodactyly, sandal gap, and abundant neck skin, which were all significantly less frequent in Africans (P < 0.001, P < 0.001, P < 0.001, P < 0.05, and P < 0.05, respectively). Evaluation using a digital facial analysis technology of a larger diverse cohort of newborns to adults (n = 129 cases; n = 132 controls) was able to diagnose Down syndrome with a sensitivity of 0.961, specificity of 0.924, and accuracy of 0.943. Only the angles at medial canthus and ala of the nose were common significant findings amongst different ethnicities (Caucasians, Africans, and Asians) when compared to ethnically matched controls. The Asian group had the least number of significant digital facial biometrics at 4, compared to Caucasians at 8 and Africans at 7. In conclusion, this study displays the wide variety of findings across different geographic populations in Down syndrome and demonstrates the accuracy and promise of digital facial analysis technology in the diagnosis of Down syndrome internationally. © 2016 Wiley Periodicals, Inc.

Next-generation sequencing using a pre-designed gene panel for the molecular diagnosis of congenital disorders in pediatric patients.

BACKGROUND: Next-generation sequencing (NGS) has revolutionized genetic research and offers enormous potential for clinical application. Sequencing the exome has the advantage of casting the net wide for all known coding regions while targeted gene panel sequencing provides enhanced sequencing depths and can be designed to avoid incidental findings in adult-onset conditions. A HaloPlex panel consisting of 180 genes within commonly altered chromosomal regions is available for use on both the Ion Personal Genome Machine (PGM) and MiSeq platforms to screen for causative mutations in these genes. METHODS: We used this Haloplex ICCG panel for targeted sequencing of 15 patients with clinical presentations indicative of an abnormality in one of the 180 genes. Sequencing runs were done using the Ion 318 Chips on the Ion Torrent PGM. Variants were filtered for known polymorphisms and analysis was done to identify possible disease-causing variants before validation by Sanger sequencing. When possible, segregation of variants with phenotype in family members was performed to ascertain the pathogenicity of the variant. RESULTS: More than 97% of the target bases were covered at >20×. There was an average of 9.6 novel variants per patient. Pathogenic mutations were identified in five genes for six patients, with two novel variants. There were another five likely pathogenic variants, some of which were unreported novel variants. CONCLUSIONS: In a cohort of 15 patients, we were able to identify a likely genetic etiology in six patients (40%). Another five patients had candidate variants for which further evaluation and segregation analysis are ongoing. Our results indicate that the HaloPlex ICCG panel is useful as a rapid, high-throughput and cost-effective screening tool for 170 of the 180 genes. There is low coverage for some regions in several genes which might have to be supplemented by Sanger sequencing. However, comparing the cost, ease of analysis, and shorter turnaround time, it is a good alternative to exome sequencing for patients whose features are suggestive of a genetic etiology involving one of the genes in the panel.

De novo trisomy 12p in twin girls with different levels of mosaicism.

We report on a pair of twins with trisomy 12p diagnosed postnatally. The girls were referred for dysmorphism and global developmental delay and have been followed from 10 months of age. They have different levels of mosaicism for both buccal cells and lymphocytes. Although their phenotypic features were similar, there were different degrees of severity which correlate with the different levels of mosaicism.

An additional case of the recurrent 15q24.1 microdeletion syndrome and review of the literature.

We report a 9-year-old girl with 3 Mb interstitial deletion of chromosome 15q24 identified by oligonucleotide array comparative hybridization. She is of Chinese ancestry and shared some typical features of previously reported 15q24 deletion cases such as mild dysmorphism with developmental and speech delay. She also had mild hearing loss that was reported in one other case. We compared all 19 cases that are identified from array-CGH. The deletion occurred within an 8.3 Mb region from 15q23 to 15q24.3. The minimum overlapping deleted region is less than 0.5 Mb from 72.3 Mb to 72.7 Mb. The functions of the nine annotated genes within the region and how they might contribute to the microdeletion phenotype are discussed.

Use of deferiprone for iron chelation in patients with transfusion-dependent thalassaemia.

AIM: To conduct a retrospective case analysis of the clinical efficacy and adverse effects of deferiprone in our population. METHODS: All patients with transfusion-dependent thalassaemia at KK Hospital who have been on deferiprone were included in the study. Outcomes measured include the change in ferritin levels and cardiac T2* values during deferiprone therapy, and incidence of side effects. RESULTS: Thirty-three (47.1%) of the total cohort of 70 patients have been on deferiprone, out of which 26 were on combination therapy with desferrioxamine. Majority of the patients (76%) had stable cardiac iron load during deferiprone therapy, and four patients with moderate to severe cardiac iron load showed improvement. Ten patients (30.3%) had improvement in their ferritin levels. Three patients (9.1%) developed mild neutropenia at 3, 18 and 26 months, respectively, and two patients (6.1%) had agranulocytosis at 4 and 10 months, respectively. Their neutrophil counts improved spontaneously after cessation of deferiprone. Thrombocytopenia developed in 27.3% of the patients and was transient in majority (77.8%) of the patients. Five patients (15.2%) developed arthritis that improved after cessation of deferiprone therapy, and one patient had transient arthralgia that resolved spontaneously. Three patients (9.1%) had nausea and abdominal pain. CONCLUSION: Deferiprone effectively reduced or stabilised cardiac iron load in our patients. Thrombocytopenia, arthropathy, neutropenia and agranulocytosis are the most important side effects. It is recommended that patients on deferiprone have their full blood counts monitored weekly for the first year of therapy and subsequently fortnightly as long as they are on deferiprone.

Resilience: enhancing well-being through the positive cognitive triad.

The present study tested whether the relationships among resilience, life satisfaction, and depression could be explained by positive views toward the self, the world, and the future (positive cognitive triad). Structural equation modeling and mediation analyses were conducted based on 1,419 college students in Hong Kong. The model of positive cognitive triad as mediator between resilience and well-being fit the data (comparative fit index = .94, Tucker-Lewis index = .93, root-mean-square error of approximation = .08). Findings showed resilience to be significantly related to positive cognitions about the self, the world, and the future. Individuals who had higher level of resilience held significantly more positive cognitions and reported significantly higher levels of life satisfaction and lower levels of depression. The utility of the positive cognitive triad as the mechanism through which resilience enhances well-being was supported. Applications in cultivating resilience and positive cognitions in counseling services are discussed.

Radiation oncology training in Singapore - A non-Australasian RANZCR training site.

The Radiation Oncology Department at The National Cancer Institute, Singapore (NCIS) and the Royal Australian and New Zealand College of Radiology (RANZCR) has had a well-established relationship that began as a partnership to grow a pool of local radiation oncologists to meet a nation's demand for radiotherapy services. This journey has surpassed its initial aims and now has produced a generation of radiation oncologists leading a national cancer institute. We recount the history and progress of this partnership here, as well as the unique success of its product; the only RANZCR-accredited radiation oncology training site outside of Australia and New Zealand since 2002. We outline the mutual benefits through many years of collaboration and deliberate efforts to grow the partnership. We also outline the distinctive specialist training path that our trainees take to meet both the local accreditation body as well as the RANZCR requirements.

Genetic landscape of congenital disorders in patients from Southeast Asia: results from sequencing using a gene panel for Mendelian phenotypes.

OBJECTIVE: To test the utility and diagnostic yield of a medical-exome gene panel for identifying pathogenic variants in Mendelian disorders. METHODS: Next-generation sequencing was performed with the TruSight One gene panel (targeting 4813 genes) followed by MiSeq sequencing on 216 patients who presented with suspected genetic disorders as assessed by their attending physicians. RESULTS: There were 56 pathogenic and 36 likely pathogenic variants across 57 genes identified in 87 patients. Causal mutations were more likely to be truncating and from patients with a prior clinical diagnosis. Another 18 promising variants need further evaluation for more evidence to meet the requirement for potential upgrade to pathogenic. Forty-five of the 92 clinically significant variants were novel. CONCLUSION: The 40.3% positive yield compares favourably with similar studies using either this panel or whole exome sequencing, demonstrating that large gene panels could be a good alternative to whole exome sequencing for quick genetic confirmation of Mendelian disorders.

Singapore Undiagnosed Disease Program: Genomic Analysis aids Diagnosis and Clinical Management.

OBJECTIVE: Use next-generation sequencing (NGS) technology to improve our diagnostic yield in patients with suspected genetic disorders in the Asian setting. DESIGN: A diagnostic study conducted between 2014 and 2019 (and ongoing) under the Singapore Undiagnosed Disease Program. Date of last analysis was 1 July 2019. SETTING: Inpatient and outpatient genetics service at two large academic centres in Singapore. PATIENTS: Inclusion criteria: patients suspected of genetic disorders, based on abnormal antenatal ultrasound, multiple congenital anomalies and developmental delay. EXCLUSION CRITERIA: patients with known genetic disorders, either after clinical assessment or investigations (such as karyotype or chromosomal microarray). INTERVENTIONS: Use of NGS technology-whole exome sequencing (WES) or whole genome sequencing (WGS). MAIN OUTCOME MEASURES: (1) Diagnostic yield by sequencing type, (2) diagnostic yield by phenotypical categories, (3) reduction in time to diagnosis and (4) change in clinical outcomes and management. RESULTS: We demonstrate a 37.8% diagnostic yield for WES (n=172) and a 33.3% yield for WGS (n=24). The yield was higher when sequencing was conducted on trios (40.2%), as well as for certain phenotypes (neuromuscular, 54%, and skeletal dysplasia, 50%). In addition to aiding genetic counselling in 100% of the families, a positive result led to a change in treatment in 27% of patients. CONCLUSION: Genomic sequencing is an effective method for diagnosing rare disease or previous 'undiagnosed' disease. The clinical utility of WES/WGS is seen in the shortened time to diagnosis and the discovery of novel variants. Additionally, reaching a diagnosis significantly impacts families and leads to alteration in management of these patients.

International reproducibility of single breathhold T2* MR for cardiac and liver iron assessment among five thalassemia centers.

PURPOSE: To examine the reproducibility of the single breathhold T2* technique from different scanners, after installation of standard methodology in five international centers. MATERIALS AND METHODS: Up to 10 patients from each center were scanned twice locally for local interstudy reproducibility of heart and liver T2*, and then flown to a central MR facility to be rescanned on a reference scanner for intercenter reproducibility. Interobserver reproducibility for all scans was also assessed. RESULTS: Of the 49 patients scanned, the intercenter reproducibility for T2* was 5.9% for the heart and 5.8% for the liver. Local interstudy reproducibility for T2* was 7.4% for the heart and 4.6% for the liver. Interobserver reproducibility for T2* was 5.4% for the heart and 4.4% for the liver. CONCLUSION: These data indicate that T2* MR may be developed into a widespread test for tissue siderosis providing that well-defined and approved imaging and analysis techniques are used.

Amelioration of oxidative stress in red blood cells from patients with beta-thalassemia major and intermedia and E-beta-thalassemia following administration of a fermented papaya preparation.

In beta-hemoglobinopathies, such as beta-thalassemia (thal) and sickle cell anemia, the primary defects are mutations in the beta-globin gene. However, many aspects of the pathophysiology are mediated by oxidative stress. Fermented papaya preparation (FPP), a natural health food product obtained by biofermentation of carica papaya, has been shown to limit oxidative stress both in vitro and in vivo. We studied the effect of FPP on two groups of beta-thal patients: beta-thal, major and intermedia, (in Israel) and E-beta-thal (in Singapore). The results indicated that in both groups FPP treatment increased the content of reduced glutathione (GSH) in red blood cells (RBC), and decreased their reactive oxygen species (ROS) generation, membrane lipid peroxidation, and externalization of phosphatidylserine (PS), indicating amelioration of their oxidative status, without a significant change in the hematological parameters. Since the turnover of the erythron is relatively slow, it is possible that longer duration of treatment, probably with the addition of an iron chelator, is required in order to achieve the latter goals.

Identification of KMT2D and KDM6A variants by targeted sequencing from patients with Kabuki syndrome and other congenital disorders.

Kabuki syndrome (KS) is a rare congenital disorder characterized by distinctive facies, postnatal growth deficiency, cardiac defects and skeletal anomalies. Studies have determined that pathogenic variants of the lysine-specific methyltransferase 2D (KMT2D) and lysine-specific demethylase 6A (KDM6A) genes are the major causes of KS. The two genes encode different histone-modifying enzymes that are found in the same protein complex that is critical for cell differentiation during development. Here we report the results from next-generation sequencing of genomic DNA from 13 patients who had a clinical diagnosis of KS based on facial dysmorphism and other KS-specific cardinal phenotypes. Nine of the 13 patients were confirmed to be carrying heterozygous pathogenic KMT2D variants, seven of which were truncating and two were missense substitutions. Overall, we uncovered 11 novel variants - nine in KMT2D and two in KDM6A. Seven of the novel variants (all KMT2D) were likely causative of the KS phenotype. Our study expands the number of naturally occurring KMT2D and KDM6A variants. The discovery of novel pathogenic variants will add to the knowledge on disease-causing variants and the relevance of missense variants in KS.

Further delineation of CDC45-related Meier-Gorlin syndrome with craniosynostosis and review of literature.

Meier-Gorlin syndrome (MGS) is a rare autosomal recessive disorder characterized by the triad of short stature, microtia and absent or small patellae. We report on a patient with MGS secondary to biallelic mutations in CDC45 detected on whole exome sequencing (WES). Patients with MGS caused by mutations in CDC45 display a distinct phenotype characterized by craniosynostosis and anorectal malformation. Our patient had craniosynostosis, anorectal malformation and short stature, but did not have the microtia or patella hypoplasia. Our report also highlights the value of WES in aiding diagnosis of patients with rare genetic diseases. In conclusion, our case report and review of the literature illustrates the unique features of CDC45-related MGS as well as the benefits of WES in reducing the diagnostic odyssey for patients with rare genetic disorders.

Resilience Style Questionnaire: Development and Validation Among College Students and Cardiac Patients in Hong Kong.

The present research aims to develop and validate a measure of resilience that reflects the influence of Confucian philosophies and Chinese cultural lay beliefs. Based on a representative sample of 1,419 college students from universities and a clinical sample of 214 cardiac patients in Hong Kong, reliability, construct validity, and criterion validity of the Resilience Style Questionnaire (RSQ) were examined. A two-factor structure of the RSQ was explored and validated in both samples. Results showed that the two factors of the RSQ (i.e., perseverance and optimistic approach to life) were significantly associated with a variety of mental health indicators in both samples. Furthermore, the RSQ explained additional variances above and beyond those explained by the Ego-Resiliency Scale, the Sense of Coherence Scale (SOC), and the Connor-Davidson Resilience Scale in multiple mental health indicators among college students and cardiac patients. These findings showed that the RSQ is a reliable and valid tool in assessing resilience among Chinese and other groups influenced by Confucianism.

A review of whole brain radiotherapy outcomes in a high epidermal growth factor receptor mutation rate population: Does QUARTZ apply in Asia?

AIM: Whole brain radiotherapy (WBRT) is commonly used to treat brain metastases (BM) from nonsmall cell lung cancer (NSCLC). Its utility is increasingly being questioned after a recent randomized trial (QUARTZ) showed that its omission did not significantly impact the survival or quality of life of their patients recruited from UK and Australian centers. We report the patient characteristics and survival outcomes of our local population in comparison with theirs. METHODS: Medical records of patients who received WBRT in two tertiary hospitals over 18 months were reviewed. Characteristics and survival outcomes of patient with NSCLC receiving WBRT for the first time were evaluated. Patients with prior excision of BM or stereotactic radiotherapy were excluded. Treatment details including radiotherapy dose and use of tyrosine kinase inhibitors (TKIs) were recorded. RESULTS: Between January 2015 and June 2016, 116 patients with NSCLC received WBRT for their BM. Their median age was 65 years (range, 36-85) and median follow-up duration was 110 days (range, 14-840). A total of 102 (88%) patients had their driver mutation tested of which 59 (58%) were epidermal growth factor receptor (EGFR) mutants. Factors predicting for better survival were female gender (P < .001), EGFR mutant receiving TKIs (P = .013), prescription other than 20 Gray in five fractions (P = .003), and presence of more than four BM (P = .001). CONCLUSION: Our patients appear to be considerably different from those recruited into the QUARTZ trial. Further prospective studies should be done to evaluate the value of WBRT in our population.

The spectrum of genetic variants and phenotypic features of Southeast Asian patients with Noonan syndrome.

BACKGROUND: Noonan syndrome (NS) is an autosomal dominant disorder that belongs to a group of developmental disorders called RASopathies with overlapping features and multiple causative genes. The aim of the study was to identify mutations underlying this disorder in patients from Southeast Asia and characterize their clinical presentations. METHODS: Patients were identified from the hospital's Genetics clinics after assessment by attending clinical geneticists. A targeted gene panel was used for next-generation sequencing on genomic DNA extracted from the blood samples of 17 patients. RESULTS: Heterozygous missense variants were identified in 13 patients: eight were in PTPN11, three in SOS1, and one each in RIT1 and KRAS. All are known variants that have been reported in patients with NS. Of the 13 patients with identified variants, 10 had short stature, the most common feature for NS. Four of the eight patients with PTPN11 variants had atrial septal defect. Only two had pulmonary stenosis which is reported to be common for PTPN11 mutation carriers. Another two had hypertrophic cardiomyopathy, a feature which is negatively associated with PTPN11 mutations. CONCLUSIONS: Our study provides the mutation and phenotypic spectrum of NS from a new population group. The molecular testing yield of 76% is similar to other studies and shows that the targeted panel approach is useful for identifying genetic mutations in NS which has multiple causative genes. The molecular basis for the phenotypes of the remaining patients remains unknown and would need to be uncovered via sequencing of additional genes or other investigative methods.

Multi-center transferability of a breath-hold T2 technique for myocardial iron assessment.

BACKGROUND: Cardiac iron overload is the leading cause of death in thalassemia major and is usually assessed using myocardial T2* measurements. Recently a cardiovascular magnetic resonance (CMR) breath-hold T2 sequence has been developed as a possible alternative. This cardiac T2 technique has good interstudy reproducibility, but its transferability to different centres has not yet been investigated. METHODS AND RESULTS: The breath-hold black blood spin echo T2 sequence was installed and validated on 1.5T Siemens MR scanners at 4 different centres across the world. Using this sequence, 5-10 thalassemia patients from each centre were scanned twice locally within a week for local interstudy reproducibility (n = 34) and all were rescanned within one month at the standardization centre in London (intersite reproducibility). The local interstudy reproducibility (coefficient of variance) and mean difference were 4.4% and -0.06 ms. The intersite reproducibility and mean difference between scanners were 5.2% and -0.07 ms. CONCLUSION: The breath-hold myocardial T2 technique is transferable between Siemens scanners with good intersite and local interstudy reproducibility. This technique may have value in the diagnosis and management of patients with iron overload conditions such as thalassemia.

Chemoradiotherapy versus chemotherapy for locally advanced unresectable pancreatic cancer: A systematic review and meta-analysis.

PURPOSE: To determine the benefit of adding radiotherapy (RT) to chemotherapy for patients with locally advanced unresectable pancreatic cancer (LAUPC). METHODS: We searched MEDLINE for comparative studies comparing chemoradiotherapy with chemotherapy for patients with LAUPC. We performed the meta-analysis with random effects model. The primary outcome was overall survival (OS); secondary outcomes include progression-free survival (PFS) and adverse events (AE). RESULTS: We found five randomized (RCT) and three observational studies (OBS) including 830 patients. For RCTs, the addition of radiotherapy did not improve PFS (hazard ratio [HR] 0.90; 95% confidence interval [CI], 0.74-1.10; P = 0.30; I2   =  11%,) or OS (HR 0.87; 95% CI, 0.63-1.21; P = 0.41; I2 = 67%,) and was associated with increased grade 3 or 4 gastrointestinal AE. In contrast, OBS reported an improvement in PFS (HR 0.58; 95% CI, 0.37-0.92; P = 0.02; I2 = 32%) and OS (HR 0.48; 95% CI, 0.35-0.60; P < 0.0001; I2 = 6%). CONCLUSION: The addition of radiotherapy did not improve the OS and PFS in RCTs. The divergence in results seen in OBS may be due to imbalance in baseline characteristics. Further research incorporating biomarkers may help to better select patients who will benefit from RT.

Outcomes of neoadjuvant chemoradiotherapy followed by total mesorectal excision surgery for locally advanced rectal cancer: a single-institution experience.

INTRODUCTION: Neoadjuvant chemoradiotherapy (CRT) followed by total mesorectal excision (TME) surgery for locally advanced rectal cancer has been shown to improve local control and reduce toxicity, as compared to adjuvant CRT. We reported the outcomes of our patients with locally advanced rectal cancer treated at National University Hospital, Singapore. METHODS: From April 2002 to December 2014, 117 patients with T3/4, N0/+, M0 rectal cancer received neoadjuvant CRT followed by TME surgery. The treatment regimen comprised a total radiotherapy dose of 50.4 Gy in 28 daily fractions delivered concurrently with 5-fluorouracil or capecitabine chemotherapy over 5.5 weeks. All patients were planned for TME surgery. Local control, disease-free survival, overall survival and treatment toxicities were analysed. RESULTS: Median follow-up was 34 (range 2-122) months. 11.5% (13/113) of patients achieved a pathological complete response (pCR) and 72.6% (85/117) had either tumour or nodal downstaging following neoadjuvant CRT. 5.2% (5/96) of patients had Grade 3 acute toxicities (dermatitis and diarrhoea) and 3.1% (3/96) had Grade 3 late toxicities (fistula and stricture). There was no Grade 4 toxicity noted. The five-year local recurrence, disease-free survival and overall survival rates were 4.5%, 65.7% and 80.6%, respectively. Multivariate analysis showed that nodal positivity was a predictor of poor disease-free survival and poor overall survival. Tumour downstaging and pCR did not improve outcomes. CONCLUSION: Our outcomes were comparable to internationally published data, and this treatment regimen remains the standard of care for locally advanced rectal cancer in our local population.