Publications by authors named "Kai-Ren Ong"

Background: CDH1 (E-cadherin) genetic mutations are associated with a 30%-70% increased lifetime risk of hereditary diffuse gastric cancer (HDGC). Although prophylactic total gastrectomy (PTG) reduces long-term risk of gastric cancer, the associated morbidity and mortality remain unclear. This systematic review aims to characterise postoperative surgical outcomes in patients undergoing total gastrectomy.

View Article and Find Full Text PDF

Objectives: To report the long-term outcomes from a longitudinal psychosocial study that forms part of the 'Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted Screening in men at higher genetic risk and controls' (IMPACT) study. The IMPACT study is a multi-national study of targeted prostate cancer (PrCa) screening in individuals with a known germline pathogenic variant (GPV) in either the BReast CAncer gene 1 (BRCA1) or the BReast CAncer gene 2 (BRCA2).

Subjects And Methods: Participants enrolled in the IMPACT study were invited to complete a psychosocial questionnaire prior to each annual screening visit for a minimum of 5 years.

View Article and Find Full Text PDF
Article Synopsis
  • Scientists found that families with certain DNA repair problems have more new mutations passed down from parents to kids.
  • Parents with specific gene mutations had kids that had about 20-150 more mutations than normal, but most of these were in non-important parts of DNA.
  • The study suggests that while DNA repair issues lead to extra mutations, they probably won't cause any noticeable health problems for those kids.
View Article and Find Full Text PDF

Germline pathogenic variants (GPVs) in the cancer predisposition genes , , , , , , , and are identified in approximately 15% of patients with ovarian cancer (OC). While there are clear guidelines around clinical management of cancer risk in patients with GPV in , , , and , there are few guidelines on how to manage the more moderate OC risk in patients with GPV in , , and , with clinical questions about appropriateness and timing of risk-reducing gynaecological surgery. Furthermore, while recognition of and R as OC predisposition genes has been established for several years, an association with breast cancer (BC) has only more recently been described and clinical management of this risk has been unclear.

View Article and Find Full Text PDF

Background: Von Hippel-Lindau (VHL) disease is an inherited tumour predisposition syndrome and a paradigm for the importance of early diagnosis and surveillance. However, there is limited information on the "real world" management of VHL disease.

Methods: A national audit of VHL disease in the United Kingdom.

View Article and Find Full Text PDF
Article Synopsis
  • Lynch syndrome is a hereditary cancer syndrome linked to mutations in mismatch repair genes, increasing the risk for various cancers, especially colorectal and endometrial cancer, and recently identified as a risk factor for early-onset aggressive prostate cancer.
  • The IMPACT study, an international research project, is evaluating the effectiveness of prostate-specific antigen (PSA) screening among men aged 40-69 with and without these genetic variants to determine the incidence and characteristics of prostate cancer.
  • Initial findings from the first round of PSA screenings indicate differences in prostate cancer detection and characteristics between men with pathogenic variants compared to age-matched controls who do not carry these variants.
View Article and Find Full Text PDF

A 4-year-old boy presented with his mother to genetics in the 1980s, with a family history (FH) of macrocephaly and intellectual disability (ID). He remained undiagnosed until his mother developed multiple cancers and was diagnosed with Cowden syndrome (CS) in 2017, a rare, multisystem cancer predisposition syndrome. CS was then confirmed in multiple family members.

View Article and Find Full Text PDF

Background: Ovarian cancer risk in BRCA1 and BRCA2 mutation carriers has been shown to decrease with longer duration of oral contraceptive use. Although the effects of using oral contraceptives in the general population are well established (approximately 50% risk reduction in ovarian cancer), the estimated risk reduction in mutation carriers is much less precise because of potential bias and small sample sizes. In addition, only a few studies on oral contraceptive use have examined the associations of duration of use, time since last use, starting age, and calendar year of start with risk of ovarian cancer.

View Article and Find Full Text PDF
Article Synopsis
  • The study examined how polygenic risk scores (PRS) for breast and ovarian cancers relate to risks for women with BRCA1 and BRCA2 gene variants.
  • It used data from nearly 32,000 female carriers to evaluate different versions of BC and EOC PRS, finding that specific scores were strongly linked to cancer risk.
  • Results indicated stronger associations between certain PRS and cancer risks, with implications for understanding absolute risk differences among women in different PRS groups.
View Article and Find Full Text PDF

A BRCA2 prostate cancer cluster region (PCCR) was recently proposed (c.7914 to 3') wherein pathogenic variants (PVs) are associated with higher prostate cancer (PCa) risk than PVs elsewhere in the BRCA2 gene. Using a prospective cohort study of 447 male BRCA2 PV carriers recruited in the UK and Ireland from 1998 to 2016, we estimated standardised incidence ratios (SIRs) compared with population incidences and assessed variation in risk by PV location.

View Article and Find Full Text PDF

Pathogenic sequence variants (PSV) in or () are associated with increased risk and severity of prostate cancer. We evaluated whether PSVs in were associated with risk of overall prostate cancer or high grade (Gleason 8+) prostate cancer using an international sample of 65 and 171 male PSV carriers with prostate cancer, and 3,388 and 2,880 male PSV carriers without prostate cancer. PSVs in the 3' region of (c.

View Article and Find Full Text PDF

Background: Mutations in BRCA2 cause a higher risk of early-onset aggressive prostate cancer (PrCa). The IMPACT study is evaluating targeted PrCa screening using prostate-specific-antigen (PSA) in men with germline BRCA1/2 mutations.

Objective: To report the utility of PSA screening, PrCa incidence, positive predictive value of PSA, biopsy, and tumour characteristics after 3 yr of screening, by BRCA status.

View Article and Find Full Text PDF

Background: BRCA1 and BRCA2 mutations have been associated with prostate cancer (PCa) risk but a wide range of risk estimates have been reported that are based on retrospective studies.

Objective: To estimate relative and absolute PCa risks associated with BRCA1/2 mutations and to assess risk modification by age, family history, and mutation location.

Design, Setting, And Participants: This was a prospective cohort study of male BRCA1 (n = 376) and BRCA2 carriers (n = 447) identified in clinical genetics centres in the UK and Ireland (median follow-up 5.

View Article and Find Full Text PDF

Background: Height and body mass index (BMI) are associated with higher ovarian cancer risk in the general population, but whether such associations exist among BRCA1/2 mutation carriers is unknown.

Methods: We applied a Mendelian randomisation approach to examine height/BMI with ovarian cancer risk using the Consortium of Investigators for the Modifiers of BRCA1/2 (CIMBA) data set, comprising 14,676 BRCA1 and 7912 BRCA2 mutation carriers, with 2923 ovarian cancer cases. We created a height genetic score (height-GS) using 586 height-associated variants and a BMI genetic score (BMI-GS) using 93 BMI-associated variants.

View Article and Find Full Text PDF

The multifactorial likelihood analysis method has demonstrated utility for quantitative assessment of variant pathogenicity for multiple cancer syndrome genes. Independent data types currently incorporated in the model for assessing BRCA1 and BRCA2 variants include clinically calibrated prior probability of pathogenicity based on variant location and bioinformatic prediction of variant effect, co-segregation, family cancer history profile, co-occurrence with a pathogenic variant in the same gene, breast tumor pathology, and case-control information. Research and clinical data for multifactorial likelihood analysis were collated for 1,395 BRCA1/2 predominantly intronic and missense variants, enabling classification based on posterior probability of pathogenicity for 734 variants: 447 variants were classified as (likely) benign, and 94 as (likely) pathogenic; and 248 classifications were new or considerably altered relative to ClinVar submissions.

View Article and Find Full Text PDF

The Mediator is an evolutionarily conserved, multi-subunit complex that regulates multiple steps of transcription. Mediator activity is regulated by the reversible association of a four-subunit module comprising CDK8 or CDK19 kinases, together with cyclin C, MED12 or MED12L, and MED13 or MED13L. Mutations in MED12, MED13, and MED13L were previously identified in syndromic developmental disorders with overlapping phenotypes.

View Article and Find Full Text PDF

Background: Full-term pregnancy (FTP) is associated with a reduced breast cancer (BC) risk over time, but women are at increased BC risk in the immediate years following an FTP. No large prospective studies, however, have examined whether the number and timing of pregnancies are associated with BC risk for and mutation carriers.

Methods: Using weighted and time-varying Cox proportional hazards models, we investigated whether reproductive events are associated with BC risk for mutation carriers using a retrospective cohort (5707 and 3525 mutation carriers) and a prospective cohort (2276 and 1610 mutation carriers), separately for each cohort and the combined prospective and retrospective cohort.

View Article and Find Full Text PDF

Background: BRCA1/2 mutations confer high lifetime risk of breast cancer, although other factors may modify this risk. Whether height or body mass index (BMI) modifies breast cancer risk in BRCA1/2 mutation carriers remains unclear.

Methods: We used Mendelian randomization approaches to evaluate the association of height and BMI on breast cancer risk, using data from the Consortium of Investigators of Modifiers of BRCA1/2 with 14 676 BRCA1 and 7912 BRCA2 mutation carriers, including 11 451 cases of breast cancer.

View Article and Find Full Text PDF

Multiple primary tumors (MPTs) affect a substantial proportion of cancer survivors and can result from various causes, including inherited predisposition. Currently, germline genetic testing of MPT-affected individuals for variants in cancer-predisposition genes (CPGs) is mostly targeted by tumor type. We ascertained pre-assessed MPT individuals (with at least two primary tumors by age 60 years or at least three by 70 years) from genetics centers and performed whole-genome sequencing (WGS) on 460 individuals from 440 families.

View Article and Find Full Text PDF

Purpose: BRCA1/BRCA2 predictive test negatives are proven noncarriers of a BRCA1/BRCA2 mutation that is carried by their relatives. The risk of developing breast cancer (BC) or epithelial ovarian cancer (EOC) in these women is uncertain. The study aimed to estimate risks of invasive BC and EOC in a large cohort of BRCA1/BRCA2 predictive test negatives.

View Article and Find Full Text PDF

The prevalence and spectrum of germline mutations in BRCA1 and BRCA2 have been reported in single populations, with the majority of reports focused on White in Europe and North America. The Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) has assembled data on 18,435 families with BRCA1 mutations and 11,351 families with BRCA2 mutations ascertained from 69 centers in 49 countries on six continents. This study comprehensively describes the characteristics of the 1,650 unique BRCA1 and 1,731 unique BRCA2 deleterious (disease-associated) mutations identified in the CIMBA database.

View Article and Find Full Text PDF

Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,414 with breast cancer), all of European origin. We identified independent associations at P < 5 × 10 with ten variants at nine new loci.

View Article and Find Full Text PDF

Importance: The clinical management of BRCA1 and BRCA2 mutation carriers requires accurate, prospective cancer risk estimates.

Objectives: To estimate age-specific risks of breast, ovarian, and contralateral breast cancer for mutation carriers and to evaluate risk modification by family cancer history and mutation location.

Design, Setting, And Participants: Prospective cohort study of 6036 BRCA1 and 3820 BRCA2 female carriers (5046 unaffected and 4810 with breast or ovarian cancer or both at baseline) recruited in 1997-2011 through the International BRCA1/2 Carrier Cohort Study, the Breast Cancer Family Registry and the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer, with ascertainment through family clinics (94%) and population-based studies (6%).

View Article and Find Full Text PDF

Purpose BRCA1/2 mutations increase the risk of breast and prostate cancer in men. Common genetic variants modify cancer risks for female carriers of BRCA1/2 mutations. We investigated-for the first time to our knowledge-associations of common genetic variants with breast and prostate cancer risks for male carriers of BRCA1/ 2 mutations and implications for cancer risk prediction.

View Article and Find Full Text PDF