Ava Kwong

University of Ottawa, Ottawa, Ontario, Canada

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Publications (70)213.23 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Male breast cancer (bc) is a rare disease, and the availability of information on treatment outcomes is limited compared with that for female bc. The objective of the present study was to compare disease-free (dfs) and overall survival (os) for men compared with women having early-stage bc.
    Current oncology (Toronto, Ont.). 06/2014; 21(3):e400-7.
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    ABSTRACT: Western studies have shown that the uptake rates of surveillance and prophylaxis may vary among BRCA mutation carriers between ethnicities. The present study is the first to investigate the behavioural impact and subjective attitudes in Southern Chinese high-risk families who had undergone BRCA1 and BRCA2 genetic testing up to 2.5 years post-testing. Individuals who had such genetic testing and have consented to participate in the prospective database of Hong Kong Hereditary Breast Cancer Family Registry were recruited and surveyed by a face-to-face or telephone interview. Sociodemographic information, genetic test results, pre- and post-testing surveillance, medical regimes, and attitudes towards the choice of clinical management were obtained by interviews and retrieval of medical records using this prospective database. 69 females with breast cancer history were recruited into the study. Twenty-nine female carriers (15 BRCA1 mutated gene-carriers and 14 BRCA2 mutated gene-carriers) and 40 non-carriers of a BRCA 1/2 mutations were interviewed. The uptake rate of high risk breast screening i.e. clinical breast examination, mammography, and breast MRI is significantly higher among female carriers (48.3 %) after knowing genetic testing results than before (p < 0.01). A strong significant relationship between any increase or decrease of ovarian ultrasound screening (OS) and genetic status is found (p < .001), with more females did OS and with a higher frequency after knowing genetic testing results among both carriers (22.7 % → 86.4 %) and non-carriers (37.5 % → 50.0 %). Among carriers, very few opted for prophylactic surgeries. The present cohort might see prophylaxis as last resort and would use traditional Chinese medicine in cancer risk management.
    Familial Cancer 03/2014; · 1.94 Impact Factor
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    ABSTRACT: Stress adaptation has profound consequences for malignant progression and the response to therapy. BRCA1 is an important modulator of cellular stress, but our understanding of its mechanisms of action remains incomplete. Here we identify autophagy as an essential mechanism protecting BRCA1 deficient cancer cells from metabolic stress and allow their survival, which may underlie its significant cancer-promoting properties. We showed that targeted inhibition of endogenous BRCA1 using small interfering RNA caused significant autophagy in response to serum starvation and endoplasmic reticulum stress, whereas overexpression of BRCA1 did not, confirming that the effect was BRCA1 specific. We demonstrated that Beclin 1 was activated in BRCA1 deficient cells, suggesting involvement of a canonical pathway. Importantly, BRCA1 deficient cells were highly dependent on autophagy for survival, and rapidly underwent cell death upon disruption of autophagy. Notably, this dependence on protective autophagy extended to their tissue of origin, as ovarian surface epithelial cells from women testing positive for BRCA1 mutations, in contrast to those with no mutations, robustly induced autophagy to mitigate the stress and promote their survival. These findings highlight a novel role for BRCA1 in protective autophagy, which may make its essential contribution to tumorigenesis and prognosis.
    Cancer letters 12/2013; · 5.02 Impact Factor
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    ABSTRACT: Male breast cancer (MBC) is uncommon. As a result, there is limited availability of studies and reviews and even fewer reports from Asia. This is the largest population-based study to compare Chinese MBC patients with female patients during a 10-year period in Hong Kong, Southern China. A retrospective review of medical records of 132 male and 8,118 female breast cancer patients between year 1997 and 2006 in Hong Kong was performed. Each MBC patient was matched with three female breast cancer patients for further analysis. Different characteristics, overall, breast-cancer specific, and disease-free survivals (DFS) were compared. Mean age at diagnosis of male and female patients was 64.5 and 52.7 years respectively. Male patients showed lower histological grade, overall stage, smaller tumor size, and more positive sensitivity in hormone receptors. They were more likely to die of causes other than breast cancer. Matched analysis found that the 5-year overall survival (OS), breast-cancer-specific mortality, and DFS for male and female patients were 78.7, 90.5, 90.5, and 77.9, 86.4, and 81.4 % respectively. Male patients had poorer OS at early overall stage but better breast-cancer-specific mortality rates at any age (p < 0.01). Male patients had a significant risk of dying due to any cause in the presence of distant relapse and had less risk of dying when tumor was ER-positive and HER2-positive. Chinese male breast cancer patients tend to have poorer OS but better breast-cancer-specific survival compared with their female counterparts.
    Annals of Surgical Oncology 12/2013; · 4.12 Impact Factor
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    ABSTRACT: To assess the extent to which breast surgical consultations used shared decision making (SDM), identify factors associated with use of SDM, and assess if using SDM increases decision-making satisfaction. Two hundred and eighty-three video-recorded diagnostic-treatment decision consultations between breast surgeons and women with breast cancer were assessed using the Decision Analysis System for Oncology (DAS-O) coding system designed for assessing SDM behaviors. Women completed a questionnaire at pre-consultation, one-week post-consultation and one-month post-surgery. Patient outcomes included decision conflict, patient satisfaction with medical consultation, and decision regret. Overall, the level of SDM behaviors was low. The extent of SDM behavior within consultation was related to greater consultation duration (p<0.001), more than one treatment being offered (p<0.001), and fewer questions raised by patients/companions (p<0.05). While use of SDM consultation did not influence post-consultation decision conflict, it increased satisfaction with information given and explained, patients' feelings of trust and confidence in their surgeons, and reduced post-surgical decision regret. These breast surgical consultations mostly adopted informed treatment decision-making approaches. Using SDM improved patient consultation and decision satisfaction. The study findings highlight a need to reinforce the importance of SDM in consultations among breast surgeons.
    Patient Education and Counseling 11/2013; · 2.60 Impact Factor
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    ABSTRACT: The value for lymphocytic infiltration (LI) has been increasingly recognized for tumor assessment. In breast cancer, however, the overall significance of LI remains poorly defined, probably due to its heterogeneity. A large cohort of breast cancer was evaluated for the degree of LI and its association with traditional pathologic factors, biomarker expression, and cancer subtypes. The number of CD8 cytotoxic effector and FoxP3 regulatory T cell (Treg) was evaluated in those cases with high LI. High LI was associated with negative ER and PR but positive HER2 and EGFR expression (p < 0.001 for all). In ER-positive cancers, high LI was associated with poor prognostic features including higher grade, the presence of necrosis, and lymphovascular invasion (LVI) (p = 0.007 for LVI and <0.001 for the others). Conversely, LI correlated with smaller tumor size, a good prognostic feature (p = 0.046) in HER2+ ER-cancers. These observations suggested LI may show opposite prognostic values in different breast cancer subgroups. Interestingly, when the phenotype of LI in these subgroups was evaluated, a strong positive association with intratumoral accumulation of Treg was found in ER-positive cancers (p = 0.003, Rs = 0.319), while the opposite was observed in HER2+ ER-cancers (p < 0.001, Rs = -0.427). Also, in ER-positive cancers, positive associations between peri- and intra-tumoral distribution were found with both CD8 and Tregs (CD8: p < 0.001, Rs = 0.547; Treg: p = 0.001, Rs = 0.460). Nonetheless, in HER2+ ER-cancers, such strong association was found with CD8 (p < 0.001, Rs = 0.766) but not Tregs. The results may implicate a differential intratumoral migration of LI in different subtypes of breast cancer. In summary, the clinical value of LI in breast cancers could be subtype-dependent. In ER-positive cancers, high LI correlated with biologic parameters associated with poor prognosis, whereas in HER2 positive cancers, LI correlated with biologic parameters of favorable prognosis.
    Breast Cancer Research and Treatment 11/2013; · 4.47 Impact Factor
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    ABSTRACT: MicroRNAs (miRNAs) are small non-protein-coding RNAs that regulate expression of a wide variety of genes including those involved in cancer development. Here, we investigate the role of miR-143 in breast cancer. In this study, we showed that miR-143 was frequently downregulated in 80 % of breast carcinoma tissues compared to their adjacent noncancerous tissues. Ectopic expression of miR-143 inhibited proliferation and soft agar colony formation of breast cancer cells and also downregulated DNA methyltransferase 3A (DNMT3A) expression on both mRNA and protein levels. Restoration of miR-143 expression in breast cancer cells reduces PTEN hypermethylation and increases TNFRSF10C methylation. DNMT3A was demonstrated to be a direct target of miR-143 by luciferase reporter assay. Furthermore, miR-143 expression was observed to be inversely correlated with DNMT3A mRNA and protein expression in breast cancer tissues. Our findings suggest that miR-143 regulates DNMT3A in breast cancer cells. These findings elucidated a tumor-suppressive role of miR-143 in epigenetic aberration of breast cancer, providing a potential development of miRNA-based treatment for breast cancer.
    Tumor Biology 11/2013; · 2.52 Impact Factor
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    ABSTRACT: on behalf of the ENIGMA consortium BACKGROUND: Accurate evaluation of unclassified se-quence variants in cancer predisposition genes is essen-tial for clinical management and depends on a multi-factorial analysis of clinical, genetic, pathologic, and bioinformatic variables and assays of transcript length and abundance. The integrity of assay data in turn re-lies on appropriate assay design, interpretation, and reporting. METHODS: We conducted a multicenter investigation to compare mRNA splicing assay protocols used by mem-bers of the ENIGMA (Evidence-Based Network for the Interpretation of Germline Mutant Alleles) consor-tium. We compared similarities and differences in re-sults derived from analysis of a panel of breast cancer 1,
    Clinical Chemistry 11/2013; · 7.15 Impact Factor
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    ABSTRACT: This longitudinal study examined if the evolution of supportive care needs differed over the first year following the diagnosis of advanced breast cancer and examined factors differentiating these trajectories. Two hundred twenty-eight of 276 Chinese women with advanced breast cancer were assessed while they were awaiting or receiving initial chemotherapy, then again at 6 weeks, 3 months, 6 months, and 12 months post-baseline. Supportive care needs (SCNS-34-Ch), psychological distress (Hospital Anxiety and Depression scale), symptom distress (MSAS-Ch), and patient satisfaction (PSEQ-9) were assessed at baseline; supportive care needs were reassessed at each follow-up assessment. Latent growth mixture modeling explored if trajectories differed within each of four need domains: health system, information, and patient support (HSIPS); psychological; physical daily living (PDL); and sexuality needs. Logistic regression identified factors predicting trajectory patterns. Two distinct trajectories were identified for HSIPS and sexuality need domains and three distinct trajectories for psychological and physical daily living need domains. Most women showed stable low levels of HSIPS (78.9 %), psychological (82.4 %), PDL (83.7 %), and sexuality (97.4 %) supportive care needs. One in five and one in eight women showed high initial supportive care needs in HSIPS and psychological and PDL domains, respectively. With the exception of sexuality needs, trajectory patterns were predicted by physical symptom distress. Women in the high-decline group reported greater physical symptom distress. Most Chinese women with advanced breast cancer showed low stable supportive care needs. Physical symptom distress predicted high supportive care needs. Interventions should focus on optimizing symptom assessment and management.
    Supportive Care in Cancer 10/2013; · 2.09 Impact Factor
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    ABSTRACT: Several studies have suggested that viral oncogenesis is one of the etiologic factors of breast cancer, while others are provocative, however, their association remains controversial. The purpose of this study was to investigate whether the human papillomavirus (HPV) DNA is present in the blood and tissue samples of breast cancer patients in Hong Kong. A total of 102 patients with breast tumour tissues and adjacent normal tissues were available and recruited unselectively. Both DNA and RNA were extracted from those samples, and real-time quantitative PCR was performed to detect HPV-16, with 18 sequences targeting the E6 and L1 regions. Results showed that HPV DNA sequences were absent in all the blood and breast tissues. These data argue against the role of oncogenic HPV in the pathogenesis of breast cancer. Additional lines of evidence need to be obtained in order to assess the possibility of breast cancer prevention using HPV vaccines.
    ISRN Virology. 09/2013; 2013.
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    ABSTRACT: Data on the use of circulating microRNAs (miRNAs) as biomarkers of cardiovascular diseases are emerging. Little, however, is known on the expression profile of circulating of microRNAs in congenital heart malformations with a systemic right ventricle that is prone to functional impairment. We aimed to test the hypothesis that circulating miRNA profile is altered in patients late after atrial switch operation for complete transposition of the great arteries (TGA) and further explored possible relationships between alteration of circulating miRNAs and systemic ventricular contractility. Circulating miRNA expression profiling of serum samples from 5 patients and 5 healthy controls was performed. The results were validated in 26 patients and 20 controls using real-time quantitative reverse-transcription polymerase chain reaction for candidate miRNAs with fold changes >3 by expression profiling. Systemic ventricular myocardial acceleration during isovolumic contraction (IVA) was determined by colour tissue Doppler echocardiography. Compared with controls, patients had significantly lower systemic ventricular IVA (p = 0.002). Of the 23 upregulated miRNAs identified by profiling, 11 were validated to be increased in patients compared with controls: miR-16, miR-106a, miR-144*, miR-18a, miR-25, miR-451, miR-486-3p, miR-486-5p, miR-505*, let-7e and miR-93. Among the validated 11 miRNAs, miR-18a (r = -0.45, p = 0.002) and miR-486-5p (r = -0.35, p = 0.018) correlated negatively with systemic ventricular IVA for the whole cohort. A distinct serum miRNA expression signature exists in adults with complete TGA after atrial switch operation, with serum miR-18a and miR-486-5p being associated with systemic ventricular contractility.
    BMC Cardiovascular Disorders 09/2013; 13(1):73. · 1.46 Impact Factor
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    ABSTRACT: Diabetic mastopathy is an uncommon condition found in patients with long-standing diabetic mellitus (DM). Although benign in nature, it can sometimes not be distinguishable from breast carcinoma, and may lead to unnecessary anxiety or intervention. Clinicopathologic features of 10 patients were reviewed in detail. Only three of the 10 patients had type I DM. All patients had over a 10-year history of DM, and presented with unilateral, solitary, palpable breast mass, ranging in size from 1.5 to 5 cm. Radiologic and pathologic features of each patient were described. None of the patients in our series developed malignancy during the follow-up period. Diabetic mastopathy is a benign condition and not unique to type I DM. Surgeons should be aware of this distinct fibroinflammatory breast condition and its association with long-standing DM.
    The Breast Journal 09/2013; 19(5). · 1.83 Impact Factor
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    ABSTRACT: Anxiety and depression (distress) over the first year following the initial adjuvant therapy for advanced breast cancer (ABC) remain poorly documented in non-Caucasian populations. This study describes trajectories of distress and their determinants in Chinese women with ABC. Of the 228 Chinese women newly diagnosed with ABC recruited from six oncology units, 192 completed an interview before their first course of chemotherapy (baseline) and follow-up interviews at 1.5, 3, 6, and 12 months thereafter. At baseline, participants were assessed for supportive care needs, psychological distress, physical symptom distress, optimism, and cancer-related rumination. At follow-up, participants completed the measure of psychological distress. Latent growth mixture modeling was used to identify trajectory patterns of distress. Multinominal logistic regression was used to identify predictors of trajectory patterns adjusted for demographic and medical characteristics. Four distinct trajectories of anxiety and depression were identified. Most women showed low-stable levels of anxiety (68%) and depression (68%), but one in 11 women were chronically anxious (9%) and depressed (9%). Optimism, negative cancer-related rumination, and physical symptom distress predicted both anxiety and depression trajectories. Psychological needs predicted anxiety trajectories. Women in the low-stable distress group reported high optimism, low psychological supportive care needs, low physical symptom distress, and low negative cancer-related rumination. Most women with ABC did not experience psychological distress over 12 months following diagnosis of ABC. Preventive interventions should focus on women at risk of high persistent distress and reducing rumination, providing emotional support, and managing physical symptoms. Copyright © 2013 John Wiley & Sons, Ltd.
    Psycho-Oncology 08/2013; · 3.51 Impact Factor
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    ABSTRACT: PURPOSEBreast cancer (BC) decision aid (DA) randomized studies are limited to DA use in consultations among Western populations and for primary surgery. Their effectiveness beyond consultations, for reconstructive surgery and in other populations, has not been evaluated. We developed a DA administered after consultation for Chinese women deciding on BC surgery and, where relevant, immediate breast reconstruction, which was evaluated in this randomized controlled trial (RCT). PATIENTS AND METHODS Overall, 276 women considering BC surgery for early-stage BC were randomly assigned to receive a DA (take-home booklet) or the standard information booklet (control condition) after the initial consultation, wherein surgeons disclosed the diagnosis and discussed treatment options with patients. Using block random assignment by week, 138 women were assigned to the DA arm and 138 to the control arm. Participants completed interview-based questionnaires 1 week after consultation and then 1, 4, and 10 months after surgery. Primary outcome measures were decisional conflict, decision-making difficulties, BC knowledge 1 week after consultation, and decision regret 1 month after surgery. Secondary outcome measures were treatment decision, decision regret 4 and 10 months after surgery, and postsurgical anxiety and depression.ResultsThe DA group reported significantly lower decisional conflict scores 1 week after consultation (P = .016) compared with women in the control arm. Women receiving the DA had significantly lower decision regret scores 4 (P = .026) and 10 months (P = .014) after surgery and lower depression scores 10 months after surgery (P = .001). CONCLUSION This RCT demonstrated DAs may benefit Chinese patients in Hong Kong by reducing decisional conflict and subsequent regret and enhance clinical services for this population.
    Journal of Clinical Oncology 07/2013; · 18.04 Impact Factor
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    Breast Cancer Research 06/2013; 15(3). · 5.33 Impact Factor
  • Ava Kwong, Wai Wang Chau, K Kawase
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    ABSTRACT: PURPOSE: We evaluated the attitudes of female and male surgeons in Hong Kong to work, personal life, and work-life balance, through a questionnaire survey. METHODS: We sent an online questionnaire survey designed by a female Japanese surgeon to 142 female surgeons practicing in Hong Kong, while its customized version was sent to 953 of their male counterparts. RESULTS: "Home life" and "Work" were the first and second priorities for both the women and the men. More of the female surgeons reported that they could not find enough time to participate in community activities (p = 0.038) or rest (p = 0.024). Both reported moderate satisfaction at work (p = 0.114) and in their life outside work (p = 0.346), as well as equality at home (p = 0.548) and at work (p = 0.177). Of the men, 89 % agreed with the necessity for granting paternity leave and reported that they would like to work part-time during the child-rearing years (p = 0.013). CONCLUSIONS: The number of female surgeons involved in key roles is increasing in parallel with the increasing number of female medical students. The introduction of paternity leave for male surgeons is an important concern. The issues of work-life balance may need to be addressed to attract more talent into an important specialty in Hong Kong and this is likely to apply to other parts of Asia as well.
    Surgery Today 04/2013; · 0.96 Impact Factor
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    ABSTRACT: BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10(-8), HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10(-8), HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4×10(-8), HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific association. The 17q21.31 locus was also associated with ovarian cancer risk in 8,211 BRCA2 carriers (P = 2×10(-4)). These loci may lead to an improved understanding of the etiology of breast and ovarian tumors in BRCA1 carriers. Based on the joint distribution of the known BRCA1 breast cancer risk-modifying loci, we estimated that the breast cancer lifetime risks for the 5% of BRCA1 carriers at lowest risk are 28%-50% compared to 81%-100% for the 5% at highest risk. Similarly, based on the known ovarian cancer risk-modifying loci, the 5% of BRCA1 carriers at lowest risk have an estimated lifetime risk of developing ovarian cancer of 28% or lower, whereas the 5% at highest risk will have a risk of 63% or higher. Such differences in risk may have important implications for risk prediction and clinical management for BRCA1 carriers.
    PLoS Genetics 03/2013; 9(3):e1003212. · 8.52 Impact Factor
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    ABSTRACT: The prevalence and penetrance of BRCA1 and BRCA2 (BRCA1/2) mutations may differ between Asians and whites. We investigated BRCA1/2 mutations and cancer risk factors in a clinic-based sample. BRCA1/2 mutation carriers were enrolled from cancer genetics clinics in Hong Kong and California according to standardized entry criteria. We compared BRCA mutation position, cancer history, hormonal and reproductive exposures. We analyzed DNA samples for single-nucleotide polymorphisms reported to modify breast cancer risk. We performed logistic regression to identify independent predictors of breast cancer. Fifty Asian women and forty-nine white American women were enrolled. BRCA1 mutations were more common among whites (67 vs. 42 %, p = 0.02), and BRCA2 mutations among Asians (58 vs. 37 %, p = 0.04). More Asians had breast cancer (76 vs. 53 %, p = 0.03); more whites had relatives with breast cancer (86 vs. 50 %, p = 0.0003). More whites than Asians had breastfed (71 vs. 42 %, p = 0.005), had high BMI (median 24.3 vs. 21.2, p = 0.04), consumed alcohol (2 drinks/week vs. 0, p < 0.001), and had oophorectomy (61 vs. 34 %, p = 0.01). Asians had a higher frequency of risk-associated alleles in MAP3K1 (88 vs. 59 %, p = 0.005) and TOX3/TNRC9 (88 vs. 55 %, p = 0.0002). On logistic regression, MAP3K1 was associated with increased breast cancer risk for BRCA2, but not BRCA1 mutation carriers; breast density was associated with increased risk among Asians but not whites. We found significant differences in breast cancer risk factors between Asian and white BRCA1/2 mutation carriers. Further investigation of racial differences in BRCA1/2 mutation epidemiology could inform targeted cancer risk-reduction strategies.
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    ABSTRACT: We previously showed microRNAs (miRNAs) in plasma are potential biomarkers for colorectal cancer detection. Here, we aimed to develop specific blood-based miRNA assay for breast cancer detection. TaqMan-based miRNA profiling was performed in tumor, adjacent non-tumor, corresponding plasma from breast cancer patients, and plasma from matched healthy controls. All putative markers identified were verified in a training set of breast cancer patients. Selected markers were validated in a case-control cohort of 170 breast cancer patients, 100 controls, and 95 other types of cancers and then blindly validated in an independent set of 70 breast cancer patients and 50 healthy controls. Profiling results showed 8 miRNAs were concordantly up-regulated and 1 miRNA was concordantly down-regulated in both plasma and tumor tissue of breast cancer patients. Of the 8 up-regulated miRNAs, only 3 were significantly elevated (p<0.0001) before surgery and reduced after surgery in the training set. Results from the validation cohort showed that a combination of miR-145 and miR-451 was the best biomarker (p<0.0001) in discriminating breast cancer from healthy controls and all other types of cancers. In the blind validation, these plasma markers yielded Receiver Operating Characteristic (ROC) curve area of 0.931. The positive predictive value was 88% and the negative predictive value was 92%. Altered levels of these miRNAs in plasma have been detected not only in advanced stages but also early stages of tumors. The positive predictive value for ductal carcinoma in situ (DCIS) cases was 96%. These results suggested that these circulating miRNAs could be a potential specific biomarker for breast cancer screening.
    PLoS ONE 01/2013; 8(1):e53141. · 3.53 Impact Factor
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    ABSTRACT: BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7x10(-8), HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4x10(-8), HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4x10(-8), HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific association. The 17q21.31 locus was also associated with ovarian cancer risk in 8,211 BRCA2 carriers (P = 2x10(-4)). These loci may lead to an improved understanding of the etiology of breast and ovarian tumors in BRCA1 carriers. Based on the joint distribution of the known BRCA1 breast cancer risk-modifying loci, we estimated that the breast cancer lifetime risks for the 5% of BRCA1 carriers at lowest risk are 28%-50% compared to 81%-100% for the 5% at highest risk. Similarly, based on the known ovarian cancer risk-modifying loci, the 5% of BRCA1 carriers at lowest risk have an estimated lifetime risk of developing ovarian cancer of 28% or lower, whereas the 5% at highest risk will have a risk of 63% or higher. Such differences in risk may have important implications for risk prediction and clinical management for BRCA1 carriers.
    01/2013: pages e1003212;

Publication Stats

404 Citations
213.23 Total Impact Points

Institutions

  • 2014
    • University of Ottawa
      Ottawa, Ontario, Canada
  • 2013
    • Hong Kong SAR Government
      Hong Kong, Hong Kong
  • 2011–2013
    • Kwong Wah Hospital
      Hong Kong, Hong Kong
  • 2009–2013
    • The University of Hong Kong
      • • Department of Surgery
      • • School of Public Health
      Hong Kong, Hong Kong
  • 2008–2013
    • Hong Kong Sanatorium & Hospital
      Hong Kong, Hong Kong
  • 2012
    • Mayo Clinic - Rochester
      Rochester, Minnesota, United States
  • 2007–2012
    • Queen Mary Hospital
      Hong Kong, Hong Kong
  • 2007–2008
    • Stanford Medicine
      • Department of Surgery
      Stanford, California, United States
    • Stanford University
      • Department of Surgery
      Stanford, CA, United States