Prophylactic oophorectomy reduces breast cancer penetrance during prospective, long-term follow-up of BRCA1 mutation carriers.
ABSTRACT Breast cancer penetrance estimates in BRCA1 mutation carriers have varied from 40% to 85%; this heterogeneity has been attributed to variations in risk among different study populations. No study has taken oophorectomy status into account in estimating penetrance. Because prophylactic oophorectomy reduces breast cancer risk by approximately 50%, we hypothesized that population differences in oophorectomy prevalence might significantly influence breast cancer penetrance estimates.
Females from multiple-case breast/ovarian cancer families that segregate deleterious BRCA1 mutations were observed prospectively for breast cancer incidence and oophorectomy.
Within this cohort, 33 cases of breast cancer developed in 98 women with deleterious BRCA1 mutations during follow-up, yielding an estimated cumulative lifetime breast cancer risk of 80%. This estimate increased to 94% when the study participants were censored at the time of oophorectomy. Six of the 33 mutation-positive women who underwent oophorectomy during follow-up developed breast cancer, compared with 27 of 65 mutation carriers with intact ovaries (hazard ratio = 0.38; 95% CI, 0.15 to 0.97). Estimates of absolute breast cancer risk demonstrated that the protective effect of oophorectomy was strongest among women who were premenopausal at the time of surgery. When surgical status was ignored, the strong protective effect of oophorectomy, coupled with the high prevalence of the procedure in these families, led to a significantly lower estimate of the breast cancer penetrance in BRCA1 mutation carriers.
Differing rates of oophorectomy likely represent an underappreciated basis for a portion of the heterogeneity in estimated breast cancer penetrance described in BRCA mutation carriers, particularly mutation carriers from extensively affected, multiple-case families.
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ABSTRACT: Despite evidence that kinesin family member 14 (KIF14) can serve as a prognostic biomarker in various solid tumors, how it contributes to tumorigenesis remains unclear. We observed that experimental decrease in KIF14 expression increases docetaxel chemosensitivity in estrogen receptor-negative/progesterone receptor-negative/human epidermal growth factor receptor 2-negative, "triple-negative" breast cancers (TNBC). To investigate the oncogenic role of KIF14, we used noncancerous human mammary epithelial cells and ectopically expressed KIF14 and found increased proliferative capacity, increased anchorage-independent grown in vitro, and increased resistance to docetaxel but not to doxorubicin, carboplatin, or gemcitabine. Seventeen benign breast biopsies of BRCA1 or BRCA2 mutation carriers showed increased KIF14 mRNA expression by fluorescence in situ hybridization compared to controls with no known mutations in BRCA1 or BRCA2, suggesting increased KIF14 expression as a biomarker of high-risk breast tissue. Evaluation of 34 cases of locally advanced TNBC showed that KIF14 expression significantly correlates with chemotherapy-resistant breast cancer. KIF14 knockdown also correlates with decreased AKT phosphorylation and activity. Live-cell imaging confirmed an insulin-induced temporal colocalization of KIF14 and AKT at the plasma membrane, suggesting a potential role of KIF14 in promoting activation of AKT. An experimental small-molecule inhibitor of KIF14 was then used to evaluate the potential anticancer benefits of downregulating KIF14 activity. Inhibition of KIF14 shows a chemosensitizing effect and correlates with decreasing activation of AKT. Together, these findings show an early and critical role for KIF14 in the tumorigenic potential of TNBC, and therapeutic targeting of KIF14 is feasible and effective for TNBC.Neoplasia (New York, N.Y.) 03/2014; 16(3):247-256.e2. DOI:10.1016/j.neo.2014.03.008 · 5.40 Impact Factor
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ABSTRACT: Women with germline mutations in the cancer susceptibility genes, BRCA1 or BRCA2, associated with Hereditary Breast/Ovarian Cancer syndrome, have up to an 85% lifetime risk of breast cancer and up to a 46% lifetime risk ovarian cancer. Similarly, women with mutations in the DNA mismatch repair genes, MLH1, MSH2 or MSH6, associated with the Lynch/Hereditary Non-Polyposis Colorectal Cancer (HNPCC) syndrome, have up to a 40-60% lifetime risk of both endometrial and colorectal cancer as well as a 9-12% lifetime risk of ovarian cancer. Genetic risk assessment enables physicians to provide individualized evaluation of the likelihood of having one of these gynecologic cancer predisposition syndromes, as well the opportunity to provide tailored screening and prevention strategies such as surveillance, chemoprevention, and prophylactic surgery that may reduce the morbidity and mortality associated with these syndromes. Hereditary cancer risk assessment is a process that includes assessment of risk, education and counseling conducted by a provider with expertise in cancer genetics, and may include genetic testing after appropriate consent is obtained. This commentary provides guidance on identification of patients who may benefit from hereditary cancer risk assessment for Hereditary Breast/Ovarian Cancer and the Lynch/Hereditary Non-Polyposis Colorectal Cancer syndrome.Gynecologic Oncology 12/2007; 107(2):159-62. DOI:10.1016/j.ygyno.2007.09.031 · 3.69 Impact Factor
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ABSTRACT: The CEGRM was initially conceived as a simple, concise, visual representation of the social interaction domains of information, tangible services and emotional exchanges (Kenen, R., & Peters, J. (2001). J Genet Counsel, 10, 289-309). A blend of the genetic pedigree, genogram, and ecomap, the CEGRM was developed to facilitate contemporary genetic counseling goals. An exploratory pilot study of 20 subjects showed that it was feasible, comfortable and efficiently accomplished, and that the process was useful both for assessment and as an intervention with study participants (Peters, J. A., Kenen, R., Giusti, R., Loud, J., Weissman, N., & Greene, M. H. (2004). Am J Med Genet Part A, 130A, 258-264). Subsequently, we have extended the CEGRM to 150 women from hereditary breast/ovarian cancer (HBOC) families; three different investigators have successfully administered this tool. The preliminary findings from the exploratory study were confirmed in the larger sample. Engaging in the interactive, insight-promoting CEGRM process provides a novel tool for assessing the social context of genetic testing, and helping high-risk women better understand and integrate genetic information into their personal and family identities, health beliefs, and decisions.Journal of Genetic Counseling 12/2006; 15(6):477-89. DOI:10.1007/s10897-006-9042-7 · 1.75 Impact Factor