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.
Women undergoing premenopausal oophorectomy for a variety of reasons, including to reduce ovarian or breast cancer risk were evaluated for accelerated bone loss.
The Gynecologic Oncology Group ...(GOG)-0215 randomized phase-II trial of zoledronic acid was initiated to determine if postoophorectomy bisphosphonate therapy could prevent this bone loss. The study was closed after slow accrual prevented evaluation of the primary study endpoint. We analyzed changes in bone mineral density (BMD) among the 80 women randomized to the observation arm of this study, as measured 3, 9, and 18 months postenrollment.
The mean change in BMD from baseline to 18 months was -0.09 (95% CI, -0.12 to -0.07), -0.05 (95% CI, -0.07 to -0.03), and -0.06 (95% CI, -0.07 to -0.05) g/cm across the lumbar spine, right hip, and left hip, respectively. This represents a BMD decrease of -8.5% for the lumbar spine and -5.7% for both the right and left hips from baseline to 18 months' observation.
These results demonstrate that premenopausal women undergoing oophorectomy clearly experience bone loss, an adverse effect of oophorectomy, which requires attention and active management. BMD should be monitored postoophorectomy, and treated per standard practice guidelines. Future studies will be required to determine if early treatment can mitigate fracture risk, and to test promising therapeutic interventions and novel prevention strategies, such as increased physical activity or alternative medications, in randomized trials.
This study aimed to compare histological features of familial and sporadic testicular germ cell tumors (TGCTs) and surrounding parenchyma, since discriminating features might be etiologically ...relevant and clinically useful. The study of parenchyma was prompted by reports claiming a higher prevalence of testicular microlithiasis in familial cases. Histological features of TGCTs and surrounding parenchyma of 296 sporadic and 305 familial cases were compared. For each case, one representative hematoxylin and eosin-stained slide was available. Slides were independently scored by two expert pathologists using a semi-quantitative data abstract. Discrepancies were resolved by consensus. A logistic regression model was used to assess the ability to discriminate between sporadic and familial GCT. The histological composition of a tumor, amount of lymphocytic infiltration, amount of germ cell neoplasia in situ (GCNIS), and presence of testicular microlithiasis (TM) did not discriminate between sporadic and familial GCT (area under the curve 0.56, 95%CI 0.51-0.61). Novel observations included increasing lymphocytic infiltration and decreasing GCNIS and TM with increasing age at diagnosis. The presence of tubules with infiltrating lymphocytes was mainly associated with pure seminomas and nonseminomas with a seminoma component. Among seminomas, tubules with infiltrating lymphocytes decreased with increasing age. No discernable differences between sporadic and familial TGCTs were found. The age-related changes in the tumors and surrounding parenchyma in these groups combined are consistent with a host response building up over time predominantly affecting seminomas, the seminoma-component of nonseminomas and GCNIS. TM may gradually dissolve with age. Our hypothesis that histological differences between sporadic and familial TGCT might identify genetically distinct disease subsets was not supported.
Given the importance of the dissemination of accurate family history to assess disease risk, we characterized the gatherers, disseminators, and blockers of health information within families at high ...genetic risk of cancer.
A total of 5466 personal network members of 183 female participants of the Breast Imaging Study from 124 families with known mutations in the BRCA1/2 genes (associated with high risk of breast, ovarian, and other types of cancer) were identified by using the Colored Eco-Genetic Relationship Map (CEGRM). Hierarchical nonlinear models were fitted to characterize information gatherers, disseminators, and blockers.
Gatherers of information were more often female (P<.001), parents (P<.001), and emotional support providers (P<.001). Disseminators were more likely female first- and second-degree relatives (both P<.001), family members in the older or same generation as the participant (P<.001), those with a cancer history (P<.001), and providers of emotional (P<.001) or tangible support (P<.001). Blockers tended to be spouses or partners (P<.001) and male, first-degree relatives (P<.001).
Our results provide insight into which family members may, within a family-based intervention, effectively gather family risk information, disseminate information, and encourage discussions regarding shared family risk.
Testicular germ cell tumors (TGCT) are the most frequent cancers among young men. There is a clear familial component to TGCT etiology, but no high-penetrance susceptibility gene has been identified. ...Epigenetic aberrations of the genome represent an alternative mechanism for cancer susceptibility; and, studies suggest that epigenetic changes that influence cancer risk can be inherited through the germline. Global DNA hypomethylation has been associated with the risk of cancers of the bladder and head/neck.
We performed a pilot study of global methylation at long interspersed nuclear elements-1 (LINE-1) in peripheral blood DNA isolated from 466 family members of 101 multiple-case testicular cancer families.
Investigating the correlation of LINE-1 methylation levels among parent-child pairs independent of affection status (n = 355) revealed a strong positive association only between mother-daughter (r = 0.48, P = <0.001) and father-daughter pairs (r = 0.31, P = 0.02), suggesting gender-specific inheritance of methylation. Incorporating cancer status, we observed a strong correlation in LINE-1 methylation levels only among affected father-affected son pairs (r = 0.49, P = 0.03). There was a marginally significant inverse association between lower LINE-1 methylation levels and increased TGCT risk, compared with healthy male relatives (P = 0.049).
Our data suggest that heritability of LINE-1 methylation may be gender-specific. Further, the strong correlation between LINE-1 methylation levels among affected father-affected son pairs suggests that transgenerational inheritance of an epigenetic event may be associated with disease risk. Larger studies are needed to clarify these preliminary observations.
Young women who carry BRCA1/2 mutations face difficult decisions in managing their hereditary breast/ovarian cancer risk. Through this National Cancer Institute study, we sought to understand the ...process by which some young women choose risk-reducing bilateral mastectomy (RRBM) instead of alternative risk-management options. Data indicate that electing to undergo RRBM, although difficult, is experienced as a way to sidestep potentially devastating outcomes, such as stressful and costly high-risk screening, chemotherapy or radiation, or putting loved ones through the challenges of a cancer diagnosis. The decision to pursue RRBM is often the product of screening fatigue, encouragement from loved ones, and/or a sense of urgency to put one’s high-risk period behind one. By understanding how young carriers make decisions about surgical risk reduction, providers can better guide, counsel, and support patients in the important tasks surrounding this life-changing medical decision, thereby helping to increase the duration and quality of their lives.
Eligibility guidelines for genetic testing may be revisited, given technological advances, plummeting costs, and proposals for population mutation screening. A key property of eligibility criteria is ...the tradeoff between the number of mutation carriers identified versus population members tested. We assess the fractions of mutation carriers identified, versus women undergoing mutation testing, for
founder mutation screening in U.S. Ashkenazi-Jewish women.
carrier probabilities, based on personal/family history, were calculated using the risk-prediction tool BRCAPRO for 4,589 volunteers (102 mutation carriers) in the population-based Washington Ashkenazi Study. For each carrier-probability threshold between 0% and 10%, we compared the percentage of founder mutations detected versus the percentage of women requiring mutation testing. PCR mutation testing was conducted at the NIH for the 3 Ashkenazi-Jewish founder mutations (5382insC and 185delAG in
, and 6174delT in
).
Identifying 90% of
founder mutations required testing the 60% of Ashkenazi-Jewish women with carrier probabilities exceeding 0.56%, potentially avoiding mutation testing for approximately 0.7 to 1.1 million U.S. Ashkenazi-Jewish women. Alternatively, testing the 44% whose carrier probability exceeded 0.78% identified 80% of mutation carriers, increasing to 89% of mutation carriers when accounting for cascade testing triggered after mutation-positive daughters were identified by screening. We present data on all carrier-probability thresholds, e.g., a 5% threshold identified 46% of mutation carriers while testing 10% of women.
Different carrier-probability thresholds offered diverse tradeoffs between numbers of identified mutation carriers versus women tested. Low carrier-probability thresholds identified 90% of
founder mutation carriers, without testing approximately 1 million U.S. Ashkenazi-Jewish women with lowest carrier probabilities.
In general, this risk-based framework could provide useful new options to consider during eligibility-criteria development for population mutation screening.
Myotonic muscular dystrophy (MMD) is an autosomal-dominant multisystem neuromuscular disorder characterized by unstable nucleotide repeat expansions. Case reports have suggested that MMD patients may ...be at increased risk of malignancy, putative risks that have never been quantified.
To quantitatively evaluate cancer risk in patients with MMD, overall and by sex and age.
We identified 1658 patients with an MMD discharge diagnosis in the Swedish Hospital Discharge Register or Danish National Patient Registry between 1977 and 2008. We linked these patients to their corresponding cancer registry. Patients were followed up from date of first MMD-related inpatient or outpatient contact to first cancer diagnosis, death, emigration, or completion of cancer registration.
Risks of all cancers combined and by anatomic site, stratified by sex and age.
One hundred four patients with an inpatient or outpatient discharge diagnosis of MMD developed cancer during postdischarge follow-up. This corresponds to an observed cancer rate of 73.4 per 10,000 person-years in MMD vs an expected rate of 36.9 per 10,000 person-years in the general Swedish and Danish populations combined (standardized incidence ratio SIR, 2.0; 95% CI, 1.6-2.4). Specifically, we observed significant excess risks of cancers of the endometrium (n = 11; observed rate, 16.1/10,000 person-years; SIR, 7.6; 95% CI, 4.0-13.2), brain (n = 7; observed rate, 4.9/10,000 person-years; SIR, 5.3; 95% CI, 2.3-10.4), ovary (n = 7; observed rate, 10.3/10,000 person-years; SIR, 5.2; 95% CI, 2.3-10.2), and colon (n = 10; observed rate, 7.1/10,000 person-years; SIR, 2.9; 95% CI, 1.5-5.1). Cancer risks were similar in women and men after excluding genital organ tumors (SIR, 1.9; 95% CI, 1.4-2.5, vs SIR, 1.8; 95% CI, 1.3-2.5, respectively; P = .81 for heterogeneity; observed rates, 64.5 and 47.7 per 10,000 person-years in women and men, respectively). The same pattern of cancer excess was observed first in the Swedish and then in the Danish cohorts, which were studied sequentially and initially analyzed independently.
Patients with MMD identified from the Swedish and Danish patient registries were at increased risk of cancer both overall and for selected anatomic sites.
Knowledge of family cancer history is essential for estimating an individual's cancer risk and making clinical recommendations regarding screening and referral to a specialty cancer genetics clinic. ...However, it is not clear if reported family cancer history is sufficiently accurate for this purpose.
In the population-based 2001 Connecticut Family Health Study, 1019 participants reported on 20 578 first-degree relatives (FDR) and second-degree relatives (SDR). Of those, 2605 relatives were sampled for confirmation of cancer reports on breast, colorectal, prostate, and lung cancer. Confirmation sources included state cancer registries, Medicare databases, the National Death Index, death certificates, and health-care facility records. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for reports on lung, colorectal, breast, and prostate cancer and after stratification by sex, age, education, and degree of relatedness and used to estimate report accuracy. Pairwise t tests were used to evaluate differences between the two strata in each stratified analysis. All statistical tests were two-sided.
Overall, sensitivity and positive predictive value were low to moderate and varied by cancer type: 60.2% and 40.0%, respectively, for lung cancer reports, 27.3% and 53.5% for colorectal cancer reports, 61.1% and 61.3% for breast cancer reports, and 32.0% and 53.4% for prostate cancer reports. Specificity and negative predictive value were more than 95% for all four cancer types. Cancer history reports on FDR were more accurate than reports on SDR, with reports on FDR having statistically significantly higher sensitivity for prostate cancer than reports on SDR (58.9% vs 21.5%, P = .002) and higher positive predictive value for lung (78.1% vs 31.7%, P < .001), colorectal (85.8% vs 43.5%, P = .004), and breast cancer (79.9% vs 53.6%, P = .02).
General population reports on family history for the four major adult cancers were not highly accurate. Efforts to improve accuracy are needed in primary care and other health-care settings in which family history is collected to ensure appropriate risk assessment and clinical care recommendations.
In this issue of the journal, Cramer and colleagues and Zhu and colleagues report carefully designed phase 3 assessments of candidate ovarian cancer screening biomarkers. The main conclusion is that ...CA-125 remains the "best of a bad lot"; the new candidates have fallen short of expectations. We review factors impeding the development of an effective ovarian cancer screening strategy, highlight the requirements related to validating proposed screening biomarkers, and emphasize the risks from premature clinical applications of unvalidated tests, all underscoring the need for new research strategies.
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