Clinical options for women at high risk for breast cancer

Clinicogenetic care of women of BRCA mutation carrier women: prevention, diagnosis and therapy

Predictive genetics opens a considerable perspective in the diagnostics as well as the treatment of breast and ovarian cancer. Current recommendations and guidelines for the management of BRCA 1 and BRCA 2 mutation carriers are not based on controlled randomized trials, but on expert opinions. The existing options of prevention, early diagnosis and treatment must be clearly interpreted to the patient. In the context of a dedicated genetic counseling the participation of all involved professionals (geneticist, oncologist, surgeon, gynecologist) is required. The decision-making process concerning the possibilities of prevention, diagnosis and treatment is always deeply influenced by the patient’s own experience with the cancer occurred in the family, as well as by her values and expectations of life. The focused multidisciplinary approach, with the application of results from prospective studies in cohorts of BRCA mutation carriers allow the concerned individuals to benefit from this kind of approach of medical treatment. Orv. Hetil., 2011, 152, 913–918.

Volume of mammographic density and risk of breast cancer

BACKGROUND

Assessing the volume of mammographic density might more accurately reflect the amount of breast volume at risk of malignant transformation and provide a stronger indication of risk of breast cancer than methods based on qualitative scores or dense breast area.

METHODS

We prospectively collected mammograms for women undergoing screening mammography. We determined the diagnosis of subsequent invasive or ductal carcinoma in situ for 275 cases, selected 825 controls matched for age, ethnicity, and mammography system, and assessed three measures of breast density: percent dense area, fibroglandular volume, and percent fibroglandular volume.

RESULTS

After adjustment for familial breast cancer history, body mass index, history of breast biopsy, and age at first live birth, the ORs for breast cancer risk in the highest versus lowest measurement quintiles were 2.5 (95% CI: 1.5-4.3) for percent dense area, 2.9 (95% CI: 1.7-4.9) for fibroglandular volume, and 4.1 (95% CI: 2.3-7.2) for percent fibroglandular volume. Net reclassification indexes for density measures plus risk factors versus risk factors alone were 9.6% (P = 0.07) for percent dense area, 21.1% (P = 0.0001) for fibroglandular volume, and 14.8% (P = 0.004) for percent fibroglandular volume. Fibroglandular volume improved the categorical risk classification of 1 in 5 women for both women with and without breast cancer.

CONCLUSION

Volumetric measures of breast density are more accurate predictors of breast cancer risk than risk factors alone and than percent dense area.

IMPACT

Risk models including dense fibroglandular volume may more accurately predict breast cancer risk than current risk models.

mRNA expression profiles show differential regulatory effects of microRNAs between estrogen receptor-positive and estrogen receptor-negative breast cancer

Most microRNAs have a stronger inhibitory effect in estrogen receptor-negative than in estrogen receptor-positive breast cancers

Background

Recent studies have shown that the regulatory effect of microRNAs can be investigated by examining expression changes of their target genes. Given this, it is useful to define an overall metric of regulatory effect for a specific microRNA and see how this changes across different conditions.

Results

Here, we define a regulatory effect score (RE-score) to measure the inhibitory effect of a microRNA in a sample, essentially the average difference in expression of its targets versus non-targets. Then we compare the RE-scores of various microRNAs between two breast cancer subtypes: estrogen receptor positive (ER⁺) and negative (ER^-). We applied this approach to five microarray breast cancer datasets and found that the expression of target genes of most microRNAs was more repressed in ER^- than ER⁺; that is, microRNAs appear to have higher RE-scores in ER^- breast cancer. These results are robust to the microRNA target prediction method. To interpret these findings, we analyzed the level of microRNA expression in previous studies and found that higher microRNA expression was not always accompanied by higher inhibitory effects. However, several key microRNA processing genes, especially Ago2 and Dicer, were differentially expressed between ER^- and ER⁺ breast cancer, which may explain the different regulatory effects of microRNAs in these two breast cancer subtypes.

Conclusions

The RE-score is a promising indicator to measure microRNAs' inhibitory effects. Most microRNAs exhibit higher RE-scores in ER^- than in ER⁺ samples, suggesting that they have stronger inhibitory effects in ER^- breast cancers.

Characterization of the pathogenic mechanism of a novel BRCA2 variant in a Chinese family

INTRODUCTION

Germline mutations of BRCA1 and BRCA2 account for the majority of hereditary breast cancers, many of which are classified as variants of unknown significance (VUS). We report the identification of a novel BRCA2 variant (c.7806-9T > G) in a Chinese family with multiple breast cancers and document it as a pathogenic mutation.

METHODS

The proband in this family was diagnosed with breast cancer at age 50 with a strong family history of breast cancer. DNA and RNA were extracted from the blood of the proband and her family, and was used for BRCA gene mutation/deletion screening and RNA splicing analysis.

RESULTS

BRCA2 c.7806-9T > G was identified in the proband, which was suggestive of a variant. This change was also found in two sisters of the proband with a history of breast cancer, as well as from the proband's maternal gastric cancer. The only sibling free of breast cancer did not carry the BRCA2 variant, thus demonstrating that the mutation segregates with the clinical phenotype in this family. RNA analysis on the proband blood sample revealed three aberrant splicing variants: c.7806_7874del, c.7806_7976del, and c.7806-8_7806-1ins. The latter causes a frameshift and creates a truncated protein, whilst the other two splicing variants resulted in shorter forms of the protein.

CONCLUSIONS

The identified BRCA2 c.7806-9T > G [Genbank: DQ889340] was found to be pathogenic, based on aberrant splicing events resulting in the formation of truncated protein products. Thus, better understanding and classification of BRCA variants as neutral or disease causing has important implications for genetic counseling so that appropriate management can be given.

Assessing breast tissue density by transillumination breast spectroscopy (TIBS): an intermediate indicator of cancer risk

Risk assessment by parenchymal density pattern, a strong physical indicator of future breast cancer risk, is available with the onset of mammographic screening programmes. However, due to the use of ionizing radiation, mammography is not recommended for use in younger women, thereby rendering risk assessment unattainable at an earlier age. Visible and near infrared light was used on 292 women with radiologically normal mammograms to determine whether transillumination breast spectroscopy (TIBS) can identify women with a high parenchymal density pattern as an intermediate indicator of breast cancer risk. Principal component analysis (PCA) was used to reduce the spectral data and generate density scores for each woman. To assess the accuracy of TIBS, logistic regression was used to calculate crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) for each score. Receiver operator characteristic (ROC) curves and area under the curve (AUC) were also calculated for the crude and adjusted logistic models. Optical information relating to tissue chromophores, such as water, lipid and haemoglobin content, was sufficient to identify women with high parenchymal density. The resulting AUC for the final and most parsimonious multivariate logistic model was 0.922 (95% CI 0.878-0.967). TIBS provides information correlating to high parenchymal density and is a promising tool for risk assessment, particularly for younger women.

Breast cancer screening in women at increased risk according to different family histories: an update of the Modena Study Group experience

BACKGROUND

Breast cancer (BC) detection in women with a genetic susceptibility or strong family history is considered mandatory compared with BC screening in the general population. However, screening modalities depend on the level of risk. Here we present an update of our screening programs based on risk classification.

METHODS

We defined different risk categories and surveillance strategies to identify early BC in 1325 healthy women recruited by the Modena Study Group for familial breast and ovarian cancer. Four BC risk categories included BRCA1/2 carriers, increased, intermediate, and slightly increased risk. Women who developed BC from January 1, 1994, through December 31, 2005 (N = 44) were compared with the number of expected cases matched for age and period. BRCA1/2 carriers were identified by mutational analysis. Other risk groups were defined by different levels of family history for breast or ovarian cancer (OC). The standardized incidence ratio (SIR) was used to evaluate the observed and expected ratio among groups. All statistical tests were two-sided.

RESULTS

After a median follow-up of 55 months, there was a statistically significant difference between observed and expected incidence [SIR = 4.9; 95% confidence interval (CI) = 1.6 to 7.6; p < 0.001]. The incidence observed among BRCA carriers (SIR = 20.3; 95% CI = 3.1 to 83.9; P < 0.001), women at increased (SIR = 4.5; 95% CI = 1.5 to 8.3; P < 0.001) or intermediate risk (SIR = 7.0, 95% CI = 2.0 to 17.1; P = 0.0018) was higher than expected, while the difference between observed and expected among women at slightly increased risk was not statistically significant (SIR = 2.4, 95% CI = 0.9 to 8.3; P = .74).

CONCLUSION

The rate of cancers detected in women at high risk according to BRCA status or strong family history, as defined according to our operational criteria, was significantly higher than expected in an age-matched general population. However, we failed to identify a greater incidence of BC in the slightly increased risk group. These results support the effectiveness of the proposed program to identify and monitor individuals at high risk, whereas prospective trials are needed for women belonging to families with sporadic BC or OC.

Acceptance of preventive surgeries by Israeli women who had undergone BRCA testing

Using a specially constructed questionnaire, the effect of BRCA test results for the Jewish founder mutations and genetic counseling on women's attitudes towards and acceptance of preventive surgeries was evaluated. The subjects consisted of 99 women 43% of whom were found to be carriers as opposed to 57%--non-carriers. After learning of their genetic status, 94% of the carriers and 28% of the non-carriers declared having positively considered the option of preventive oophorectomy. However, only about 25% of the carriers and 4.5% of the non-carriers had positively considered the option of preventive mastectomy. In practice, 78% of the carriers and 18% of the non-carriers who proved to be eligible for these procedures underwent preventive oophorectomy compared with 19% of carriers and 1.8% of non-carriers who underwent preventive mastectomy. Almost all carriers, as well as a majority of the non-carriers, who finally opted for the preventive surgeries did so after learning the result of their genetic test. The different attitudes toward the two surgeries were found to be based on varied beliefs regarding the two procedures. Preventive oophorectomy was perceived as being more acceptable to women than preventive mastectomy both from an attitudinal as well as practical aspect. These differences may be the result of cultural factors, of women's trust in the ability of screening tests to prevent morbidity and/or mortality, of the effect of the surgeries on body image and of different counseling protocols.

A multicenter study of supportive-expressive group therapy for women with BRCA1/BRCA2 mutations

BACKGROUND

Women with a BRCA1/BRCA2 mutation experience significant challenges. These include decision-making regarding surgical options and notification to offspring and family, along with a sense of isolation, which may lead to psychological and emotional distress. The current study developed, standardized, and conducted preliminary testing of a supportive-expressive group therapy intervention designed to address these challenges.

METHODS

Seventy women with a BRCA1/BRCA2 mutation recruited from familial cancer risk clinics participated in 12 sessions of supportive-expressive group therapy that lasted 6 months. Before and after measures of psychosocial functioning, knowledge, and surveillance/surgery activities were completed.

RESULTS

Sixty-seven women completed the intervention. Significant improvements were observed in psychosocial functioning: cancer worries (P = 0.005), anxiety (P = 0.033), and depression (P = 0.015). Knowledge level and surveillance levels were high at baseline and there were no significant changes postintervention. A significant number of women made decisions concerning prophylactic surgery (oophorectomy/mastectomy) during and after the intervention.

CONCLUSIONS

The feasibility of a supportive-expressive group for BRCA1/BRCA2 mutation carriers was demonstrated. Findings from the study are consistent with an effective intervention. However, further research is required using a randomized controlled study design.

Reoperations after prophylactic mastectomy with or without implant reconstruction

BACKGROUND

The authors characterized the unanticipated reoperations after prophylactic mastectomy, with or without implant reconstruction.

METHODS

The surgical cohort was comprised of 1417 women with a family history of breast carcinoma. The women received a prophylactic mastectomy with (bilateral, n = 593; contralateral, n = 506) or without reconstruction (n = 318) at the Mayo Clinic (Rochester, MN) between 1960 and 1993. Reoperations and indications for reoperation were compiled from medical records and a patient survey.

RESULTS

Three hundred eighteen women received a bilateral (n = 39) or contralateral (n = 279) prophylactic mastectomy without reconstruction. With a median follow-up of 15 years, 18 women (6%) required reoperation. Most of these reoperations occurred within the first year after prophylactic mastectomy. Five hundred ninety-three women had reconstruction with implants following bilateral prophylactic mastectomy. Approximately one-half of the women (52%) required at least 1 unanticipated reoperation during a median follow-up of 14 years. Approximately 39% of all reoperations occurred within 1 year of breast reconstruction and 69% within 5 years. Implant-related issues were the most common cause for reoperation. Some women with breast carcinoma elected to receive contralateral prophylactic mastectomy with therapeutic mastectomy for the affected breast. Five hundred six women received reconstruction with implants. During a median follow-up of 8.8 years, 189 women (37%) required unanticipated reoperation. The most common indication was implant-related issues. The time course of reoperations was similar to that for women in the bilateral group.

CONCLUSIONS

Surgical reoperations were fairly common among women who received prophylactic mastectomy with implant reconstruction. Most of the reoperations were implant related. Reoperations were fairly uncommon after prophylactic mastectomy without reconstruction.

Counseling the at risk patient in the BRCA1 and BRCA2 Era

The 5-year experience since the identification of the BRCA1 and BRCA2 genes has shown that genetic evaluation and testing can increase understanding of cancer risks for individuals with a personal or family history of early onset breast cancer and ovarian cancer. However, testing needs to be undertaken in a clinical setting where pretest counseling, including likelihood of identifying a mutation and risks and benefits of the process are provided. Identifying women who carry mutations in either BRCA1 or BRCA2 has implications for prevention, screening and treatment of these cancers.

Ductal lavage for detection of cellular atypia in women at high risk for breast cancer

BACKGROUND

Breast cancer originates in breast epithelium and is associated with progressive molecular and morphologic changes. Women with atypical breast ductal epithelial cells have an increased relative risk of breast cancer. In this study, ductal lavage, a new procedure for collecting ductal cells with a microcatheter, was compared with nipple aspiration with regard to safety, tolerability, and the ability to detect abnormal breast epithelial cells.

METHODS

Women at high risk for breast cancer who had nonsuspicious mammograms and clinical breast examinations underwent nipple aspiration followed by lavage of fluid-yielding ducts. All statistical tests were two-sided.

RESULTS

The 507 women enrolled included 291 (57%) with a history of breast cancer and 199 (39%) with a 5-year Gail risk for breast cancer of 1.7% or more. Nipple aspirate fluid (NAF) samples were evaluated cytologically for 417 women, and ductal lavage samples were evaluated for 383 women. Adequate samples for diagnosis were collected from 111 (27%) and 299 (78%) women, respectively. A median of 13,500 epithelial cells per duct (range, 43-492,000 cells) was collected by ductal lavage compared with a median of 120 epithelial cells per breast (range, 10-74,300) collected by nipple aspiration. For ductal lavage, 92 (24%) subjects had abnormal cells that were mildly (17%) or markedly (6%) atypical or malignant (<1%). For NAF, corresponding percentages were 6%, 3%, and fewer than 1%. Ductal lavage detected abnormal intraductal breast cells 3.2 times more often than nipple aspiration (79 versus 25 breasts; McNemar's test, P<.001). No serious procedure-related adverse events were reported.

CONCLUSIONS

Large numbers of ductal cells can be collected by ductal lavage to detect atypical cellular changes within the breast. Ductal lavage is a safe and well-tolerated procedure and is a more sensitive method of detecting cellular atypia than nipple aspiration.