Hereditary breast cancer growth rates and its impact on screening policy

Prolonged time to breast cancer surgery and the risk of metastasis: an explorative simulation analysis using epidemiological data from Germany and the USA

PURPOSE

Growing breast cancer is associated with an inherent risk of metastasis. If surgical treatment of breast cancer is delayed, the prognosis worsens with increasing tumor size. This justifies the search for a safe time interval between diagnosis and surgery.

METHODS

The 2022 population-based data on incidence and the time interval to initial surgery for the United States (U.S.) and Germany are used. Tumor growth and initiation of metastases can be calculated using public data on hormone receptor status, volume doubling time, and tumor size-dependent relative survival. Our assumptions are based on an initial 19.8 mm mean tumor size. 15-year BC-specific mortality in both countries is assumed to be 19.6% without surgical delay. Volume doubling time stratified by hormone receptor status, assumed to be continuous may differ by a factor of 2.4.

RESULTS

The U.S. and Germany report 287,850/71,375 new breast cancers for the year 2022 and 2019. If tumor removal is delayed by 8 weeks, mortality rate increases by 2.25/4.79% (HR + /HR-) as estimated by our model. The currently reported mean delay in the U.S. and Germany of 33.7/26.0 days or 4.8/3.7 weeks, respectively, would lead to an estimated 4,676/918 additional BC deaths or a 1.6/1.2% rise in the 15-year BC-specific mortality rate.

CONCLUSIONS

This study offers reasonable evidence that confirmed cases of breast cancer should be prioritized and treated according to hormone receptor status and tumor size as soon as possible. Effective screening measures should be followed by timely treatment.

Improving lesion volume measurements on digital mammograms

Lesion volume is an important predictor for prognosis in breast cancer. However, it is currently impossible to compute lesion volumes accurately from digital mammography data, which is the most popular and readily available imaging modality for breast cancer. We make a step towards a more accurate lesion volume measurement on digital mammograms by developing a model that allows to estimate lesion volumes on processed mammogram. Processed mammograms are the images routinely used by radiologists in clinical practice as well as in breast cancer screening and are available in medical centers. Processed mammograms are obtained from raw mammograms, which are the X-ray data coming directly from the scanner, by applying certain vendor-specific non-linear transformations. At the core of our volume estimation method is a physics-based algorithm for measuring lesion volumes on raw mammograms. We subsequently extend this algorithm to processed mammograms via a deep learning image-to-image translation model that produces synthetic raw mammograms from processed mammograms in a multi-vendor setting. We assess the reliability and validity of our method using a dataset of 1778 mammograms with an annotated mass. Firstly, we investigate the correlations between lesion volumes computed from mediolateral oblique and craniocaudal views, with a resulting Pearson correlation of 0.93 [95% confidence interval (CI) 0.92 - 0.93]. Secondly, we compare the resulting lesion volumes from true and synthetic raw data, with a resulting Pearson correlation of 0.998 [95%CI 0.998 - 0.998] . Finally, for a subset of 100 mammograms with a malignant mass and concurrent MRI examination available, we analyze the agreement between lesion volume on mammography and MRI, resulting in an intraclass correlation coefficient of 0.81 [95%CI 0.73 - 0.87] for consistency and 0.78 [95%CI 0.66 - 0.86] for absolute agreement. In conclusion, we developed an algorithm to measure mammographic lesion volume that reached excellent reliability and good validity, when using MRI as ground truth. The algorithm may play a role in lesion characterization and breast cancer prognostication on mammograms.

Tumor Doubling Time and Screening Interval

The goal of screening is to detect breast cancers when still curable to decrease breast cancer-specific mortality. Breast cancer screening in the United States is routinely performed with digital mammography and digital breast tomosynthesis. This article reviews breast cancer doubling time by tumor subtype and examines the impact of doubling time on breast cancer screening intervals. By the article's end, the reader will be better equipped to have informed discussions with patients and medical professionals regarding the benefits and disadvantages of the currently recommended screening mammography intervals.

Has tumor doubling time in breast cancer changed over the past 80 years? A systematic review

Over the past century, epidemiologic changes and implementation of screening may have had an impact on tumor doubling time in breast cancer. Our study was designed to evaluate changes in tumor doubling time in breast cancer over the past 80 years. A systematic review of published literature and meta-regression analysis was performed. An online electronic database search was undertaken using the PubMed platform from inception until June 2020. All studies that measured tumor doubling time in breast cancer were included. A total of 151 publications were retrieved. Among them, 16 full-text articles were included in the qualitative analysis. An exponential growth model was used for quantitative characterization of tumor growth rate. Tumor doubling time has remained stable over the past 80 years. Recent studies have not only identified "fast growing tumor" (grade 3, human epidermal growth factor receptor 2-positive, triple-negative, or tumor with an elevated Ki-67) but also "inactive breast cancer" feeding the ongoing debate of overdiagnosis due to screening programs. The stability of tumor doubling time over the past 80 years, despite increasing and changing risk factors, supports the validity for our screening guidelines. Prospective studies based on more precise measurement of tumor size and adjustment for tumor characteristics are necessary to more clearly characterize the prognostic and predictive impact of tumor doubling time in breast cancer.

Breast density implications and supplemental screening

Digital breast tomosynthesis (DBT) has been widely implemented in place of 2D mammography, although it is less effective in women with extremely dense breasts. Breast ultrasound detects additional early-stage, invasive breast cancers when combined with mammography; however, its relevant limitations, including the shortage of trained operators, operator dependence and small field of view, have limited its widespread implementation. Automated breast sonography (ABS) is a promising technique but the time to interpret and false-positive rates need to be improved. Supplemental screening with contrast-enhanced magnetic resonance imaging (MRI) in high-risk women reduces late-stage disease; abbreviated MRI protocols may reduce cost and increase accessibility to women of average risk with dense breasts. Contrast-enhanced digital mammography (CEDM) and molecular breast imaging improve cancer detection but require further validation for screening and direct biopsy guidance should be implemented for any screening modality. This article reviews the status of screening women with dense breasts. KEY POINTS: • The sensitivity of mammography is reduced in women with dense breasts. Supplemental screening with US detects early-stage, invasive breast cancers. • Tomosynthesis reduces recall rate and increases cancer detection rate but is less effective in women with extremely dense breasts. • Screening MRI improves early diagnosis of breast cancer more than ultrasound and is currently recommended for women at high risk. Risk assessment is needed, to include breast density, to ascertain who should start early annual MRI screening.

Timing and Delays in Breast Cancer Evaluation and Treatment

BACKGROUND

Even small delays in the treatment of breast cancer are a frequently expressed concern of patients. Knowledge about this subject is important for clinicians to counsel patients appropriately and realistically, while also optimizing care. Although data and quality measures regarding time to chemotherapy and radiotherapy have been present for some time, data regarding surgical care are more recent and no standard exists. This review was written to discuss our current knowledge about the relationship of treatment times to outcomes.

METHODS

The published medical literature addressing delays and optimal times to treatment was reviewed in the context of our current time-dependent standards for chemotherapy and radiotherapy. The surgical literature and the lack of a time-dependent surgical standard also were discussed, suggesting a possible standard.

RESULTS

Risk factors for delay are numerous, and tumor doubling times are both difficult to determine and unhelpful to assess the impact of longer treatment times on outcomes. Evaluation components also have a time cost and are inextricable from the patient's workup. Although the published literature has lack of uniformity, optimal times to each modality are strongly suggested by emerging data, supporting the current quality measures. Times to surgery, chemotherapy, and radiotherapy all have a measurable impact on outcomes, including disease-free survival, disease-specific survival, and overall survival.

CONCLUSIONS

Delays have less of an impact than often thought but have a measurable impact on outcomes. Optimal times from diagnosis are < 90 days for surgery, < 120 days for chemotherapy, and, where chemotherapy is administered, < 365 days for radiotherapy.

Breast and Tumour Volume Measurements in Breast Cancer Patients Using 3-D Automated Breast Volume Scanner Images

BACKGROUND

The resection volume in relation to the breast volume is known to influence cosmetic outcome following breast-conserving therapy. It was hypothesised that three-dimensional ultrasonography (3-D US) could be used to preoperatively assess breast and tumour volume and show high association with histopathological measurements.

METHODS

Breast volume by the 3D-US was compared to the water displacement method (WDM), mastectomy specimen weight, 3-D MRI and three different calculations for breast volume on mammography. Tumour volume by the 3-D US was compared to the histopathological tumour volume and 3-D MRI. Relatedness was based on the intraclass correlation coefficient (ICC) with corresponding 95% confidence interval (95% CI). Bland-Altman plots were used to graphically display the agreement for the different assessment techniques. All measurements were performed by one observer.

RESULTS

A total of 36 patients were included, 20 and 23 for the evaluation of breast and tumour volume (ductal invasive carcinomas), respectively. 3-D US breast volume showed 'excellent' association with WDM, ICC 0.92 [95% CI (0.80-0.97)]. 3-D US tumour volume showed a 'excellent' association with histopathological tumour volume, ICC 0.78 [95% CI (0.55-0.91)]. Bland-Altman plots showed an increased overestimation in lager tumour volumes measured by 3-D MRI compared to histopathological volume.

CONCLUSIONS

3-D US showed a high association with gold standard WDM for the preoperative assessment of breast volume and the histopathological measurement of tumour volume. 3-D US is an patient-friendly preoperative available technique to calculate both breast volume and tumour volume. Volume measurements are promising in outcome prediction of intended breast-conserving treatment.

BRCA mutation in breast cancer patients: Prognostic impact and implications on clinical management

BRCA1/2 mutations are involved in breast cancer (BC) susceptibility but their influence on outcome is unclear. We reviewed BC patients tested for BRCA to determine biological features and influence on outcome. BRCA-1 was correlated to younger age (P = 0.035), nodal involvement (P = 0.030), higher tumor grade (P = 0.0022) and Ki-67 (P = 0.014), ER/PgR negative status (P = 0.00042 and 0.0091, respectively), and use of adjuvant chemotherapy (P = 0.000038); BRCA was neither predictive for chemotherapy administration nor resulted in impaired outcome or occurrence of secondary BC. BRCA status did not influence outcome despite higher biological aggressiveness and younger age at presentation.

Is there a Specific Magnetic Resonance Phenotype Characteristic of Hereditary Breast Cancer?

Aims and background

The aim of the study was to investigate the growth rate of inherited breast cancer, to analyze its T2 signal intensity besides kinetic and morphologic aspects, and to verify whether there is any correlation between magnetic resonance imaging phenotype and BRCA status.

Methods

Between June 2000 and September 2009, we enrolled 227 women at high genetic risk for breast cancer in a surveillance program, within a multicenter project of the Istituto Superiore di Sanità (Rome).

Results

Thirty-four cancers were detected among 31 subjects. One patient refused magnetic resonance imaging because of claustrophobia. Compared with sporadic disease, hereditary cancer showed some differences, in terms of biologic attitude and semeiotic patterns. These differences were mainly registered for magnetic resonance imaging, where the most frequent radiological variant was represented by the very high T2 signal intensity (73%). Moreover, the size of 8 of the neoplasms showed a significant increase in less than one year, 5 of them in less than 6 months. Six lesions were in BRCA1 patients and the remaining in BRCA2. Furthermore, cancers with a high growth rate also demonstrated a significant increment in T2 signal intensity.

Conclusions

Our results confirmed the high growth rate within BRCA-related breast cancers, especially for BRCA1 mutation carriers. In our experience, we found a specific imaging phenotype, represented by the high T2 signal intensity of hereditary breast cancer. To our knowledge, this is the first report that points out this new semeiotic parameter, which is usually typical of benign lesions. Considering the correlation between high growth rate and high T2 signal intensity, the former seems to be related to the absence of induction of a desmoplastic reaction that could somehow restrict cancer growth.

Underutilization of Supplemental Magnetic Resonance Imaging Screening Among Patients at High Breast Cancer Risk

BACKGROUND

Women at high lifetime breast cancer risk may benefit from supplemental breast magnetic resonance imaging (MRI) screening, in addition to routine mammography screening for earlier cancer detection.

MATERIALS AND METHODS

We performed a cross-sectional study of 422,406 women undergoing routine mammography screening across 86 Breast Cancer Surveillance Consortium (BCSC) facilities during calendar year 2012. We determined availability and use of on-site screening breast MRI services based on woman-level characteristics, including >20% lifetime absolute risk using the National Cancer Institute risk assessment tool. Multivariate analyses were performed to determine sociodemographic characteristics associated with on-site screening MRI use.

RESULTS

Overall, 43.9% (2403/5468) of women at high lifetime risk attended a facility with on-site breast MRI screening availability. However, only 6.6% (158/2403) of high-risk women obtained breast MRI screening within a 2-year window of their screening mammogram. Patient factors associated with on-site MRI screening use included younger (<40 years) age (odds ratio [OR] = 2.39, 95% confidence interval [CI]: 1.34-4.21), family history (OR = 1.72, 95% CI: 1.13-2.63), prior breast biopsy (OR = 2.09, 95% CI: 1.22-3.58), and postsecondary education (OR = 2.22, 95% CI: 1.04-4.74).

CONCLUSIONS

While nearly half of women at high lifetime breast cancer risk undergo routine screening mammography at a facility with on-site breast MRI availability, supplemental breast MRI remains widely underutilized among those who may benefit from earlier cancer detection. Future studies should evaluate whether other enabling factors such as formal risk assessment and patient awareness of high lifetime breast cancer risk can mitigate the underutilization of supplemental screening breast MRI.

Growth rate of invasive ductal carcinomas from a screened 50-74-year-old population

Objective As breast cancer growth rate is associated with menopause, most screening programmes target mainly women aged 50-74. We studied the association between age at diagnosis and growth rate in this screening-specific age range. Methods We used data from breast cancer patients diagnosed in the screening programme in Nijmegen, the Netherlands. The data were restricted to the screening rounds when analogue mammography was used in both the screening and clinical setting. Growth rate expressed as tumour volume doubling time was based on increasing tumour size in longitudinal series of mammograms. Estimates were based on (a) tumours showing at least two measurable shadows, (b) tumours showing a shadow at detection only (left censored), and (c) tumours showing no growth (right-censored observation). All 293 tumours were consecutively diagnosed invasive ductal breast cancers in participants of the Nijmegen screening programme in the period 2000-2007. Results Depending on the assumptions made on tumour margins and mammographic density, the relation of volume doubling time with age non-significantly varies from a decrease of 3.3% to an increase of 1.4% for each year increase in age at diagnosis (all P-values ≥ 0.18). Applying left censoring on indistinct tumours, the geometric mean volume doubling time was 191 days (95% confidence interval 158-230). Conclusion We found no significant change in growth rate with age in women diagnosed with invasive ductal breast cancer in the screening age range 50-74. This outcome does not support differential screening intervals by age based solely on breast cancer growth rate for this particular group.

Imaging surveillance programs for women at high breast cancer risk in Europe: Are women from ethnic minority groups adequately included? (Review)

Women from ethnic minority groups, including immigrants and refugees are reported to have low breast cancer (BC) screening rates. Active, culturally-sensitive outreach is vital for increasing participation of these women in BC screening programs. Women at high BC risk and who belong to an ethnic minority group are of special concern. Such women could benefit from ongoing trials aimed at optimizing screening strategies for early BC detection among those at increased BC risk. Considering the marked disparities in BC survival in Europe and its enormous and dynamic ethnic diversity, these issues are extremely timely for Europe. We systematically reviewed the literature concerning European surveillance studies that had imaging in the protocol and that targeted women at high BC risk. The aim of the present review was thereby to assess the likelihood that women at high BC risk from minority ethnic groups were adequately included in these surveillance programs. Twenty-seven research groups in Europe reported on their imaging surveillance programs for women at increased BC risk. The benefit of strategies such as inclusion of magnetic resonance imaging and/or more intensive screening was clearly documented for the participating women at increased BC risk. However, none of the reports indicated that sufficient outreach was performed to ensure that women at increased BC risk from minority ethnic groups were adequately included in these surveillance programs. On the basis of this systematic review, we conclude that the specific screening needs of ethnic minority women at increased BC risk have not yet been met in Europe. Active, culturally-sensitive outreach is needed to identify minority women at increased BC risk and to facilitate their inclusion in on-going surveillance programs. It is anticipated that these efforts would be most effective if coordinated with the development of European-wide, population-based approaches to BC screening.

Breast cancer screening: an evidence-based update

Routine screening mammography is recommended by most groups issuing breast cancer screening guidelines, especially for women 50 years of age and older. However, both the potential benefits and risks of screening should be discussed with individual patients to allow for shared decision making regarding their participation in screening, age of commencement and conclusion, and interval of mammography screening.

Preoperative prediction of cosmetic results in breast conserving surgery

BACKGROUND

Preoperative objective predictions of cosmetic result after breast conserving surgery (BCS) has the potential to aid in surgical treatment decision making. Our aim was to investigate the predictive value of tumor volume in relation to breast volume (TV/BV ratio) for cosmetic result.

METHODS

Sixty-nine invasive breast cancer women with preoperative MRI and treated by BCS and radiotherapy in 2007-2012 were prospectively included. Simple excision or basic oncoplastic techniques were used, but no volume displacement. TV/BV ratio was measured in the MRI while 3D-projected in virtual reality environment (I-Space). Cosmetic result was assessed by patient questionnaire, panel evaluation, and breast retraction assessment (BRA). Quality-of-life was assessed by EORTC QLQ-C30 and BR23.

RESULTS

Intraobserver and interobserver correlation coefficients for tumor and breast volume were all >0.95. Increasing TV/BV ratio correlated with decreasing cosmetic result as determined by patient, panel, and BRA. TV/BV ratio was a significant independent predictor for the panel evaluation (P=0.028), as was tumor location (P<0.05), and together they constituted a good prediction model (AUC 0.83).

CONCLUSIONS

TV/BV ratio was a precise and independent predictor for cosmetic result determined by a panel and can be used as preoperative prediction tool to enable more informed surgical treatment decision making.

Supplemental screening ultrasound increases cancer detection yield in BRCA1 and BRCA2 mutation carriers

INTRODUCTION

This study aimed at evaluating the efficacy of ultrasound for the early detection of breast cancers in BRCA1/2 mutation carriers.

METHODS

Between 01/1997 and 10/2008 221 BRCA1/2 mutation carriers participated in a breast cancer screening program which included semi-annual ultrasound in combination with annual mammography and magnetic resonance imaging (MRI). Women underwent on average (median) five semi-annual screening rounds with a range of one to 22 appointments, totaling 1,855 rounds of screening. All three imaging modalities were coded according to the American College of Radiology (BI-RADS classification).

RESULTS

In total, we detected 27 BRCA-associated breast cancers in 25 patients. The sensitivity was 77% for ultrasound, 27% for mammography, and 100% for MRI. Three tumors were detected directly as a result of only the semi-annual ultrasound screen.

CONCLUSIONS

Due to the specific tumor morphology and the considerably elevated tumor doubling time, mutation carriers benefit from the addition of semi-annual ultrasound screening as a sensitive and cost-effective method.

Detection of cancer before distant metastasis

Background

To establish a distant metastasis (DM) cells must disseminate from the primary tumor and overcome a series of obstacles, the metastatic cascade. In this study we develop a mathematical model for this cascade to estimate the tumor size and the circulating tumor cell (CTC) load before the first metastasis has formed from a primary breast cancer tumor.

Methods

The metastatic cascade is described in discrete steps: 1. local tumor growth; 2. dissemination into circulation; 3. survival in circulation; 4. extravasation into tissue; and 5. growth into a metastasis. The model was built using data and relationships described in the literature to predict the relationship between tumor size and probability of distant metastasis for 38715 patients with surgically removed T_XN_XM₀ primary breast cancer from the Netherlands Cancer Registry. The model was calibrated using primary tumor size, probability of distant metastasis and time to distant metastasis for 1489 patients with stage T_1BN_XM₀ (25% of total patients with T_1BN_XM₀). Validation of the model was done with data for all patients.

Results

From the time to distant metastasis of these 38715 breast cancer patients, we determined a tumor doubling time of 1.7 ± 0.9 months. Fitting the data for 25% of T_1B patients estimates a metastatic efficiency of 1 metastasis formed per 60 million disseminated tumor cells. Validation of the model to data of patients in all T-stages shows good agreement between model and epidemiological data. To reduce the 5-year risk of distant metastasis for T_XN_XM₀ from 9.2% to 1.0%, the primary tumor needs to be detected and removed before it reaches a diameter of 2.7 ± 1.6 mm. At this size, the model predicts that there will be 9 ± 6 CTC/L blood.

Conclusions

To reduce the rate of distant metastasis in surgically treated T_XN_XM₀ breast cancer to 1%, imaging technology will need to be able to detect lesions of 2.7 mm in diameter or smaller. Before CTC detection can be applied in the early disease setting, sensitivity will need to be improved by at least 15-fold and combined with technology that minimizes false positives.

Breast Cancer Incidence After Risk-Reducing Salpingo-Oophorectomy in BRCA1 and BRCA2 Mutation Carriers

Premenopausal risk-reducing salpingo-oophorectomy (RRSO) in BRCA1/2 mutation carriers effectively reduces ovarian cancer risk, but also reduces breast cancer risk. Breast cancer risk reductions up to 50% have been reported for both BRCA1 and BRCA2 mutation carriers, but recent prospective studies were not able to reproduce this finding for BRCA1 mutation carriers. Breast cancer incidence after RRSO was assessed in a consecutive series of 104 BRCA1 and 58 BRCA2 mutation carriers. On the basis of data from our own centre, and assuming a 50% risk reduction through RRSO at premenopausal age, we expected to find 8 breast cancers (range 6-10) in this population for the reported screening period (532 women-years). In 162 carriers with a median age of 41 years at RRSO, 13 incident breast cancers were diagnosed. In BRCA1 mutation carriers, 12 incident breast cancers were found compared with 5 (range 3-6) expected and in BRCA2 mutation carriers 1 breast cancer was found compared with 3 (range 2-5) expected. Breast cancer incidence after premenopausal RRSO is still high, especially in BRCA1 mutation carriers. Previously reported breast cancer risk reductions up to 50% were not confirmed. As a consequence, continued intensive screening for breast cancer is warranted in BRCA1 and BRCA2 mutation carriers after RRSO.

Positive lymph nodes do not metastasize

Our understanding of the role of lymph nodes (LN) in the metastasization process (MET) is marginal. Positive LNs (pLN) are the most important prognostic factor and lymph node dissection (LND) is still standard practice in primary treatment. However, up to now, there is almost no evidence that elective LND has a survival benefit. Based on many clinical and experimental findings, we propose that tumor foci in regional LN are incapable of metastasization and can therefore not infiltrate further LN and organs. Available data demonstrate a very early infiltration of MET capable tumor cells from the primary tumor into regional LN, and thereafter an increased probability of subsequent LN infiltrations. Disparate growth rates of the first versus subsequent infiltrating tumors as well as the asymptotic growth and prognosis of large tumor foci in LN explain many clinical observations for solid tumors. The consequence of the hypothesis "pLN do not metastasize" would impact clinical treatment and research and contribute to understanding the mounting evidence against LND.

Inhibitors targeting mitosis: tales of how great drugs against a promising target were brought down by a flawed rationale

Although they have been advocated with an understandable enthusiasm, mitosis-specific agents such as inhibitors of mitotic kinases and kinesin spindle protein have not been successful clinically. These drugs were developed as agents that would build on the success of microtubule-targeting agents while avoiding the neurotoxicity that encumbers drugs such as taxanes and vinca alkaloids. The rationale for using mitosis-specific agents was based on the thesis that the clinical efficacy of microtubule-targeting agents could be ascribed to the induction of mitotic arrest. However, the latter concept, which has long been accepted as dogma, is likely important only in cell culture and rapidly growing preclinical models, and irrelevant in patient tumors, where interference with intracellular trafficking on microtubules is likely the principal mechanism of action. Here we review the preclinical and clinical data for a diverse group of inhibitors that target mitosis and identify the reasons why these highly specific, myelosuppressive compounds have failed to deliver on their promise.

The p53 network: cellular and systemic DNA damage responses in aging and cancer

Genome instability contributes to cancer development and accelerates age-related pathologies as evidenced by a variety of congenital cancer susceptibility and progeroid syndromes that are caused by defects in genome maintenance mechanisms. DNA damage response (DDR) pathways that are mediated through the tumor suppressor p53 play an important role in the cell-intrinsic responses to genome instability, including a transient cell cycle arrest, senescence and apoptosis. Both senescence and apoptosis are powerful tumor-suppressive pathways preventing the uncontrolled proliferation of transformed cells. However, both pathways can potentially deplete stem and progenitor cell pools, thus promoting tissue degeneration and organ failure, which are both hallmarks of aging. p53 signaling is also involved in mediating non-cell-autonomous interactions with the innate immune system and in the systemic adjustments during the aging process. The network of p53 target genes thus functions as an important regulator of cancer prevention and aging.

Prophylactic and Therapeutic Breast Conservation in BRCA1/2 Mutation Carriers

Breast-conserving therapy (BCT) for sporadic breast cancer has been widely accepted by surgeons and patients alike. While BCT is associated with a higher risk of ipsilateral breast tumor recurrence (IBTR), it has not been shown to decrease overall survival (OS) in comparison with mastectomy. Many women with a BRCA1/2 mutation opt for mastectomy instead of breast-conserving measures at the time of a breast cancer diagnosis. In some cases, this is due to fear of aggressive disease, but to date, there have been no studies offering strong evidence that breast conservation should not be offered to these women. BRCA1/2-associated breast cancer has not been found to be more aggressive or resistant to treatment than comparable sporadic tumors, and no study has shown an actual survival advantage for mastectomy in appropriately treated affected mutation carriers. This paper reviews the available literature for breast conservation and surgical decision making in BRCA1/2 mutation carriers.

Hereditary breast and ovarian cancer: new genes, new treatments, new concepts

BACKGROUND

Every year, 60,000 women in Germany are found to have breast cancer, and 9000 to have ovarian cancer. Familial clustering of carcinoma is seen in about 20% of cases.

METHODS

We selectively review relevant articles published up to December 2010 that were retrieved by a search in PubMed, and we also discuss findings from the experience of the German Consortium for Hereditary Breast and Ovarian Cancer.

RESULTS

High risk is conferred by the highly penetrant BRCA1 and BRCA2 genes as well as by other genes such as RAD51C. Genes for breast cancer that were originally designated as moderately penetrant display higher penetrance than previously thought in families with a hereditary predisposition. The role these genes play in DNA repair is thought to explain why tumors associated with them are sensitive to platin derivatives and PARP inhibitors. In carriers of BRCA1 and BRCA2, prophylactic bilateral mastectomy and adnexectomy significantly lowers the incidence of breast and ovarian cancer. Moreover, prophylactic adnexectomy also lowers the breast-and-ovarian-cancer-specific mortality, as well as the overall mortality. If a woman bearing a mutation develops cancer in one breast, her risk of developing cancer in the other breast depends on the particular gene that is mutated and on her age at the onset of disease.

CONCLUSION

About half of all monogenically determined carcinomas of the breast and ovary are due to a mutation in one or the other of the highly penetrant BRCA genes (BRCA1 and BRCA2). Women carrying a mutated gene have an 80% to 90% chance of developing breast cancer and a 20% to 50% chance of developing ovarian cancer. Other predisposing genes for breast and ovarian cancer have been identified. Clinicians should develop and implement evidence-based treatments on the basis of these new findings.

Growth of breast cancer recurrences assessed by consecutive MRI

Background

Women with a personal history of breast cancer have a high risk of developing an ipsi- or contralateral recurrence. We aimed to compare the growth rate of primary breast cancer and recurrences in women who had undergone prior breast magnetic resonance imaging (MRI).

Methods

Three hundred and sixty-two women were diagnosed with breast cancer and had undergone breast MRI at the time of diagnosis in our institution (2005 - 2009). Among them, 37 had at least one prior breast MRI with the lesion being visible but not diagnosed as cancer. A linear regression of tumour volume measured on MRI scans and time data was performed using a generalized logistic model to calculate growth rates. The primary objective was to compare the tumour growth rate of patients with either primary breast cancer (no history of breast cancer) or ipsi- or contralateral recurrences of breast cancer.

Results

Twenty women had no history of breast cancer and 17 patients were diagnosed as recurrences (7 and 10 were ipsi- and contralateral, respectively). The tumour growth rate was higher in contralateral recurrences than in ipsilateral recurrences (growth rate [10^-3 days^-1] 3.56 vs 1.38, p < .001) or primary cancer (3.56 vs 2.09, p = 0.01). Differences in tumour growth were not significant for other patient-, tumour- or treatment-related characteristics.

Conclusions

These findings suggest that contralateral breast cancer presents accelerated growth compared to ipsilateral recurrences or primary breast events.

BRCA1-Associated Breast Cancers Present Differently From BRCA2-Associated and Familial Cases: Long-Term Follow-Up of the Dutch MRISC Screening Study

Purpose

The Dutch MRI Screening Study on early detection of hereditary breast cancer started in 1999. We evaluated the long-term results including separate analyses of BRCA1 and BRCA2 mutation carriers and first results on survival.

Patients and Methods

Women with higher than 15% cumulative lifetime risk (CLTR) of breast cancer were screened with biannual clinical breast examination and annual mammography and magnetic resonance imaging (MRI). Participants were divided into subgroups: carriers of a gene mutation (50% to 85% CLTR) and two familial groups with high (30% to 50% CLTR) or moderate risk (15% to 30% CLTR).

Results

Our update contains 2,157 eligible women including 599 mutation carriers (median follow-up of 4.9 years from entry) with 97 primary breast cancers detected (median follow-up of 5.0 years from diagnosis). MRI sensitivity was superior to that of mammography for invasive cancer (77.4% v 35.5%; P < .00005), but not for ductal carcinoma in situ. Results in the BRCA1 group were worse compared to the BRCA2, the high-, and the moderate-risk groups, respectively, for mammography sensitivity (25.0% v 61.5%, 45.5%, 46.7%), tumor size at diagnosis ≤ 1 cm (21.4% v 61.5%, 40.9%, 63.6%), proportion of DCIS (6.5% v 18.8%, 14.8%, 31.3%) and interval cancers (32.3% v 6.3%, 3.7%, 6.3%), and age at diagnosis younger than 30 years (9.7% v 0%). Cumulative distant metastasis-free and overall survival at 6 years in all 42 BRCA1/2 mutation carriers with invasive breast cancer were 83.9% (95% CI, 64.1% to 93.3%) and 92.7% (95% CI, 79.0% to 97.6%), respectively, and 100% in the familial groups (n = 43).

Conclusion

Screening results were somewhat worse in BRCA1 mutation carriers, but 6-year survival was high in all risk groups.

Prospective multicenter cohort study to refine management recommendations for women at elevated familial risk of breast cancer: the EVA trial

PURPOSE

We investigated the respective contribution (in terms of cancer yield and stage at diagnosis) of clinical breast examination (CBE), mammography, ultrasound, and quality-assured breast magnetic resonance imaging (MRI), used alone or in different combination, for screening women at elevated risk for breast cancer.

METHODS

Prospective multicenter observational cohort study. Six hundred eighty-seven asymptomatic women at elevated familial risk (> or = 20% lifetime) underwent 1,679 annual screening rounds consisting of CBE, mammography, ultrasound, and MRI, read independently and in different combinations. In a subgroup of 371 women, additional half-yearly ultrasound and CBE was performed more than 869 screening rounds. Mean and median follow-up was 29.18 and 29.09 months.

RESULTS

Twenty-seven women were diagnosed with breast cancer: 11 ductal carcinoma in situ (41%) and 16 invasive cancers (59%). Three (11%) of 27 were node positive. All cancers were detected during annual screening; no interval cancer occurred; no cancer was identified during half-yearly ultrasound. The cancer yield of ultrasound (6.0 of 1,000) and mammography (5.4 of 1,000) was equivalent; it increased nonsignificantly (7.7 of 1,000) if both methods were combined. Cancer yield achieved by MRI alone (14.9 of 1,000) was significantly higher; it was not significantly improved by adding mammography (MRI plus mammography: 16.0 of 1,000) and did not change by adding ultrasound (MRI plus ultrasound: 14.9 of 1,000). Positive predictive value was 39% for mammography, 36% for ultrasound, and 48% for MRI.

CONCLUSION

In women at elevated familial risk, quality-assured MRI screening shifts the distribution of screen-detected breast cancers toward the preinvasive stage. In women undergoing quality-assured MRI annually, neither mammography, nor annual or half-yearly ultrasound or CBE will add to the cancer yield achieved by MRI alone.

Cancers in BRCA1 and BRCA2 carriers and in women at high risk for breast cancer: MR imaging and mammographic features

PURPOSE

To review imaging features of screening-detected cancers on images from diagnostic and prior examinations to identify specific abnormalities to aid earlier detection of or facilitate differentiation of cancers in BRCA1 and BRCA2 carriers and in women with a high risk for breast cancer.

MATERIALS AND METHODS

Informed consent and multicenter and local research ethics committee approval were obtained. Women (mean age, 40.1 years; range, 27-55 years) who had at least a 50% risk of being a BRCA1, BRCA2, or TP53 gene mutation carrier were recruited from August 1997 to March 2003 into the United Kingdom Magnetic Resonance Imaging in Breast Screening Study Group trial and were offered annual magnetic resonance (MR) imaging and two-view mammography (total number of screenings, 2065 and 1973; mean, 2.38 and 2.36, respectively). Images in all 39 cancer cases were reread in consensus to document the morphologic and enhancement imaging features on MR and mammographic images in screening and prior examinations. Cases were grouped into genetic subtypes.

RESULTS

With MR imaging, there was no difference in morphologic or enhancement characteristics between the genetic subgroups. Cancers on images from prior examinations were of smaller size, showed less enhancement, and were more likely to have a type 1 enhancement curve compared with those cancers in the subsequent diagnostic screening examinations. The tumor sizes detected by using MR imaging and mammography were not significantly different (P = .46). The cancers in BRCA1 carriers found by using MR imaging tended to be smaller than those detected by using mammography (median, 17 mm vs 30 mm; P = .37), whereas the opposite was true for cancers found in BRCA2 carriers (MR imaging median size = 12.5 mm vs mammographic median size = 6 mm; P = .067); the difference was not significant. Tumors with prior MR imaging abnormalities grew at an average of 5.1 mm/y.

CONCLUSION

When undertaking MR imaging surveillance in high-risk women, small enhancing lesions should be regarded with suspicion and biopsied or patients should be followed up at 6 months.

Breast cancer after use of estrogen plus progestin in postmenopausal women

BACKGROUND

Following the release of the 2002 report of the Women's Health Initiative (WHI) trial of estrogen plus progestin, the use of menopausal hormone therapy in the United States decreased substantially. Subsequently, the incidence of breast cancer also dropped, suggesting a cause-and-effect relation between hormone treatment and breast cancer. However, the cause of this decrease remains controversial.

METHODS

We analyzed the results of the WHI randomized clinical trial--in which one study group received 0.625 mg of conjugated equine estrogens plus 2.5 mg of medroxyprogesterone acetate daily and another group received placebo--and examined temporal trends in breast-cancer diagnoses in the WHI observational-study cohort. Risk factors for breast cancer, frequency of mammography, and time-specific incidence of breast cancer were assessed in relation to combined hormone use.

RESULTS

In the clinical trial, there were fewer breast-cancer diagnoses in the group receiving estrogen plus progestin than in the placebo group in the initial 2 years of the study, but the number of diagnoses increased over the course of the 5.6-year intervention period. The elevated risk decreased rapidly after both groups stopped taking the study pills, despite a similar frequency of mammography. In the observational study, the incidence of breast cancer was initially about two times as high in the group receiving menopausal hormones as in the placebo group, but this difference in incidence decreased rapidly in about 2 years, coinciding with year-to-year reductions in combined hormone use. During this period, differences in the frequency of mammography between the two groups were unchanged.

CONCLUSIONS

The increased risk of breast cancer associated with the use of estrogen plus progestin declined markedly soon after discontinuation of combined hormone therapy and was unrelated to changes in frequency of mammography.

Stage of breast cancers found during the surveillance of women with a familial or hereditary risk

AIM

To compare the breast cancer stages found during MG alone surveillance in women at increased risk with those detected in a program where MRI was added.

METHODS

Stage results of in a retrospective MG alone study of prospectively followed patients, compared with the pooled stage results of breast cancers MG/MRI surveillance.

RESULTS

One hundred and-fifty-one patients were detected with a first or contralateral breast cancer. Interval cancers were diagnosed in 56% of the BRCA1, 42% of the BRCA2 and 28% of the non-BRCA carriers. A considerable proportion of the breast cancers were detected with breast self-examination alone: 41%, 27% and 31% respectively. Nevertheless the established goals for biennial population screening were reached, except for the BRCA2 carriers, but this group was small. Comparison with pooled data from published MG/MRI surveillance studies did not show significant differences in the stages, except for the BRCA2 carriers.

CONCLUSION

Breast cancers detected in a MG alone surveillance program for women at increased risk fulfill most goals set for population screening except for the BRCA2 carriers. Breast self-examination appears to be a valuable additional detection method especially for BRCA1 carriers, who are at risk of developing a highly proliferating breast cancer.

BRCA1--sowing the seeds crooked in the furrow

Breast tumors with deficiency in DNA double-strand break repair might be expected to show aneuploidy. A new study shows that microdeletions in PTEN, resulting in complete loss of PTEN protein, are signature lesions in these cancers, particularly those arising in BRCA1-mutation carriers.

Screening for hereditary breast cancer

Most women at risk for hereditary breast cancer opt for intensive breast screening rather than risk-reducing mastectomy. For this to be a rational choice, the vast majority of tumors must be detected either while still in situ or at a very early stage of invasion. Annual screening mammography has low sensitivity in this population, in part due to the greater breast density of younger women, resulting in cancers being detected at a suboptimal stage. In six prospective comparative studies, the addition of annual contrast-enhanced magnetic resonance imaging (MRI) of the breast to mammography demonstrated greater than 90% sensitivity, more than twice that of mammography alone. In those studies that included ultrasound and clinical breast examination, additional cancers were rarely detected by these modalities. False positive rates were higher with the addition of MRI, but specificity improved on successive rounds of screening. Although long-term survival data are still lacking, there is mounting evidence that the addition of screening MRI to mammography detects hereditary breast cancers at an earlier stage and is thus estimated to be cost-effective, at least for women with BRCA mutations. This review will examine the literature and current screening recommendations.

[Hereditary breast and ovarian cancer: primary and secondary prevention for BRCA1 and BRCA2 mutation carriers]

Ten years after the identification of the breast and ovarian cancer predisposition genes, BRCA1 and BRCA2, an emerging literature has explored the efficacy of strategies for primary as well as secondary prevention of breast and ovarian cancer in BRCA1 and BRCA2 mutations carriers. The integration of magnetic resonance imaging for breast cancer screening in BRCA carriers has achieved a higher sensibility of the screening, and an early detection of breast cancer. However, we don't have yet enough level of evidence that magnetic resonance imaging could reduce mortality in BRCA carriers. Because of the limitations of screening for ovarian cancer, bilateral prophylactic salpingo-oophorectomy has been established as one of the most effective strategies to prevent ovarian cancer in BRCA1 and BRCA2 mutation carriers. This strategy also has a favorable effect on the reduction of risk of breast cancer if is performed before the age of 50. The management of this patients must be individualized and multidisciplinary.

Multicenter comparative multimodality surveillance of women at genetic-familial high risk for breast cancer (HIBCRIT study): interim results

PURPOSE

To prospectively compare clinical breast examination (CBE), mammography, ultrasonography (US), and contrast material-enhanced magnetic resonance (MR) imaging for screening women at genetic-familial high risk for breast cancer and report interim results, with pathologic findings as standard.

MATERIALS AND METHODS

Institutional review board of each center approved the research; informed written consent was obtained. CBE, mammography, US, and MR imaging were performed for yearly screening of BRCA1 or BRCA2 mutation carriers, first-degree relatives of BRCA1 or BRCA2 mutation carriers, or women enrolled because of a strong family history of breast or ovarian cancer (three or more events in first- or second-degree relatives in either maternal or paternal line; these included breast cancer in women younger than 60 years, ovarian cancer at any age, and male breast cancer at any age).

RESULTS

Two hundred seventy-eight women (mean age, 46 years +/- 12 [standard deviation]) were enrolled. Breast cancer was found in 11 of 278 women at first round and seven of 99 at second round (14 invasive, four intraductal; eight were <or=10 mm in diameter). Detection rate per year was 4.8% (18 of 377) overall; 4.3% (11 of 258) in BRCA1 or BRCA2 mutation carriers and first-degree relatives of BRCA1 or BRCA2 mutation carriers versus 5.9% (seven of 119) in women enrolled because of strong family history; and 5.3% (nine of 169) in women with previous personal breast and/or ovarian cancer versus 4.3% (nine of 208) in those without. In six (33%) of 18 patients, cancer was detected only with MR imaging. Sensitivity was as follows: CBE, 50% (95% confidence interval [CI]: 29%, 71%); mammography, 59% (95% CI: 36%, 78%); US, 65% (95% CI: 41%, 83%); and MR imaging, 94% (95% CI: 82%, 99%). Positive predictive value was as follows: CBE, 82% (95% CI: 52%, 95%); mammography, 77% (95% CI: 50%, 92%); US, 65% (95% CI: 41%, 83%); and MR imaging, 63% (95% CI: 43%, 79%).

CONCLUSION

Addition of MR imaging to the screening regimen for high-risk women may enable detection of otherwise unsuspected breast cancers.

Outcome of a structured surveillance programme in women with a familial predisposition for breast cancer

We aimed to prospectively evaluate the efficacy of a multi-modal surveillance programme for the early detection of familial breast cancer. Ultrasound, mammography and breast magnetic resonance imaging were evaluated in 413 women who participated in a prospective study with a median follow-up of 2.2 years (range 1-6.75 years). Of these, 49 women carried a BRCA mutation, 203 were at high and 161 at moderate risk. Breast carcinomas diagnosed within the programme were compared with 297 carcinomas previously observed in the risk group and 7894 carcinomas documented in the regional cancer registry within the same time period. Overall, 41 breast carcinomas and no interval carcinoma were detected. The detection rates averaged 107.2/1000 for mutation carriers with highest rates between 20 and 39 years of age, 45.8/1000 for high-risk women with highest rates between 40 and 49 years of age and 23.9/1000 for moderate-risk women with highest rates between 50 and 74 years of age. Overall, 82.8% of the breast carcinomas were node negative and 85.4% pre-invasive or smaller than 2 cm. In comparison, of breast carcinomas detected outside the programme only 47.8% were node negative (P=0.0005) and 43.8% pre-invasive or smaller than 2 cm (P<0.000 01). Of those gathered in the local cancer registry 55.7% were node negative (P=0.004) and 47.6% pre-invasive or smaller than 2 cm (P<0.000 01). Our data indicate that (1) there is a strong correlation between breast cancer detection rates, risk status and age at disease onset and (2) a multi-modal surveillance programme can detect early-stage hereditary breast carcinomas.

Psychosocial and Psychodynamic Factors Influencing Health Care Utilisation

This paper aims to elucidate some dysfunctional aspects of health care utilisation by combining concepts from modern systems theory and from psychoanalysis. Contemporary health care in industrialised countries can be conceived as a social system in terms of modern systems theory. According to this theory, social systems are operating on the basis of a 'guiding difference,' which in the case of health care is the distinction between 'healthy' and 'ill.' Its rigidity in adhering to the healthy-ill dichotomy exposes health care to being collusively entangled in the interpersonal defence arrangements of patients. In the psychoanalytic view, individual conflicts can be warded off from consciousness not only by intrapsychic defence, but also by interpersonal defence mechanisms. These mechanisms involve the patients' close social environment, often including doctors and hospitals. The functioning and the motivational structure of health care itself shows features of neurotic defence: not only its representatives, but health care as a whole act in a rigid, obsessive manner in order to separate the healthy from the ill and to battle against (presumed) diseases. This obsession sometimes results in excessive diagnostic activism and in inconsiderate application of aggressive medical treatments. Both are inappropriate with regard to the salient problem of modern medicine: the increase of chronic nonfatal diseases like depression and chronic pain. The described defence mechanisms are unconscious not only to patients but also to health care professionals (let alone health politicians), and are contributing to dysfunctional health care overuse.

Selection bias influences reported contralateral breast cancer incidence and survival in high risk non-BRCA1/2 patients

PURPOSE

The results of studies comparing survival in familial and sporadic breast cancer (BC) are inconsistent. A higher incidence of contralateral breast cancer (CBC) has been reported in familial BC. Ascertainment bias may influence both the reported familial CBC and survival.

DESIGN

We assessed CBC incidence, distant disease free (DDFS) and overall survival (OS) in 327 BC patients who had > or =3 breast and/or ovarian cancers in the family but no BRCA1/2 gene mutation (non-BRCA1/2). They were matched to 327 sporadic controls for year and age at detection. To correct for ascertainment bias, we analyzed also separately the results (1) Of the 250 non-BRCA1/2 patients with DNA testing performed before diagnosis or within 2 years ('unselected') and (2) Of the 77 with testing > or =2 years after diagnosis (late-tested).

RESULTS

Median follow-up of non-BRCA1/2 patients was 6.1 yrs. Ten years CBC incidence was 11% in non-BRCA1/2 versus 6% in sporadic patients (p = 0.002). At multivariate analysis CBC incidence was increased in late-tested non-BRCA1/2 (HR 4.6; p = 0.001) not in 'unselected' (HR 1.8; p = 0.1). Increased CBC occurred in non-BRCA1/2 patients mainly before genetic testing, suggesting ascertainment bias. Tumors were < or =T1 in 62% of non-BRCA1/2 versus 50% of sporadic patients (p = 0.003), node-negative in 55% versus 52% respectively (p = 0.5). After correction for stage and therapy, OS did not differ between 'unselected' non-BRCA1/2 and sporadic patients (HR 0.8; p = 0.3), but was improved in late-tested non-BRCA1/2.

CONCLUSION

Overall survival and contralateral breast cancer incidence were similar in 'unselected' non-BRCA1/2- and sporadic patients. Reports of higher CBC incidence and better survival in non-BRCA1/2 patients may substantially be caused by DNA testing selection-bias.

Breast MR imaging in women at high-risk of breast cancer. Is something changing in early breast cancer detection?

In the last few years, several papers have addressed the introduction of contrast-enhanced MR imaging for screening women at high risk for breast cancer. Taking in consideration five prospective studies, on 3,571 screened women with hereditary predisposition to the disease and 9,652 rounds, we found that 168 patients were diagnosed with breast cancer (155 screen-detected, eight interval, and five cancers excluded from analysis) with a detection rate per year of 1.7%. These cancers were small (49% equal to or less than 10 mm in diameter) but aggressive, 82% being invasive and 49% with histologic grade 3; however, only 19% of these invasive cancers were associated with nodal involvement. The pooled sensitivity was 16% for clinical breast examination, 40% for mammography, 43% for ultrasound, and 81% for MR. The positive predictive value (calculated on the basis of the number of invasive diagnostic procedures due to false positives) was 33%, 47%, 18%, and 53%, respectively. Aim of the present article is to present the historical development of MR imaging of breast tumors that made this application theoretically and technically possible, to explain what strategic problems we face in the presence of a hereditary predisposition to the disease, to review the main results of the published studies, and to outline open problems and future perspectives.

Contralateral recurrence and prognostic factors in familial non-BRCA1/2-associated breast cancer

BACKGROUND

A higher incidence of contralateral breast cancer and ipsilateral recurrence has been reported in familial breast cancer than in sporadic cancer. This study investigated the influence of contralateral cancer and tumour stage on survival in patients with familial non-BRCA1/BRCA2-associated breast cancer.

METHODS

The incidences of contralateral breast cancer, ipsilateral recurrence, distant disease-free and overall survival were assessed in 327 patients from families with three or more breast and/or ovarian cancers, but no BRCA1 or BRCA2 gene mutation (familial non-BRCA1/2), and in 327 control subjects with sporadic breast cancer, matched for year and age at detection.

RESULTS

Mean follow-up was 7.3 years for patients with familial-non-BRCA1/2 cancers and 6.5 years for patients with sporadic breast cancer. Tumours were stage T1 or lower in 62.1 per cent of familial non-BRCA1/2 cancers versus 49.9 per cent in sporadic breast cancers (P = 0.003), and node negative in 55.8 versus 52.1 per cent, respectively (P = 0.477). After 10 years the incidence of metachronous contralateral breast cancer was 6.4 per cent for familial non-BRCA1/2 tumours versus 5.4 per cent for sporadic cancers. The rate of ipsilateral recurrence was not significantly increased (17.0 versus 14.2 per cent, respectively, at 10 years; P = 0.132). Tumour size (hazard ratio (HR) 1.02 per mm increase, P = 0.016) and node status (HR 2.6 for three or more involved nodes versus node negative, P = 0.017) were independent predictors of overall survival in the familial non-BRCA1/2 group, and in the whole group, whereas contralateral breast cancer (HR 0.7, P = 0.503) and risk-reducing contralateral mastectomy (HR 0.4, P = 0.163) were not.

CONCLUSION

Stage at detection was a key determinant of prognosis in familial non-BRCA1/2 breast cancer, whereas contralateral cancer was not. Risk-reducing contralateral mastectomy did not significantly improve survival, but early detection can. Decisions on breast-conserving treatment can be made on the same grounds in patients with familial and sporadic breast cancer.

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.

Factors Affecting Sensitivity and Specificity of Screening Mammography and MRI in Women with an Inherited Risk for Breast Cancer

BACKGROUND

The MRISC study is a screening study, in which women with an increased risk of hereditary breast cancer are screened by a yearly mammography and MRI, and half-yearly clinical breast examination. The sensitivity found in this study was 40% for mammography and 71% for MRI and the specificity was 95 and 90%, respectively. In the current subsequent study we investigated whether these results are influenced by age, a BRCA1/2 mutation, menopausal status and breast density.

PATIENTS AND METHODS

From November 1999 to October 2003, 1909 eligible women were screened and 50 breast cancers were detected. For the current analysis, data of 4134 screening rounds and 45 detected breast cancers were used. For both imaging modalities, screening parameters, receiver operating characteristic (ROC) curves and uni- and multivariate odds ratios (ORs) were calculated. All analyses were separately performed for age at entry (< 40, 40-49, > or =50), mutation status, menopausal status and breast density.

RESULTS

Sensitivity of MRI was decreased in women with high breast density (adjusted OR 0.08). False-positive rates of both mammography (OR(adj) 1.67) and MRI (OR(adj) 1.21) were increased by high breast density, that of MRI by pre-menopausal status (OR(adj) 1.70), young age (OR(adj) 1.58 for women 40-49 years versus women > or =50 years) and decreased in BRCA1/2 mutation carriers (OR(adj) 0.74). In all investigated subgroups the discriminating capacity (measured by the area under the ROC-curve) was higher for MRI than for mammography, with the largest differences for BRCA1/2 mutation carriers (0.237), for women between 40 and 49 years (0.227) and for women with a low breast density (0.237).

CONCLUSIONS

This report supports the earlier recommendation that MRI should be a standard screening method for breast cancer in BRCA1/2 mutation carriers.

Role of MRI in screening women at high risk for breast cancer

Breast cancer is diagnosed in over one million women worldwide every year. Until breast cancer can be prevented, early detection offers the best chance for cure. Mammographic screening is an effective method for early detection in average-risk women. However, the sensitivity of mammography is decreased in women at high risk for breast cancer. Because of its high sensitivity, multiple investigators have studied the potential role of MRI in screening women at high risk. In the past few years, results from eight major clinical trials exploring breast MRI as a screening tool have been published. Combined, the studies included 4271 patients and found 144 breast cancers detected by MRI, for an overall cancer yield of 3%. The sensitivity of MRI ranged from 71% to 100% across the studies. Although its reported specificity was variable, the call-back rates and risk of benign biopsies were within acceptable limits. In general, patients who underwent breast MRI screening had a 10% risk of being called back, and a 5% risk of having a benign biopsy. This work reviews the literature and current practices and recommendations for MRI as a screening tool for high-risk women.