Breast Cancer Mortality among Women with a BRCA1 or BRCA2 Mutation in a Magnetic Resonance Imaging Plus Mammography Screening Program

Abstract

Annual breast magnetic resonance imaging (MRI) plus mammography is the standard of care for screening women with inherited BRCA1/2 mutations. However, long-term breast cancer-related mortality with screening is unknown. Between 1997 and June 2011, 489 previously unaffected BRCA1/2 mutation carriers aged 25 to 65 years were screened with annual MRI plus mammography on our study. Thereafter, participants were eligible to continue MRI screening through the high-risk Ontario Breast Screening Program. In 2019, our data were linked to the Ontario Cancer Registry of Cancer Care Ontario to identify all incident cancers, vital status and causes of death. Observed breast cancer mortality was compared to expected mortality for age-matched women in the general population. There were 91 women diagnosed with breast cancer (72 invasive and 19 ductal carcinoma in situ (DCIS)) with median follow-up 7.4 (range: 0.1 to 19.2) years. Four deaths from breast cancer were observed, compared to 2.0 deaths expected (standardized mortality ratio (SMR) 2.0, p = 0.14). For the 489 women in the study, the probability of not dying of breast cancer at 20 years from the date of the first MRI was 98.2%. Annual screening with MRI plus mammography is a reasonable option for women who decline or defer risk-reducing mastectomy.

Breast cancer incidence and early diagnosis in a family history risk and prevention clinic: 33-year experience in 14,311 women

“…A study of 491 women with a germline BRCA mutation, who were annually screened with MRI and mammography for a median of 12.7 years found incidence breast cancer was 2% annually. There were four breast cancer-related deaths among 91 who developed breast cancer [ 32 ].…”

From the patient to the population: Use of genomics for population screening

“…Among high-risk females, MRI in combination with mammography has been found to be more sensitive than either modality alone ( Warner et al, 2008 ; Mann et al, 2019 ) and to improve overall survival relative to mammography alone ( Bae et al, 2020 ). In an observational cohort study of MRI in combination with mammography among unaffected female BRCA1/2 heterozygotes, the probability of dying of breast cancer within 20 years was 2% ( Warner et al, 2020 ). For ovarian cancer risks, guidelines from the National Comprehensive Cancer Network (NCCN) suggest that transvaginal ultrasound and CA-125 may be offered at the clinician’s discretion to BRCA1/2 carriers who have not elected for risk-reducing salpingo-oophorectomy ( National Comprehensive Cancer Network (NCCN), 2021a ).…”

The risks of cancer in older women with BRCA pathogenic variants: How far have we come?

“…Strategies to significantly reduce the risk of developing cancer in a woman with a BRCA1 or BRCA2 pathogenic variant include preventive surgery (bilateral salpingo‐oophorectomy [BSO] and bilateral risk reducing mastectomy) and chemoprevention (e.g., tamoxifen, raloxifene) 2–6 . The other goal, once cancer develops, is to prevent death from cancer, which may be achieved by early breast cancer detection (e.g., intensified breast screening from age 30 years including magnetic resonance imaging [MRI] and mammography), 7 or by personalized cancer treatment (e.g., platinum‐based chemotherapy and/or poly(adenosine diphosphate ribose) polymerase [PARP]‐inhibitors) 8–10 . Strategies that focus on reducing mortality (e.g., MRI surveillance and treatment) do not necessarily impact on cancer incidence.…”