Report of the Working Groups on Breast MRI: Report of the High-Risk Screening Group

Abstract

Key Words: high risk, screening S ignificant advances have been made in identifying women at high risk for developing breast cancer. The most notable is the discovery of the BRCA-1 and BRCA-2 genes. For women carrying the BRCA mutations, approximately 80% have developed the disease by age 70 years (1,2). However, to date, it appears that a minority of breast cancers occur in women with known mutations and that, in fact, women at increased risk for breast cancer comprise a diverse population. Because genetic testing is only available for the known mutations ( BRCA-1 and 2 ), the majority of the actual hereditary breast cancers seemingly occur in "mutation-negative" patients. For the same reason, a negative mutational analysis cannot be used to rule out familial breast cancer. Instead, personal and family history are used for risk assessment.In addition to the actual "hereditary" breast cancers, where a single malfunctioning tumor suppressor gene facilitates breast cancer genesis secondary to a mutation of a single gene locus, it is well known that a strong family history of breast cancer increases the risk for developing nonhereditary, sporadic breast cancer. In fact, family history has long been identified as the major risk factor for developing sporadic breast cancer. It is hypothesized that cancer genesis in sporadic breast cancer is mediated by a multifactorial process that includes several different genes. Thus women with no known mutations but with strong family histories are known to be at increased risk for breast cancer. For example, women with two firstdegree relatives with breast cancer have a more than fourfold increased risk compared to women with no family history (3).Women with a personal history of breast cancer are at increased risk. These women have a two-to sixfold increased risk of developing breast cancer in the contralateral breast than women in the general population have of developing a first breast cancer (4 -6). In addition, women with a history of therapeutic chest radiation have a significantly increased risk of developing breast cancer. Breast cancers have been reported at relatively high rates in women treated with radiation for Hodgkin's disease as early as 10 years after treatment (7).We know how to identify many of these women at high risk, but we have not known how best to care for them. In 1996 a task force was convened by the Cancer Genetics Studies Consortium, sponsored by the National Human Genome Research Institute, in order to identify appropriate recommendations for individuals found to have an inherited predisposition to cancer. After careful review of the relevant published literature, the task force published the following provisional guidelines for BRCA-1 and BRCA-2 mutation carriers and for those with a family history compatible with hereditary breast cancer: monthly breast self-examinations beginning at age 18 to 21 years, annual or semiannual clinical breast examinations, and annual mammography beginning between age 25 and 35 years (8). The task force cautioned that ...

Detecting Breast Cancer with Non-contrast MR Imaging: Combining Diffusion-weighted and STIR Imaging

“…As research on high-risk breast cancers has progressed, gene mutation and family and patient history of breast cancer have been accepted as risk factors. 1,2 Several reports show that about 80z of women with BRCA-1 and BRCA-2 gene mutations developed breast cancers by age 70. [2][3][4] It is accepted that a patient with a strong family history has a greater risk for developing nonhereditary, sporadic breast cancer as well as so-called``hereditary'' breast cancer.…”

“…1,2 Several reports show that about 80z of women with BRCA-1 and BRCA-2 gene mutations developed breast cancers by age 70. [2][3][4] It is accepted that a patient with a strong family history has a greater risk for developing nonhereditary, sporadic breast cancer as well as so-called``hereditary'' breast cancer. [2][3][4][5] For a patient with a personal history of breast cancer, the probability of developing cancer in the contralateral breast is reported to be 2 to 6 times higher than that of a patient without such history.…”

PPV3 of Suspicious Breast MRI Findings

“…B reast magnetic resonance imaging (MRI) is a highly sensitive imaging tool in the detection and characterization of breast cancer (1)(2)(3)(4)(5)(6)(7)(8)(9). MRI is useful in the evaluation of women with a new diagnosis of breast cancer to determine the extent of disease and screen the contralateral breast when there is a new diagnosis (9)(10)(11)(12).…”

“…As a result, the recommendation for biopsy of a suspicious lesion may yield cancer in a lesser percentage of patients than when mammograms or US are used to diagnose cancer. Therefore, suspicious MRI findings would be expected to have a decreased positive predictive value (PPV 3 ) when compared to the PPV for suspicious findings identified on mammography and US.…”

“…Our primary objectives were to evaluate suspicious MRI findings and determine whether MRI imaging characteristics, method of biopsy, ability to visualize the finding on second-look imaging modality, and the patient's clinical history affected the PPV 3 .…”