Breast Cancer Screening With Addition of MRI to Mammography in Women With Familial Risk
The Dutch FaMRIsc study, reported in The Lancet Oncology by Saadatmand et al, found that the addition of screening magnetic resonance imaging (MRI) to mammography resulted in identification of more breast cancers—and identification at an earlier stage—vs mammography alone among women with a familial risk of disease without causative hereditary gene mutations.
In the study, 1,355 women with a familial risk of breast cancer from 12 sites in the Netherlands were randomly assigned between January 2011 and December 2017 to undergo annual MRI and clinical breast examination plus biennial mammography (MRI group, n = 675) or annual mammography and clinical breast examination (mammography group, n = 680). Women were aged 30 to 55 years and had a cumulative lifetime breast cancer risk ≥ 20% due to familial predisposition but were wild-type for BRCA1, BRCA2, and TP53.
Primary outcomes were number, size, and nodal status of detected breast cancers.
Screening Outcomes
The mean number of screening rounds per woman was 4.3. A total of 40 breast cancers were detected in the MRI group vs 15 in the mammography group (P = .0017). Of 24 invasive cancers detected in the MRI group vs 8 in the mammography group, those in the MRI group were smaller (median size = 9 mm vs 17 mm, P = .010) and less frequently node-positive (n = 4 [17%] vs 5 [63%], P = .023).
Stages of cancers detected at incident rounds were earlier in the MRI group: 12 (48%) of 25 in the MRI group vs 1 (7%) of 15 in the mammography group were stage T1a and T1b; 1 (4%) of 25 in the MRI group and 2 (13%) of 15 in the mammography group were stage T2 or higher (P = .035); and 2 (11%) of 18 in the MRI group vs 5 (63%) of 8 in the mammography group were node-positive. The total of seven tumors detected at stage T2 or higher were in the two highest breast density categories (P = .0077).
The investigators concluded, “MRI screening detected cancers at an earlier stage than mammography. The lower number of late-stage cancers identified in incident rounds might reduce the use of adjuvant chemotherapy and decrease breast cancer–related mortality. However, the advantages of the MRI screening approach might be at the cost of more false-positive results, especially at high breast density.”
Madeleine M.A. Tilanus-Linthorst, MD, of the Department of Surgery, Erasmus University Medical Center, Rotterdam, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funded by the Dutch Government ZonMw, Dutch Cancer Society, A Sister’s Hope, Pink Ribbon, Stichting Coolsingel, and J&T Rijke Stichting. For full disclosures of the study authors, visit thelancet.com.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
