Leiden University Scholarly Publications

Rijnsburger, A.J.; Obdeijn, I.M.; Kaas, R.; Tilanus-Linthorst, M.M.A.; Boetes, C.; Loo, C.E.; ... ; Klijn, J.G.M. 2010

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

Article / Letter to editor

metadata only

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... Show morePurpose 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. Show less