Should we screen BRCA1 mutation carriers only with MRI? A multicenter study

Abstract

BRCA1 mutation carriers are offered screening with MRI and mammography. Aim of the study was to investigate the additional value of digital mammography over MRI screening. BRCA1 mutation carriers, who developed breast cancer since the introduction of digital mammography between January 2003 and March 2013, were included. The images and reports were reviewed in order to assess whether the breast cancers were screen-detected or interval cancers and whether they were visible on mammography and MRI, using the breast imaging and data system classification allocated at the time of diagnosis. In 93 BRCA1 mutation carriers who underwent screening with MRI and mammography, 82 invasive breast cancers and 12 ductal carcinomas in situ (DCIS) were found. Screening sensitivity was 95.7 % (90/94). MRI detected 88 of 94 breast cancers (sensitivity 93.6 %), and mammography detected 48 breast cancers (sensitivity 51.1 %) (two-sided p < 0.001). Forty-two malignancies were detected only by MRI (42/94 = 44.7 %). Two DCIS were detected only with mammography (2/94 = 2.1 %) concerning a grade 3 in a 50-year-old patient and a grade 2 in a 67-year-old patient. Four interval cancers occurred (4/94 = 4.3 %), all grade 3 triple negative invasive ductal carcinomas. In conclusion, digital mammography added only 2 % to the breast cancer detection in BRCA1 patients. There was no benefit of additional mammography in women below age 40. Given the potential risk of radiation-induced breast cancer in young mutation carriers, we propose to screen BRCA1 mutation carriers yearly with MRI from age 25 onwards and to start with mammographic screening not earlier than age 40.

Intensified Surveillance for Early Detection of Breast Cancer in High-Risk Patients

“…Interestingly, the share of triple-negative tumors seems to decrease with age for BRCA1 carriers, but to increase with age for BRCA2 carriers [60]. BRCA1-associated TNBCs often lack typical mammographic features of malignancy, such as spiculated margins or microcalcifications, and are therefore more often occult on mammography [62,63,64,65], decreasing the importance of mammography for the surveillance of BRCA1-positive patients [66] (fig. 1).…”

“…However, intensified surveillance appears to be somewhat less effective in BRCA1 mutation carriers [6], in whom more advanced stage cancers, symptomatic interval cancers as well as breast cancer deaths have been observed despite regular screening with MRI in several of the high-risk surveillance observational studies [61,66,73,78,79]. In the analysis of Heijnsdijk et al [61], which combined data from the Dutch, Canadian and UK high-risk screening trials, the share of T1c and T2+ tumors was 29% and 22%, respectively, for BRCA1 mutation carriers, compared to 16% and 4% for BRCA2 mutation carriers.…”

Relevance and efficacy of breast cancer screening inBRCA1andBRCA2mutation carriers above 60 years: A national cohort study

“…Finally, since so few BRCA1/2 mutation carriers were screened with MRI, no comparative analyses were performed for this group to guarantee statistical accurateness. Screening with additional MRI in younger BRCA1 and BRCA2 mutation carriers is generally considered both effective, sensitivity of at least 70%, 17,34 as well as cost-effective. 35 The preferred method of breast cancer screening for BRCA1/2 mutation carriers !60; MRI and/or mammography, remains to be assessed.…”

Strukturiertes Mammakarzinom-Früherkennungsprogramm

“…Auch bei gleichzeitiger Durchführung einer MRT und einer Mammasonographie werden manche, insbesondere mikrokalkassoziierte Karzinome nur in der Mammographie entdeckt, die Zahl solcher, nur in der Mammographie entdeckten Karzinome ist jedoch insgesamt sehr gering (weniger als 5% aller entdeckten Primärkarzinome; [10,11,24,25] …”