Screening with magnetic resonance imaging and mammography of a UK population at high familial risk of breast cancer: a prospective multicentre cohort study (MARIBS).
BACKGROUND
Women genetically predisposed to breast cancer often develop the disease at a young age when dense breast tissue reduces the sensitivity of X-ray mammography. Our aim was, therefore, to compare contrast enhanced magnetic resonance imaging (CE MRI) with mammography for screening.


METHODS
We did a prospective multicentre cohort study in 649 women aged 35-49 years with a strong family history of breast cancer or a high probability of a BRCA1, BRCA2, or TP53 mutation. We recruited participants from 22 centres in the UK, and offered the women annual screening with CE MRI and mammography for 2-7 years.


RESULTS
We diagnosed 35 cancers in the 649 women screened with both mammography and CE MRI (1881 screens): 19 by CE MRI only, six by mammography only, and eight by both, with two interval cases. Sensitivity was significantly higher for CE MRI (77%, 95% CI 60-90) than for mammography (40%, 24-58; p=0.01), and was 94% (81-99) when both methods were used. Specificity was 93% (92-95) for mammography, 81% (80-83) for CE MRI (p<0.0001), and 77% (75-79) with both methods. The difference between CE MRI and mammography sensitivities was particularly pronounced in BRCA1 carriers (13 cancers; 92%vs 23%, p=0.004).


CONCLUSIONS
Our findings indicate that CE MRI is more sensitive than mammography for cancer detection. Specificity for both procedures was acceptable. Despite a high proportion of grade 3 cancers, tumours were small and few women were node positive. Annual screening, combining CE MRI and mammography, would detect most tumours in this risk group.
Leach
M O
MO
MARIBS Study Office, Section of Magnetic Resonance, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey SM2 5PT, UK. martin.leach@icr.ac.uk
Boggis
C R M
CR
Dixon
A K
AK
Easton
D F
DF
Eeles
R A
RA
Evans
D G R
DG
Gilbert
F J
FJ
Griebsch
I
I
Hoff
R J C
RJ
Kessar
P
P
Lakhani
S R
SR
Moss
S M
SM
Nerurkar
A
A
Padhani
A R
AR
Pointon
L J
LJ
Thompson
D
D
Warren
R M L
RM
D000328:Adult; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000175:diagnosis / Q000235:genetics; D015331:Cohort Studies; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D016158:Genes, p53; D020022:Genetic Predisposition to Disease; D006801:Humans; D008279:Magnetic Resonance Imaging; D008327:Mammography; D008875:Middle Aged; D009154:Mutation; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity
D003287:Contrast Media; D019786:Gadolinium DTPA