Abstract GS4-07: Costs and effects in the first randomized trial comparing MRI breast cancer screening with mammography in women with a familial risk: FaMRIsc

Background: The large favorable stage shift, that MRI screening causes as compared with mammography has been published recently in Lancet Oncology as well as the disadvantage of more false-positive results with MRI. Here we want to present the first results of cost and effectiveness. Methods: In twelve Dutch hospitals, 1355 women aged 30-55 years with a cumulative lifetime risk (CLTR) of ≥20% without a BRCA1/2 mutation were randomized into two groups. From January 2011 until December 2017, women in the MRI-group received yearly MRI-screening, clinical breast examination (CBE), and mammography every other year; and in the Mx-group yearly mammography and CBE. We here present cost per group as well as per detected cancer in both groups, also by age group and breast density. Cost per life year gained can be presented in December. Results: After on average 4.3 screening rounds per woman, in the MRI-group (N=674) compared to the Mx-group (N=680) more breast cancers were detected (40 versus 15, p<0.002), invasive cancers were smaller (median size 9 versus 17 mm, p=0.01) and less often node positive (17% versus 63%, p=0.023) (Table). This resulted in lower cost for detection and treatment per tumor in the MRI-group compared to the Mx-group and lower mean treatment costs (MRI-group: €6,736; Mx-group: €10,128). In incident rounds fewer large or node positive cancers were detected with MRI, reducing the cost for adjuvant therapy, but there remained more false positive results and biopsies with MRI, increasing the cost for additional investigations. The total cost of MRI screening was nearly twice as high as for mammography-screening. Per detected cancer MRI screening was cheaper than mammography, especially above 50 yrs. and at density A-C (see Table). Cost per life year gained will be discussed. Conclusions MRI-screening advances the detection of breast cancer greatly, but with more additional investigastions. MRI-screening may be cost-effective in groups with sufficient tumor incidence, like women with familial risk.

This study was supported by funds of: the Dutch Governement ZonMw grant no. 200320002, The Dutch Cancer Society (DDHK 2009-4491), A Sisters Hope, Pink Ribbon, Stichting Coolsingel, J&T Rijke Stichting.

Table 1. Characteristics of participating women, detected breast cancers, and cost according to study armParticipantsMRI-arm n=674Mx-arm n=680p-valueMean age - yr ± SD44.7 ± 6.344.7 ± 6.3Premenopausal512 (76%)505 (74%)BI-RADS density categorya A(entirely fat) B (scattered densities) C (heterogeneously dense) D (extremely dense)88 (13%) 248 (37%) 237 (35%) 98 (15%)92 (14%) 229 (34%) 243 (36%) 102 (15%)Mean age at cancer detection49,6 ± 7.150,8 ± 4,60.88No cancer - no. (%) Invasive breast cancers - no. (%) DCIS - no. (%)634 (94%) 24 (4%) 16 (2%)666 (98%) 8 (1%) 7 (1%)0.0017Median size of invasive cancers9 mm (5-14)17 mm (13-22)0.01Node positive4/24 (17%)5/8 (63%)0.023Biopsy nr.14954< 0.0001Total screening cost in FaMRIsc€ 1,094,241€ 516,440Cost per detected cancer€ 32,340€ 42,384Cost per detected ca. BIRADS A-C€ 28,945€ 39,964aDetermined by radiologists, according to the fourth ACR BI-RADS edition

Citation Format: Madeleine MA Tilanus-Linthorst, H Amarens Geuzinge, Inge-Marie M Obdeijn, Emiel JT Rutgers, Ritse M Mann, Sepideh Saadatmand, Diderick BW de Roy van Zuidewijn, Robert AEM Tollenaar, Marc BI Lobbes, Margreet GEM Ausems, Martijne van 't Riet, Maartje J Hooning, Jelle Wesseling, Ingeborg Mares-Engelberts, Ernest JT Luiten, Jan C Oosterwijk, Eveline AM Heijnsdijk, Harry J de Koning. Costs and effects in the first randomized trial comparing MRI breast cancer screening with mammography in women with a familial risk: FaMRIsc [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS4-07.