Janice Sung MD, Presenter: Nothing to Disclose

Punam Bajaj MD, Abstract Co-Author: Nothing to Disclose

Rebecca Elizabeth Alis MD, Abstract Co-Author: Nothing to Disclose

Sandra Brennan MBBCh, MSc, Abstract Co-Author: Nothing to Disclose

D. David Dershaw MD, Abstract Co-Author: Nothing to Disclose

Elizabeth A. Morris MD, Abstract Co-Author: Nothing to Disclose

To assess the utility of MRI as a screening tool for detecting otherwise occult breast cancers in women with a history of biopsy proven lobular carcinoma in situ (LCIS).

This study was IRB approved. Retrospective review of our database identified 737 screening MRIs performed in 237 women with a history of LCIS from 2003 to 2008 over a 5.5 year period. A mean of 3 breast MRIs were performed per patient. Age at the first screening MRI, number of biopsies recommended based on MRI findings, number of cancers diagnosed, and their method of detection were determined.

Mean age at first screening MRI was 52 years (range 27-78). Biopsy was recommended for 67 lesions in 55/237 (23%) patients. 7 lesions not biopsied were followed for a mean of 2.4 years without change. 11/60 (18%) lesions that underwent biopsy were malignant. A total of 16 cancers were diagnosed in 14 patients, including 1 patient with bilateral in situ cancer who later developed an invasive cancer. Of these, 11/16 (69%) were detected only on MRI (10 masslike, 1 nonmasslike) and 5/16 (31%) were detected only on mammography (5 calcifications). Cancer yield per year of screening detected by MRI was 2% and by mammography was 0.9%. Of the 11 MRI detected cancers, 9 were invasive cancers (mean size 0.9 cm, range 0.5-1.3 cm), including 2 with positive axillary nodes, and 2 were DCIS. Of the 5 cancers detected on mammography, 2 were invasive cancers (mean size 0.3 cm, range 0.1-0.4 cm), 1 with positive nodes, and 3 were DCIS.

The addition of MRI to mammography for annual screening of women with a history of LCIS doubled the cancer detection rate. Additional cancers found by MRI were mostly minimal, invasive tumors.

Breast MRI will detect otherwise occult cancers in women with a history of LCIS. Annual screening MRI in conjunction with mammography should be considered to screen this high risk population.

Sung, J, Bajaj, P, Alis, R, Brennan, S, Dershaw, D, Morris, E, Screening Breast MRI in Women with a History of LCIS.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9004476.html