Annual screening mammography for breast cancer in women 75 years old or older: to screen or not to screen

Abstract

Objective: The purpose of the study was to review screening mammography examinations at our institution from 2007 through 2013 with the primary endpoint of determining the incidence of breast cancer and the associated histologic and prognostic features in women 75 years old or older.

Materials and methods: Patients who presented for screening mammography who ultimately received a BI-RADS assessment of category 4 or 5 for a suspicious abnormality were followed retrospectively through completion of care and were analyzed with respect to pathology results, treatment, and family history.

Results: From 2007 through 2013, 68,694 screening mammography examinations were performed. Of these screening examinations, 4424 (6.4%) were performed of patients 75 years old or older. On the basis of these examinations, 64 biopsies were recommended. Sixty biopsies were performed, and these biopsies detected 26 breast cancers. These results correspond to a breast cancer detection rate of 5.9 per 1000 screening examinations and a positive predictive value 2 (PPV2), defined as the probability of breast cancer after a BI-RADS assessment category of 4 (suspicious abnormality) or 5 (highly suggestive of malignancy), of 40.6%. Approximately 85% (22/26) of the screening-detected cancers in the women in this age group were invasive. For those with known genetic status (18 of 26), 33% had a first-degree relative with breast cancer.

Conclusion: Although women 75 years or older accounted for less than 10% of the total screening population during the study time period, the breast cancer detection rate in this cohort was 5.9 per 1000 screening examinations, which is compatible with the American College of Radiology's recommendations, and most of these breast cancers were invasive. These results are relevant when considering appropriate age ranges for annual screening mammography.

Keywords: U.S. Preventive Services Task Force (USPSTF) guidelines; breast cancer; older women; screening mammography.