Does the proven benefit of mammography extend to breast cancer patients over age 70?

Background. Prospective randomized studies show reduced breast cancer mortality among women offered mammographic screening; yet, few women 70 or older were represented in these trials. We examine the impact of mammography on stage at diagnosis of breast cancer, over the years when mammography came into general use, comparing women aged 40 to 69 with those aged 70 and older. Methods. We reviewed the records of 1,001 consecutive patients 40 and older treated for invasive or in situ breast cancer in the surgical practice of one of us (H.S.C.) between 1979 and 1993, comparing trends in mammography use, means of diagnosis, tumor size, axillary node status, and pathology. Results. The proportion of cases diagnosed by mammography increased over time To a comparable degree in both age groups, as did the proportion of T1 and DCIS or microinvasive cancers. This trend toward earlier stage appears entirely due to an increasing use of mammography. Conclusion. The potential benefit of regular mammography to healthy women aged 70 and older may equal that observed in their younger counterparts.