Value of Contralateral Surveillance Mammography for Primary Breast Cancer Follow‐up

Mammographic screening of the contralateral breast is often advocated during follow‐up of women previously treated for primary operable breast cancer. The purpose of this study was to determine the value of this investigation. Between 1987 and 1995 a total of 5102 contralateral screening mammograms were performed biennially on 2511 women aged ≤ 70 years following treatment for primary operable breast cancer. Sixty‐five metachronous contralateral breast cancers were identified: 21 (32%) at routine clinical examination, 24 (37%) at mammography, and 20 (31%) by patients between routine follow‐up appointments. The prognostic features of metachronous cancers were better or similar to those of the first cancer in 59 of 65 (91%) cases. Because of the favorable prognostic characteristics of the contralateral cancer, mammographic screening may have contributed to the long‐term survival of 16 of 26 women in whom the histologic characteristics of the first cancer predicted a good prognosis. The cancer detection rate with mammography for these women was 6.5 per 1000 contralateral mammogram investigations at a cost of £3852 per cancer detected. The results of this study suggest that surveillance mammography of the contralateral breast is of value in women whose first cancer predicted a favorable prognosis.