Results of breast conserving therapy for early breast cancer and the role of mammographic follow-up.

Abstract

The following article is a review of 23 years of breast-conserving therapy in our hospital. This study was performed to assess and improve the follow-up care of women with early breast cancer and to evaluate whether or not biannual mammogram is useful. Between 1972 and December 1995, 3072 women with pathological size pT1 and pT2 breast cancer were treated with conservative surgery and radiation therapy. Eighty-five patients developed a recurrence in the treated breast as the first site of failure, 12 of which had positive axillary nodes. In the following patient study, those with an noninvasive recurrence were excluded. A retrospective assessment of the entire mammographic course was made, starting with the mammogram at the time of original diagnosis to the mammogram of the recurrence. In our study group the probability for local failure ranged from 1 to 2% per year. At 5 and 10 years the actuarial rates were 5 and 10%. The median time to recurrence was 41 months (range 8-161). Twenty-six (31%) recurrences were detected by mammography alone, 10 (12%) by clinical examination only, and 35 (41%) by both methods. For the patients with an ipsilateral recurrence, the overall actuarial 5- and 10-year survival after treatment was 87 and 70%, respectively. The 5-year actuarial rate of survival from salvage mastectomy was 61%. Considering the high percentage of recurrences detectable by mammography and the possibility of detection within a short-term interval, we think biannual mammographic follow-up is appropriate for the first years following breast-conserving therapy.