The impact of mammography on the patterns of patients referred for definitive breast irradiation

Abstract

To evaluate the impact of mammography on the patterns of patients referred for definitive breast irradiation, the records of 1507 cases of carcinoma of the breast in 1468 women treated between 1977 and 1988 with breast-conserving surgery and definitive irradiation were reviewed. All patients had undergone complete excision of the primary tumor with or without axillary staging. All patients had either noninvasive, intraductal carcinoma (American Joint Committee [AJC] Stage Tis, N0) or invasive carcinoma (AJC Stage T1 or T2, N0 or N1). The use of a mammographic needle localization breast biopsy for diagnosis of a nonpalpable carcinoma steadily increased over time from 3% (one of 32) in in 1977-78 to 26% (111/421) in 1987-88 (P less than 0.0001). The percentage of intraductal carcinomas was significantly increased for the cases in which a mammographic needle localization was used for biopsy of a nonpalpable carcinoma (P less than 0.0001). There was an increase in the incidence of intraductal carcinomas in patients referred for definitive breast irradiation over time from 6% (two of 32) in 1977-78 to 13% (53/421) in 1987-88 (P = 0.0004). These results demonstrate that the use of mammography has had a significant impact on the patterns of patients referred for breast conservation and definitive irradiation with an increase in the percentage of nonpalpable cancers diagnosed using mammographic needle localization and with an increase in the percentage of intraductal carcinomas referred over time.