Spectrum of Mammographically Detected Breast Cancers

Abstract

Mammographic screening of women at both ends of the age spectrum presents a number of challenges. The purpose of this study was to characterize experience with mammographic detection of breast cancer. The two goals were 1) to establish the cancer detection rate of screening mammography and 2) to compare the tumor size of cancers found by mammography, physical examination, or both modalities. From January 1994 through June 1997, data on 609 consecutive female primary breast cancer patients were collected concurrent with definitive surgical therapy. The method of detection was determined by the surgeon, after reviewing mammogram and physical examination. Screening ultrasound was not used. For the 184 patients under 50 years of age, 53 (29%) cancers were detected by mammography only and 48 (26%) by physical examination only. Women under 50 years of age had fewer cancers detected by mammography only (P < 0.001) and more cancers detected by physical examination only (P = 0.0014) than those over 50. With increasing age, the proportion of women with ductal carcinoma in situ decreased (P = 0.004), and the proportion with T_1c or T₂ tumors increased (P = 0.006). We conclude that 1) when examining women under 50 years of age, the surgeon must be clearly focused on the double-edged sword of screening mammography in this age group, and 2) community cancer programs should encourage annual screening of women over 40 years of age but focus on those over 70, without an arbitrary upper age limit.