UICC World Cancer Congress 2006

Objective: To (a) determine the performance of screening mammography, ultrasonography, and physical examination; (b) analyze the influence of age, hormonal status, and breast density; (c) compare the size and stage of tumors detected with each modality; and (d) determine which modality or combination of modalities optimize cancer detection.

Methods: A total of 904 asymptomatic women underwent 2,226 screening sessions, (mammography and physical examination). Women with dense breasts subsequently underwent screening ultrasound. Abnormalities were deemed positive if biopsy findings revealed malignancy and negative if findings from biopsy or all screening examinations were negative.

Results: In 18 women, 22 cancers were found. Sensitivity, specificity, negative and positive predictive values, and accuracy of mammography were 76.6%, 98.7%, 99.6%, 35.5%, and 98.3%, respectively; those of physical examination, 27.2%, 99.2%, 99.2%, 28.7%, and 98.6%, respectively; and those of ultrasound, 75.2%, 96.6%, 99.6%, 20.2%, and 96.5%, respectively. Screening breast ultrasound increased the number of women diagnosed with nonpalpable invasive cancers by 33% (2 of 6). Mammographic sensitivity declined significantly with increasing breast density (P<0.01) (48% for the densest breasts) and in younger women with dense breasts (P =0.03); the effects were independent. Mammography and ultrasound together had significantly higher sensitivity (97%) than did mammography and physical examination together (74%) (P<0.001). Tumors detected at mammography and/or ultrasound were significantly smaller (P=0.01) and of lower stage (P=0.01) than those detected at physical examination. Hormonal status has no significant effect on effectiveness of screening independent of breast density.