[Mass-screening for breast cancer using C-mode display ultrasonography].

: In order to elevate the detection rate of breast cancer in mass-screening, we examined whether the C-mode display ultrasonography is useful for detection of breast cancer. 1) Diagnostic sensitivity of C-mode ultrasonography was 88.2%, specificity was 66.7% and predictive value was 58.8%, respectively. 2) The detection rate of C0mode ultrasonography was 100% for tumors more than 5.0cm, 87.5% for 2.0-5.0cm, 74.2% for less than 2.0cm. Especially, the diagnostic value of lesser than 1.0cm breast cancer was high, 66.7%. 3) In findings of C-mode ultrasonography, images characteristic of carcinoma can be obtained regarding their unclear margin (70.6%), heterogenous (88.2%) and hypoechoic (70.6%) internal echoes and malignant halo (61.8%). Our present data suggest that C-mode ultrasonography is very useful for the mass screening for breast cancer.