[Sonographic diagnosis of breast carcinoma by a 7.5 MHz high-resolution electronic linear array transducer]

The diagnostic quality with 7.5 MHz real-time, transducer was evaluated in 175 cases of breast lesions including 106 carcinoma. All cases were histologically confirmed by surgery or excisional biopsy. In the prospective study, accuracy in carcinoma was 84.6% with true positive ratio of 86.8%. There were 14 false negative cases with carcinoma and 13 false positive cases. Five "early" breast carcinoma within 1 cm in diameter were misdiagnosed as benign breast lesions. The false positive cases were composed of 7 degenerated fibroadenomas, 2 mastopathies and 4 inflammatory changes. In the retrospective study, accuracy in carcinoma was 83.4% with true positive ratio of 93.4%. Compared with the prospective study, false negative cases decreased and false positive cases increased in retrospect. The predictive value of positive results with carcinoma were about 80% in each malignant findings on the criterion of breast carcinoma. The 7.5 MHz electronic, linear-array transducer has several advantages over the 7.5 MHz polymer transducer in detection and also precise observation of the breast lesions.