Continuous ultrasound B-scanning of palpable breast masses.

Of 210 pathologically confirmed palpable breast masses examined by continuous ultrasound B-scanning using a 2.5- or 7-MHz transducer and mammography, fluid filled cysts more than 1 cm in diameter were diagnosed accurately in 75 cases. Of the 103 solid masses studied by echography, 31 were circumscribed (29 benign fibroadenomas and 2 circumscribed medullary carcinomas) and 72 were not. Infiltrating carcinoma represented the majority of the latter type, although 2 cases of chronic inflammation had the same echographic appearance. Thirty palpable breast masses less than 2 cm in diameter were not delineated with the 2.5-MHz transducer, and biopsy showed benign disease. The combiantion of mammography and continuous ultrasound B-scanning of palpable breast masses improved the diagnostic accuracy obtained with mammography alone and aided in the differentiation of nondiagnostic mammograms.