Differential diagnosis of breast tumors. The sensitivity graded method of ultrasonotomography and clinical evaluation of its diagnostic accuracy

Differential diagnosis of breast tumors was performed by a sensitivity graded method of two dimensional (B‐scan) ultrasonotomography on 235 cases. The clinical significance of several new differential criteria such as tadpole‐tail sign, lateral shadow sign, bilateral disappearance of distal wall echoes for benign lesions, acoustic middle shadow sign, and complete disappearance of distal limit of tumor echoes for malignant lesions, was evaluated in 67 histologically proven cases. Bio‐acoustic mechanisms for the appearance of such differential points are discussed. Breast cancer was correctly diagnosed in 90% of the cases, the rate for small cancer (less than 2 cm) being 82%. Scirrhous carcinoma, papillary carcinoma, and medullary carcinoma were correctly diagnosed in 100%, 88%, and 81% of the cases respectively, whereas benign lesions such as fibro‐cystic mastopathy, fibroadenoma, and cyst were correctly diagnosed in 100%, 83%, and 100% of the cases respectively.