Fifty-one patients with clinically palpable breast cancer were examined using small-parts echotomography. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of overall diagnosis were assessed in the two groups of patients: T1 (diameter less than 2 cm) and T2-T3-T4 (diameter greater than 2 cm). The frequency of the main echographic signs associated with breast cancer was also investigated. Diagnostic accuracy was found to be high in the T2-T3-T4 group (93%), but very low in the T1 group (71%). The study confirms the importance of ultrasound as an additional test in the study of breast cancer. However, this method becomes increasingly less sensitive and specific as the size of the tumour decreases.