OBJECTIVE To evaluate the use of spiral CT in the diagnosis of breast lesions. METHODS 93 female patients with suspicious or uncertain mammographic findings were examined by CT before and after contrast enhancement according to the following practical method: table movement, 6 mm/s, slice thickness 6 mm, increment 4 mm, contrast 200 ml, injection rate 3 ml/s, scan start 50 s after the beginning of the injection. Histological confirmation was present in 85 patients. RESULTS All 44 invasive carcinomas were recognised. They were characterised by intensive focal contrast uptake. Only 2 out of 7 intraductal carcinomas were not shown by CT. 36 out of 38 benign lesions were correctly diagnosed. 2 out of 11 fibroadenomas showed strong enhancement and were incorrectly diagnosed. The examinations provided valuable additional information compared to mammography and sonography. CONCLUSIONS Spiral CT is very useful for elucidating problems in the diagnosis of breast lesions. Its advantages consist in the speed of the method, comfort for the patient, absence of movement artifacts, easy standardisation and wide applicability.