Since fine needle localization biopsy has been introduced, surgeons can have performed biopsies for nonpalpable microcalcified breast lesions, but there are many controversies in determining the disease characteristics and guideline for biopsy with only the findings on mammography. This study was designed to determine the breast cancers according to microcalcification types.

We reviewed 91 cases with only microcalcifications on mammography and with performing localization biopsies from January 1995 to June 1998 at department of surgery, Korea University Hospitals. We subdivided the type of microcalcifications into casting-type, crushed stone like-type and amorphous-type.

The mean age was 49 years old (25-82 years). 16 patients (17.6%) among the 91 patients were diagnosed as the breast cancer. Four (22.2%) of 18 patients with casting type, eight (21.6%) of 37 patients with crushed stone-like type, and four (11.1%) of 36 patients with amorphous type microcalcifications were detected in the breast cancer. The incidence of breast cancers by mammographic microcalcificated breast lesions was more prevalent in casting and crushed stone-like types than amorphous types. The mean size of the benign and malignant lesions was 13.11±10.89mm, 13.13±9.51mm, and there was no difference in the size of microcalcifiations between benign and malignant lesions.

Patients who have had clustered microcalcifications of more than 5 within 1 cm circle in diameter on mammography should be undergone biopsies especially in case of casting or crushed stone-like type to detect early breast cancers.