[Bilateral malignancy of the breast].

The breast cancer is the most common malignant disease in women, and makes 26 percent of all malignant diseases in women. Bilateral breast cancer is very rare, especially simultaneous one. We analyzed 420 operated breast cancers in Surgical Clinic in Split within five years period. There were 8 patients with simultaneous or metachronous bilateral breast cancer. Their incidence, difficulties in diagnostics and treatment, pathologic findings and prognosis are discussed. It is justifiable to follow the contralateral breast of patients with the breast cancer.