We describe a case of two simultaneous malignancies--anaplastic gastric carcinoma with pleural metastases and left breast carcinoma. These malignancies were recognized in 78-year old woman after right mastectomy performed 30 years ago. Additionaly, during diagnostic procedures rectal polypus found during colonoscopy occurred to be adenoma tubulovillosum. Her parents died from malignancies--mother from gastric cancer and father from pulmonary carcinoma. One should remember that there is always possibility of simultaneous development of more than one primary malignancies in one patient and neoplastic disease is an important cancer risk factor. This observation confirms the important role of genetic factors in the pathogenesis of malignant diseases.