The ES DBT (Breast Tumor Diagnosis) expert system is designed for early diagnosis of breast tumors. It uses basic diagnostic methods: thermography, medical history, physical examination, and echotomography. It predicts the percentage of development of the following tumors: breast cancer, lipoma, fibroadenoma, diffuse fibrocystic mastopathy, localized fibrocystic mastopathy, cyst, diffuse fibrocystic mastopathy, local fibrocystic mastopathy, mastitis.