The article discusses the relationship between etiology and risk factors of fibrocystic disease (FCD) and breast cancer (BC), pathogenesis of FCD in connection with increasing risk of BC, assessment of BC risk in patients with FCD; pathogenetic treatment of FCD aimed for preventing BC; the use of the drug progestogel for the treatment of FCD and prevention of BC. FCD and BC have general etiology and the most risk factors are identical for the both pathologies. Multiple risk factors disturb hormonal balance in the organism of a woman, cause hyperestrogenism and epithelium hyperproliferation in the mammary tissue that results in the development of FCD and at presenceof congenital or acquired gene damage results in the development of BC. Decision value for the estimation of degree of a BC risk in patients with FCD has morphological research of mammary tissue got at a biopsy. The risk of developing BC for non-proliferative FCD does not rise or is minimal. Proliferative FCD without atypia or with atypia was associated with significantly increased BC risk in 2 or 4 times, correspondingly. The risk of developing BC for FCD with ductal or lobular carcinoma in situ is maximal and may be increased in 12 times. Progestogel is hormonal medicinal drug containing progesterone for local application. Results of undertaken studies and supervisions allow to conclude that progestogel is not only effective and safe drug for pathogenetic treatment of FCD and thus could be regarded as indirect factor to decrease BC risk.