Manhtab Vasigh - Breast Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran
Ahmad Kaviani - Department of Surgery, Tehran University of Medical Science, Tehran, Iran
Abdolali Assarian - Department of Research, Kaviani Breast Diseases Institute (KBDI), Tehran, Iran
Faina Nakhlis - Department of Surgery, Brigham and Women's Hospital, Boston, USA

Background: Women with atypical hyperplasia are about ۴ times more likely todevelop breast cancer compared with the general population. Atypical hyperplasiahas been recommended to be used as a criterion for the inclusion of women inchemoprevention programs. Chemoprevention offers promise as a strategy forreducing the incidence of breast cancer in high-risk population.Methods: A literature search was conducted in PubMed and Scopus databasesusing the search terms “breast atypia,” “chemoprevention,” and “risk-reducingtherapy” for papers published from ۱۹۶۶ to Aug ۲۰۱۷. The search was limited toEnglish-language papers and human studies. It yielded ۱۱۴ search items. Articleselection for possible inclusion was performed using the title and abstract. Finally,۱۲ studies were identified as eligible for inclusion in the review.Results: The rates of atypical ductal hyperplasia (ADH) ranged from a low of ۲per ۱۰۰۰۰ mammograms in ۱۹۹۵ to a high of ۶ per ۱۰۰۰۰ mammograms in ۲۰۱۱.Lobular neoplasia was an incidental finding in ۰.۵%–۳.۵% of core biopsies. Trueincidence of lobular neoplasia is unknown. Women with atypical breast lesions havea ۵%–۱۱% risk of developing breast cancer within ۵ years and a ۱۷%–۲۶% risk ofdeveloping breast cancer within ۱۰ years. The reported risk of breast cancer withatypical hyperplasia (ADH and ALH are often grouped together) is approximately۱۹% within ۱۵ years. It is believed that the initiation of chemoprevention would beappropriate; if the ۱۰-year breast cancer risk is ۴% to ۸%. Breast cancer riskreduction by chemoprevention is reported to be ۳۲% to ۵۵% in breast atypia.Conclusion: According to our findings, patients with a diagnosis of ADH, ALH,or severe ADH should be considered for chemoprevention if they are at least ۳۵years of age and have no contraindications to treatment. Only ۴%–۲۰% of high-riskwomen decide to take chemoprevention, on average.

Atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), breast atypia, chemoprevention, risk reduction