Abstract P3-12-13: Breast atypical hyperplasia and guideline compliance

Background: Atypical hyperplasia of the breast is a high-risk benign lesion that is found in approximately 10% of benign breast biopsies [1] and confers a risk for future breast cancer [2] . The American Society of Clinical Oncology guideline states that pharmacologic risk reduction with the use of a selective estrogen receptor modulator or an aromatase inhibitor should be discussed with women with a 5-year projected absolute risk of breast cancer of 1.7% or higher [3] . The NCCN guideline for risk reduction recommends consideration of risk-reduction interventions, including the use of pharmacologic agents in women with a 5-year risk of 1.7% or higher and a life expectancy of 10 years or longer [4] .The majority of women with atypical hyperplasia meet this risk criterion with their cumulative risk of approximately 1% per year. Method: We retrospectively reviewed excisional biopsy pathology reports between January 2016 and June 2016 with the diagnosis of atypical ductal or lobular hyperplasia to identify patients with pure atypical hyperplasia. Medical records of these patients were then reviewed to identify the percentage of patients referred to a medical oncologist for chemoprevention discussion and the percentage of patients who received chemoprevention following excisional biopsy. Results: Two hundred seventy six patients with the diagnosis of atypical ductal or lobular hyperplasia were identified. Two hundred and sixteen patients were excluded from the analysis due to the presence of other histologies such as carcinoma in situ and invasive carcinoma. Medical records of the remaining sixty patients with pure atypical hyperplasia were reviewed. Eighteen patients9 charts were unavailable for review. All of the remaining forty two patients had a 5-year breast cancer risk of 1.7% or higher. Five of these patients (8.3%) were referred to a medical oncologist for chemoprevention discussion. Two of these five patients (2.3%) received chemoprevention with tamoxifen. For patients who were not referred to medical oncologist, there was one documented discussion of chemoprevention with patient by her surgical oncologist. One patient underwent prophylactic bilateral mastectomies, and therefore, chemoprevention was not recommended. Conclusion: Multidisciplinary strategies need to be implemented to bridge the gap between guidelines and clinical practices which may lead to improved patient outcomes. References: 1. 1. Simpson JF. Update on atypical epithelial hyperplasia and ductal carcinoma in situ. Pathology 2009;41:36-39. 2. 2. Hartmann LC, Sellers TA, Frost MH, et al. Benign breast disease and the risk of breast cancer. N Engl J Med 2005;353:229-237. 3. Visvanathan K, Hurley P, Bantug E, et al. Use of pharmacologic interventions for breast cancer risk reduction: American Society of Clinical Oncology clinical practice guideline. J Clin Oncol 2013;31:2942-2962. J Clin Oncol 2013;31:4383. Citation Format: Lee LM, Klein P, Velazy R. Breast atypical hyperplasia and guideline compliance [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-12-13.