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Evaluation of Exogenous Estrogen Use in Patients with Lobular Neoplasia and Its Role in Subsequent Breast Cancer Development
Jordan Petrick
*1, Vibhusha Kolli
4, Madhuchhanda Roy
2, Mai A. Elezaby
3, Meeghan A. Lautner
1, Ashley A. Woodfin
1, Heather B. Neuman
1, Lee G. Wilke
1, Anna C. Beck
11Department of Surgery, University of Wisconsin-Madison, Madison, WI; 2Department of Pathology, University of Wisconsin-Madison, Madison, WI; 3Department of Radiology, University of Wisconsin-Madison, Madison, WI; 4University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI
Objective: Lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH), collectively referred to as lobular neoplasia (LN), are associated with an increased lifetime breast cancer risk of >20%. There is a paucity of data around the impact of hormone replacement therapy (HRT) and other exogenous hormones, including oral contraceptive pills (OCPs) on future breast cancer risk in the setting of LN. The objective of this study is to determine whether patients with history of exogenous estrogen use who develop LN are more likely to develop a future breast cancer.
Methods: Following IRB approval, a single-institution retrospective review was conducted of consecutive patients with diagnosed LCIS or ALH between 1/2009 and 12/2017 to allow for extended follow up. Patients with a prior history of breast cancer, concurrent breast cancer including if identified on excisional biopsy, known genetic mutation, or atypical ductal hyperplasia were excluded. Data were analyzed using IBM SPSS version 29.0.2.0.
Results: A total of 88 patients with LN were identified; 57 (65%) with LCIS and 31 (35%) with ALH. At time of LN diagnosis, 53 (60%) underwent surgical excision, 48 (39%) were followed in a high-risk clinic, and 13 (15%) took anti-estrogen therapy for risk reduction. 15 patients had a history of HRT use prior to LN diagnosis (17%) and 3 (3%) started HRT following LN diagnosis. An additional 10 (11%) had a history of vaginal estrogen use, 55 (63%) OCP use, and 14 (16%) other hormone-based birth control use. Median overall follow-up was 9.7 years (interquartile range [IQR] 7.2-11.4). Eleven (13%) patients developed breast cancer a median 5.4 years (IQR 2.7-6.8) after LN diagnosis. Comparing those who developed breast cancer vs. not, there was no difference in HRT use (1 [9%] vs 16 [21%], p=0.325), vaginal estrogen use (3 [27%] vs 7 [9%], p=0.110), OCP use (6 [54%] vs 49 [64%], p=0.675[ML1] ), or other hormone-based birth control (3 [27%] vs 11 [14%], p=0.402).
Conclusion: In a single-institution cohort with long-term follow up, identification and development of breast cancer in patients diagnosed with LN was not associated with use of HRT, OCPs, vaginal estrogen or other hormone-based birth control use.
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