Citations

Abstract Introduction: Estrogen receptor beta (ERβ), which is highly expressed in benign breast epithelium, is postulated to function as a tumor suppressor of breast cancer. Atypias of the breast increase the lifetime risk of breast cancer four-fold. However, little is known about ERβ expression in association with atypias or whether ERβ plays a role in mitigating breast cancer risk in high-risk individuals. We therefore undertook this study to examine the relationship of ERβ expression in atypias and adjacent normal lobules with the risk of subsequent breast cancer. Methods: We studied women in a well-characterized benign breast disease cohort with atypical ductal hyperplasia (ADH) or atypical lobular hyperplasia (ALH) diagnosed from 1967 to 1991. Nuclear and cytoplasmic ERβ expression was assessed via immunohistochemistry in both the atypical hyperplasia epithelium (atypia) and background normal lobules for percent (scores 0-4 for <1%, 1-25%, 26-50%, 51-75%, >75%, respectively) and intensity (scores 0-3 for negative, weak, intermediate, strong, respectively) using a highly specific ERβ monoclonal antibody (PPG5/10). For nuclear staining, an ERβ sum score (percent + intensity, range 0-7) was created and grouped as low (0-2), moderate (3-5) or high (6-7). Competing risks regression was used to assess the association of ERβ expression with future breast cancer risk while also accounting for the competing risk of death from other causes. Results: 171 women, median age 56, were studied (79 ADH and 92 ALH). Median follow-up was 15 years overall, and 36 women developed breast cancer at a median of 13 years after their atypia biopsy. ERβ expression was lower in the atypia versus normal lobules whether evaluated by nuclear percent stained, nuclear intensity or cytoplasmic intensity (all p < 0.001). For nuclear staining specifically, ERβ expression in the atypia was low in 44 (26%), moderate in 117 (68%) and high in only 10 (6%) based on the sum score. In contrast, ERβ was higher in the normal lobules with a majority showing high expression (n = 96, 56%), moderate expression in 74 (43%) and low expression in only 1 (0.6%). Lower ERβ nuclear expression in the atypia was associated with increased breast cancer risk, whether evaluated by percent staining, intensity or sum score; the same was true for ERβ nuclear expression in the background normal lobules. Low ERβ expression in the atypia (sum score 0-2) was associated with a 2-fold increased risk of subsequent breast cancer compared to atypia with moderate-high expression (sum score 3-7), HR 2.0, 95% CI: 1.02-3.8, p = 0.04. Lower ERβ expression in the normal lobules was also associated with an increased risk of future breast cancer: HR = 2.5 (95% CI: 1.3-5.1, p = 0.009) for low-moderate versus high expression. Conclusions: Increased ERβ expression in normal and atypical lobules was associated with a significantly decreased risk of breast cancer in our high-risk patient cohort. These data suggest that in women with atypical hyperplasia, ERβ expression is protective against the future development of breast cancer. ERβ may serve as a useful biomarker to further stratify breast cancer risk in women with benign breast disease. Citation Format: Tina J. Hieken, Jodi M. Carter, John R. Hawse, IV, Tanya L. Hoskin, Marlene Frost, Lynn C. Hartmann, Derek C. Radisky, Daniel W. Visscher, Vernon S. Pankratz, Amy C. Degnim. ERβ expression and breast cancer risk prediction for women with atypias. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr A03.

Abstract Estrogen receptor (ER) β is highly expressed in normal breast epithelium and a putative tumor suppressor. Atypical hyperplasia substantially increases breast cancer risk, but identification of biomarkers to further improve risk stratification is needed. We evaluated ERβ expression in breast tissues from women with atypical hyperplasia and association with subsequent breast cancer risk. ERβ expression was examined by immunohistochemistry in a well-characterized 171-women cohort with atypical hyperplasia diagnosed 1967–1991. Nuclear ERβ percent and intensity was scored in the atypia and adjacent normal lobules. An ERβ sum score (percent + intensity) was calculated and grouped as low, moderate, or high. Competing risks regression was used to assess associations of ERβ expression with breast cancer risk. After 15-year median follow-up, 36 women developed breast cancer. ERβ expression was lower in atypia lobules in than normal lobules, by percent staining and intensity (both P < 0.001). Higher ERβ expression in the atypia or normal lobules, evaluated by percent staining, intensity or sum score, decreased the risk of subsequent breast cancer by 2-fold (P = 0.04) and 2.5-fold (P = 0.006). High normal lobule ERβ expression conferred the strongest protective effect in premenopausal women: the 20-year cumulative incidence of breast cancer was 0% for women younger than 45 years with high versus 31% for low–moderate ERβ expression (P = 0.0008). High ERβ expression was associated with a significantly decreased risk of breast cancer in women with atypical hyperplasia. These data suggest that ERβ may be a useful biomarker for risk stratification and a novel therapeutic target for breast cancer risk reduction. Cancer Prev Res; 8(11); 1084–92. ©2015 AACR.

Abstract Purpose: Breast biopsies with benign findings (benign breast disease [BBD]) outnumber biopsies revealing in-situ or invasive cancer 4:1, providing an opportunity to identify histopathological features that predict breast cancer risk. Greater degrees of involution of terminal duct lobular units (TDLUs), the structures within the breast that produce milk and the primary source of breast cancer precursors, have been inversely associated with breast cancer risk among women with BBD. We recently developed measures to quantitate levels of TDLU involution, which demonstrate high inter/intra pathologist reproducibility. Here we assessed whether TDLU counts/100mm2 and median TDLU span (microns), two measures inversely related to degree of TDLU involution, are associated with subsequent breast cancer risk among women with BBD. Methods: From the Mayo BBD cohort (n = 9,376), we evaluated benign biopsies from 99 women who later developed breast cancer (cases) and 145 age-matched controls who did not develop breast cancer. Digitized images of biopsy sections were reviewed to enumerate TDLUs/mm2 and measure median TDLU span (microns) for up to ten normal TDLUs. Breast cancer risk factors were available from questionnaires or medical records. To assess associations with breast cancer risk, subjects were categorized into quartile levels of TDLU counts and median TDLU spans, based on data from controls. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using multivariable conditional logistic regression models, adjusted for histologic type of BBD, family history of breast cancer and menopausal hormone use. Results: Compared to controls, women who developed breast cancer had higher median number of TDLU counts/100mm2 (28 vs 20, p = 0.03) and larger TDLU spans (300 vs 267 microns, p = 0.14). In multivariable models higher TDLU counts (quartile4 vs. quartile1, OR = 2.44, 95%CI = 0.96-6.19, ptrend = 0.02) and larger TDLU span measures (quartile4 vs. quartile1, OR = 2.83, 95%CI = 1.13-7.06, ptrend = 0.03) were associated with subsequent diagnosis of breast cancer. Combinatorial metrics of TDLU counts with median TDLU span measures identified women at higher risk; specifically, women above the median for both TDLU span and TDLU counts had an OR = 3.75 (95%CI = 1.40-10.00, ptrend = 0.008), compared with women below the median for TDLU span and TDLU counts. Conclusion: These data show that lack of TDLU involution, as measured by increased persistence of TDLU counts, larger median TDLU spans and cross-classification using these measures was associated with increased breast cancer risk among women with BBD, extending prior work in this cohort based on other TDLU involution metrics. Future studies to identify determinants of TDLU involution, its association with breast cancer risk and its potential as an intermediate endpoint in prevention studies warrant consideration. Citation Format: Jonine D. Figueroa, Ruth Pfeiffer, Maya Palakal, Amy C. Degnim, Derek Radisky, Lynn C. Hartmann, Marlene Frost, Melody L. Stallings Mann, Louise A. Brinton, Daphne Papathomas, Daniel Visscher, Mark E. Sherman. Standardized measures of lobular involution and subsequent breast cancer risk among women with benign breast disease. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4682. doi:10.1158/1538-7445.AM2015-4682

Abstract Although the association between benign breast disease (BBD) and risk of subsequent breast cancer is well-established, no previous studies have compared characteristics of breast cancers in women with a history of BBD to characteristics of cancers in the general population. In this study, we compared the characteristics of 109 breast cancers that developed in a population of African-American women with a history of benign breast disease (BBD population) to 10,601 breast cancers that developed in a general population of African-American women whose cancers were recorded by the Metropolitan Detroit Cancer Surveillance System (MDCSS population). The populations were compared on demographic characteristics such as age, marital status, and previous cancers, as well as clinical characteristics such as tumor hormone receptor status, grade, stage, behavior, size, and treatment. Overall and breast cancer-specific survival were also compared between populations. Women in the BBD population developed lower grade, earlier stage cancers that were more likely to be hormone receptor-positive and less likely to exhibit invasive behavior. Women in the BBD population were also significantly less likely to die from breast cancer after ten years of follow-up. These results suggest that although women with a history of BBD are at greater breast cancer risk, their breast cancers may be more likely to be detected early, leading to better breast cancer-specific survival. Citation Format: Susanna D. Mitro, Rouba Ali-Fehmi, Sudeshna Bandyopadhyay, Baraa Alosh, Bassam Albashiti, Quratulain Ahmed, Derek C. Radisky, Marlene H. Frost, Amy C. Degnim, Julie J. Ruterbusch, Michele L. Cote. Clinical characteristics of breast cancers in African American women with benign breast disease: A comparison to the Surveillance, Epidemiology and End Results Program. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr B39. doi:10.1158/1538-7755.DISP13-B39

Abstract Introduction: Histologic characteristics of nonmalignant breast tissues (epithelial proliferation and involution) are associated with future breast cancer (BC) risk. We evaluated immune infiltration (lobulitis) in benign breast lobules and its association with features of BC risk. Methods: We analyzed archived nonmalignant breast tissue samples from 81 women in age-matched groups of varying cancer risk: 27 with benign breast disease (BBD) who later developed BC (cases), 27 with BBD without subsequent BC (controls), and 27 normal women without clinical breast disease from the Komen Tissue Bank at Indiana University (KTB). Up to 10 lobules in each sample were characterized by H&E for lobulitis, involution (none, partial, complete), and fibrocystic (FC) status (normal, nonproliferative, proliferative). Lobulitis was defined by H&E staining as lymphocyte nuclei in the intralobular stroma at low magnification and between adjacent acini at high magnification. Data was analyzed by mixed effects logistic regression. Results: Median age was 57 years (range 37-70). Among 81 breast tissue samples, 750 lobules were evaluated: 249 in BBD Cases, 265 in BBD Controls, and 236 in KTB donors. 56% of lobules were normal and 44% were FC, with 87% of FC lobules occurring in BBD samples. Lobulitis was present in 44% of lobules and varied according to subject age and individual lobule features. Younger women were more likely to have lobulitis (p=0.002); among women <50 the median proportion of lobules with lobulitis was 50%, versus 30% among women 50+. Lobulitis was less frequent in lobules with complete involution (37%) compared to partial (74%) or no involution (84%), p<0.0001. Lobulitis was common in normal lobules (52%) and decreased with increasing epithelial abnormality-39% of nonproliferative lobules and 27% of proliferative lobules (p<0.0001). In multivariate analysis including all 3 variables, all 3 remained significantly associated with lobulitis: age (p=0.03), proliferation (p<0.0001), and involution (p=0.0001). Lobules with lobulitis were less frequent in groups of women with increased breast cancer risk-55% of lobules in normal KTB samples, 43% in BBD controls, and 35% in BBD cases (p = 0.02). Conclusion: Lobulitis is common in normal and benign breast tissue lobules but varies with age, involution status, and epithelial abnormality. Further work is needed to understand the role of immune infiltrates in breast cancer risk. Citation Format: Rushin D. Brahmbhatt, Daniel W. Visscher, Tanya L. Hoskin, Derek C. Radisky, Linda M. Murphy, Melody L. Stallings Mann, Erin Miller, Vernon S. Pankratz, Lynn C. Hartmann, Marlene H. Frost, Amy C. Degnim. Immune infiltration of normal and benign breast lobules varies in breast tissues based on cancer risk. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1652. doi:10.1158/1538-7445.AM2014-1652

Abstract Background: Mammographic breast density (MBD) reflects the proportion of fibroglandular tissue in the breast, and is an established risk factor for breast cancer. Benign breast disease (BBD) is also a known risk factor for breast cancer. We previously showed an association between lobular involution (physiologic atrophy) and MBD in a large cohort study of women with BBD. We performed a comprehensive evaluation of the association of histologic features of BBD with MBD. Methods: The Mayo BBD cohort includes women, 18 to 85 years, who were diagnosed with BBD at Mayo Clinic in Rochester, MN between 01/01/1967 and 12/31/1991. For this study, we included women who had a mammogram within 6 months of BBD diagnosis, and diagnosed with BBD between 1985 and 1991 when parenchymal pattern of breast density was clinically recorded. Risk factor information such as age, and body mass index (BMI) was collected from medical records. Parenchymal pattern, assessed clinically and previously used in multiple studies of MBD and risk, classified breast density based on extent and type of density, into four categories: N1 (non-dense, no ducts visible); P1 (ductal prominence occupying <25% breast); P2 (prominent ductal pattern occupying >25% of the breast; DY (homogenous plaque-like areas of density). All assessments of benign breast tissue were performed by expert breast pathologists blinded to both MBD and BBD reports. Histologic characteristics included overall impression (non-proliferative disease (NPD), proliferative disease without atypia (PDWA), and atypical hyperplasia (AH)), proportion of normal lobules that were involuted (no (0%), partial (1 to 74%), or complete (≥75%)), type of AH (ADH or ALH), ductal and lobular hyperplasia, calcifications, sclerosing adenosis, columnar alteration, cyst, fibroadenoma, marked fibrosis, intra-ductal papilloma, radial scar (number and size), duct ectasia, and mucocele like tumors. Associations of parenchymal pattern with BBD characteristics were examined using multicategorical nominal logistic regression models. We first examined associations after adjustment for age and BMI. All variables statistically significant (p<0.05) in these models were then simultaneously included in a fully-adjusted model. Results: Of 2,257 women in the study, 14% were <40 years old, 52.7% between 40- 59 years, and 32.9% were ≥60 years. In this sample, 55.2% of women had NPD, 36% had PDWA, and AH in 8.8%. MBD was classified as N1 in 21.8%, P1 in 12.6%, P2 in 23.7% and DY in 41.9%. Age- and BMI-adjusted analyses showed that there was an association of parenchymal pattern with overall impression, lobular involution, ductal hyperplasia, sclerosing adenosis, columnar alteration, cyst, duct ectasia and fibrosis. Multivariate analyses found that women of younger age (p<0.001) and with lower BMI (p<0.001), presence of fibrosis (p<0.001) and no involution (p=0.016) were more likely to have P2 or DY parenchymal pattern than women without those characteristics. Conclusion: Among women with benign breast disease, higher MBD is associated with younger age, lower BMI, fibrosis, and lack of lobular involution. These findings, concordant with other studies of MBD, provide insight into underlying mechanisms by which MBD and BBD contribute to breast cancer risk. Citation Format: Karthik Ghosh, Robert A Vierkant, Ryan D Frank, Daniel W Visscher, Vernon S Pankratz, Christopher G Scott, Derek C Radisky, Marlene H Frost, Lynn C Hartmann, Amy C Degnim, Celine M Vachon. Association between mammographic breast density and histologic features of benign breast disease [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-10-14.

Abstract Introduction: Current models to predict breast cancer risk do not differentiate risk for estrogen receptor (ER) positive and negative breast cancer (BC), despite growing evidence that these tumors are biologically very different. We hypothesized that women with ER+ BC cancers have different clinical risk factors and histologic findings on prior benign breast biopsies than those with ER- BC. Methods: After IRB approval, we examined associations of age at benign biopsy and histologic features of the benign biopsy with ER status of incident BCs within the Mayo Benign Breast Disease Cohort. Benign biopsy slides were reviewed for extent of lobular involution and degree of epithelial proliferation by a single breast pathologist blinded to BC events. Invasive BCs occurring within 15 years after benign biopsy were classified as ER+ if ER staining was >1%. BC case-only associations with ER status were evaluated using multivariate logistic regression. Full-cohort hazard ratios (HR) and 95% confidence intervals (CI) for risk of ER-specific subtypes were estimated using Cox proportion hazards regression. Results: Among 13,410 women undergoing a benign breast biopsy from 1967-2001, 656 invasive BCs (459 ER+, 106 ER, 106 unknown) occurred within 15 years. Women who developed ER+ and ER- BCs were similar in age at the time of their prior benign breast biopsy (p=0.34). Although benign biopsies in women who later developed ER+ BC were more likely to show complete involution (23% vs 15% for ER- BC), this was not statistically significant (p=0.06). However, the degree of epithelial proliferation was significantly associated with ER status of later BCs (p=0.001), with ER+ BCs more likely than ER- BCs to have had a prior biopsy with atypical hyperplasia (16% vs 8%), and ER+ BCs less likely than ER- BCs to have had a prior biopsy with proliferative disease without atypia (33% vs 52%); this association remained after multivariate adjustment (p=0.003). We further pursued the association of epithelial proliferation with differential risk of ER+ and ER- BC in our overall cohort of 13,410 women (Table 1). Compared to women with non-proliferative disease, women with proliferative disease +/- atypia had ∼2-fold hazard ratios for ER- BC, whereas hazard ratios for ER+ BC were higher in women with atypical hyperplasia (∼4-fold) compared to proliferative disease. Hazard Ratio of ER+ and ER- BC within 15 years of BBD based upon degree of epithelial proliferation at benign biopsyCancer TypeGroupNN EventsHazard Ratio (95% CI)p-valueInvasive ER- ≤15 yearsNP8478421.00 (ref)<0.0001 PD4229542.63 (1.76, 3.93) AH70382.60 (1.22, 5.54) Invasive ER+ ≤15 yearsNP84782321.00 (ref)<0.0001 PD42291511.33 (1.09, 1.64) AH703744.41 (3.39, 5.73) NP=nonproliferative disease, PD=proliferative disease without atypia; AH=atypical hyperplasia Conclusion: ER+ and ER- breast cancers appear to have different features on prior benign breast biopsy, with atypical hyperplasia showing increased risk for both types of breast cancer, but a greater risk for ER+ tumors. Citation Format: Amy C Degnim, Derek C Radisky, Robert A Vierkant, Ryan D Frank, Marlene H Frost, Vernon S Pankratz, Celine M Vachon, Tanya L Hoskin, Julie M Cunningham, Chen Wang, Jean-Pierre Kocher, Teresa M Allers, Joanne L Johnson, Tina J Hieken, Karthik Ghosh, Lynn C Hartmann, Daniel W Visscher. Histologic features of benign breast biopsy tissue and association with ER positive and ER negative breast cancer in the Mayo BBD cohort study [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-10-06.

Abstract Objective: Contralateral PM (CPM) and Bilateral PM (BPM) markedly decrease, but do not completely eliminate the possibility of development of a new BC on the side of the PM. Given the relative infrequency of its occurrence, little is known about the clinical characteristics, presentation, and management of patients who develop BC after PM. Our aim was to review our institutional experience of BC occurring after PM. Methods: Between 1960 and 1993, 1,065 women underwent BPM and 1,643 women with unilateral BC treated with therapeutic mastectomy underwent a CPM. Medical records were reviewed and study-specific questionnaires were sent to all women at 10 years and 20 years after PM. BC after PM included locoregional invasive BC or DCIS on the side of the PM. Results: Thirteen patients who underwent BPM developed BC after PM. Twelve patients who underwent CPM developed a subsequent BC on the side of the CPM. The median follow-up time from PM was 22 years (range 3-34). Detailed clinical characteristics of BC after PM are shown in Table 1. Presentations included: disease limited to the axilla without evidence of a local primary 4 (16%); synchronous local and axillary disease 1 (4%); synchronous local disease and distant metastases 4 (16%); clinically isolated local disease 17 (68%). Characteristics of BC Following PM All Patients (n=25)BPM Cohort (n=13)CPM Cohort (n=12)Median age at diagnosis of BC after PM56 (range 38-81)58 (range 38-71)54 (range 39-81)Median time to development of BC after PM (years)7 (range 1-25)6 (range 2-25)8 (range 1-21)Presentation Self-detected abnormality23 (92%)12 (92%)11 (92%)Screening mammogram1 (4%)02 (16%)Not known1 (4%)1 (8%)0Local disease only17 (68%)10 (77%)7 (58%)-Sub-areolar7 (41%)6 (40%)1 (8%)-UOQ/axillary tail2 (12%)02 (16%)-Lower/inframmamary crease2 (12%)1 (10%)1(8%)Chest wall or unspecified6 (35%)3 (30%)3 (25%)Local & regional (axillary) disease1 (4%01 (8%)Axillary BC without evidence of local primary4 (16%)1 (8%)3 (25%)Synchronous local and distant disease3 (12%)2 (15%)1 (8%) Of the 17 patients with isolated local disease, 11 (65%) underwent a completion/redo mastectomy, local excision of the tumor was performed in 5 (29%), and surgical management was unknown in 1 (6%). Ten of 17 (59%) underwent axillary lymph node dissection, 1 (6%) underwent sentinel lymph node biopsy, 1 did not undergo axillary staging, and axillary management was unknown in 5 (29%). Median tumor size was 0.9 cm (range 0.3-3.5) and only 1 of 17 (6%) patients was confirmed to have pathologic nodal involvement. Twelve of 17 (71%) received some type of adjuvant therapy: chemotherapy and/or endocrine therapy 3 (18%); radiotherapy 2 (12%); both 5 (29%); none 5 (29%). With a median follow-up of 7 years since diagnosis of local BC after PM, there has been one isolated local recurrence and 2 distant recurrences as first event. Conclusion: BC can occur after PM. With rising rates of PM, understanding management of BC after PM is important. Most common presentation is local disease and can be managed with resection with consideration of adjuvant therapy. Multidisciplinary management of these cases is needed. Citation Format: Robert W Mutter, Tanya L Hoskin, Marlene H Frost, Joanne L Johnson, Lynn C Hartmann, Judy C Boughey. Breast cancer (BC) following prophylactic mastectomy (PM), a clinical entity: Presentation, management, and outcomes [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-12-05.