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Ghosh, Karthik

Mayo Clinic

Mayo Clinic

Citations 56

Evaluation of 2 breast cancer risk models in a benign breast disease cohort
Frank, Ryan D. , Vierkant, Robert A. , Frost, Marlene H., Ghosh, Karthik, Brandt, Kathleen R. , Visscher, Daniel W., Hartmann, Lynn C. , Vachon, Celine M. , Radisky, Derek C. , Degnim, Amy C , Vachon, Celine M. , Vierkant, Robert A , Winham, Stacey J. , Sherman, Mark E. , Degnim, Amy C.

Cancer | June 22, 2018 | Volume: 124 | Issue: 16 | Pages: 3319-3328

10.1002/cncr.31528 Get It

Background More than 1.5 million women per year have a benign breast biopsy resulting in concern about their future breast cancer (BC) risk. This study examined the performance of 2 BC risk models that integrate clinical and histologic findings in this population. Methods The BC risk at 5 and 10 years was estimated with the Breast Cancer Surveillance Consortium (BCSC) and Benign Breast Disease to Breast Cancer (BBD‐BC) models for women diagnosed with benign breast disease (BBD) at the Mayo Clinic from 1997 to 2001. Women with BBD were eligible for the BBD‐BC model, but the BCSC model also required a screening mammogram. Calibration and discrimination were assessed. Results Fifty‐six cases of BC were diagnosed among the 2142 women with BBD (median age, 50 years) within 5 years (118 were diagnosed within 10 years). The BBD‐BC model had slightly better calibration at 5 years (0.89; 95% confidence interval [CI], 0.71‐1.21) versus 10 years (0.81; 95% CI, 0.70‐1.00) but similar discrimination in the 2 time periods: 0.68 (95% CI, 0.60‐0.75) and 0.66 (95% CI, 0.60‐0.71), respectively. In contrast, among the 1089 women with screening mammograms (98 cases of BC within 10 years), the BCSC model had better calibration (0.94; 95% CI, 0.85‐1.43) and discrimination (0.63; 95% CI, 0.56‐0.71) at 10 years versus 5 years (calibration, 1.31; 95% CI, 0.94‐2.25; discrimination, 0.59; 95% CI, 0.46‐0.71) where discrimination was not different from chance. Conclusions The BCSC and BBD‐BC models were validated in the Mayo BBD cohort, although their performance differed by 5‐year risk versus 10‐year risk. Further enhancement of these models is needed to provide accurate BC risk estimates for women with BBD.
Model for Predicting Breast Cancer Risk in Women With Atypical Hyperplasia
Frank, Ryan D. , Dupont, William D. , Vierkant, Robert A. , Frost, Marlene H., Vachon, Celine M. , Ghosh, Karthik, Carter, Jodi M. , Denison, Lori A., Broderick, Brendan T., Hartmann, Lynn C. , Visscher, Daniel W., Hoskin, Tanya L. , Broderick, Brendan, Radisky, Derek C. , Vierkant, Robert A , Degnim, Amy C. , Winham, Stacey J. , Pankratz, V. Shane , Vachon, Celine M. , Hieken, Tina J. , Carter, Jodi

Journal of Clinical Oncology | April 20, 2018 | Volume: 36 | Issue: 18 | Pages: 1840-1846

10.1200/jco.2017.75.9480 Get It

Purpose Women with atypical hyperplasia (AH) on breast biopsy have an aggregate increased risk of breast cancer (BC), but existing risk prediction models do not provide accurate individualized estimates of risk in this subset of high-risk women. Here, we used the Mayo benign breast disease cohort to develop and validate a model of BC risk prediction that is specifically for women with AH, which we have designated as AH-BC. Patients and Methods Retrospective cohorts of women age 18 to 85 years with pathologically confirmed benign AH from Rochester, MN, and Nashville, TN, were used for model development and external validation, respectively. Clinical risk factors and histologic features of the tissue biopsy were selected using L1-penalized Cox proportional hazards regression. Identified features were included in a Fine and Gray regression model to estimate BC risk, with death as a competing risk. Model discrimination and calibration were assessed in the model-building set and an external validation set. Results The model-building set consisted of 699 women with AH, 142 of whom developed BC (median follow-up, 8.1 years), and the external validation set consisted of 461 women with 114 later BC events (median follow-up, 11.4 years). The final AH-BC model included three covariates: age at biopsy, age at biopsy squared, and number of foci of AH. At 10 years, the AH-BC model demonstrated good discrimination (0.63 [95% CI, 0.57 to 0.70]) and calibration (0.87 [95% CI, 0.66 to 1.24]). In the external validation set, the model showed acceptable discrimination (0.59 [95% CI, 0.51 to 0.67]) and calibration (0.91 [95% CI, 0.65 to 1.42]). Conclusion We have created a new model with which to refine BC risk prediction for women with AH. The AH-BC model demonstrates good discrimination and calibration, and it validates in an external data set.
Screening mammography rates in women with diabetes.
Tran, Christine , Wang, Amy T. , Johnson, Ryan, Ghosh, Karthik, Shah, Nilay D.

Journal of Clinical Oncology | February 24, 2017 | Volume: 32 | Issue: 26_suppl | Pages: 25-25

10.1200/jco.2014.32.26_suppl.25 Get It

25 Background: Women with diabetes are at an increased risk of developing breast cancer, present with later stage disease, and experience higher breast cancer-specific mortality compared to nondiabetic women. Thus, it is imperative that diabetic women undergo routine screening mammography. Previous studies have shown conflicting results with smaller studies showing lower screening mammography rates among diabetics while a study using national self-report data showed that diabetic women were equally likely to be screened compared to nondiabetic women. Given the conflicting data and limitations of previous studies, we aimed to study receipt of mammography in diabetic women using a nationally representative administrative claims database. Methods: This was a retrospective study using a nationally representative administrative claims database from January 1, 2010, through December 31, 2012. We compared rates of receipt of mammography within a 2-year time frame in diabetic and nondiabetic women ages 40 to 64. We used Healthcare Effectiveness Data and Information Set (HEDIS) logic to define women with diabetes. We used CPT and ICD-9 codes to identify mammogram services received. We calculated odds ratios with 95% confidence intervals to compare mammogram rates among diabetics compared to nondiabetics. Results: 1,723,674 nondiabetic women and 133,973 diabetic women were identified. Among women ages 40 to 49, diabetic women had significantly decreased mammography rates compared to nondiabetic women (OR 0.84; 95% CI 0.83, 0.85). Rates were also lower in diabetic women ages 50 to 64 (OR 0.88; 95% CI 0.88, 0.91). Despite lower mammography rates among diabetics, diabetic women had 1.78 times more visits than nondiabetic women. Conclusions: Women with diabetes are less likely to undergo routine screening mammography than women without diabetes, despite having more encounters with health care providers. This study serves as a reminder to provide timely preventive health services to all patients regardless of medical comorbidities.
Extent of atypical hyperplasia stratifies breast cancer risk in 2 independent cohorts of women
Dupont, William D. , Vierkant, Robert A. , Frank, Ryan D. , Frost, Marlene H., Winham, Stacey J. , Smith, Jeffrey R. , Page, David L., Vachon, Celine M. , Ghosh, Karthik, Denison, Lori A., Carter, Jodi M. , Hartmann, Lynn C. , Visscher, Daniel W., Radisky, Derek C. , Hoskin, Tanya L. , Degnim, Amy C. , Sanders, Melinda E. , Vachon, Celine M. , Hieken, Tina J. , Winham, Stacey J , Vierkant, Robert A , Carter, Jodi

Cancer | June 29, 2016 | Volume: 122 | Issue: 19 | Pages: 2971-2978

10.1002/cncr.30153 Get It

BACKGROUNDWomen with atypical hyperplasia (AH) on breast biopsy have a substantially increased risk of breast cancer (BC). Here the BC risk for the extent and subtype of AH is reported for 2 separate cohorts.METHODSAll samples containing AH were included from 2 cohorts of women with benign breast disease (Mayo Clinic and Nashville). Histology review quantified the number of foci of atypical ductal hyperplasia (ADH) and atypical lobular hyperplasia (ALH). The BC risk was stratified for the number of AH foci within AH subtypes.RESULTSThe study included 708 Mayo AH subjects and 466 Nashville AH subjects. In the Mayo cohort, an increasing number of foci of AH was associated with a significant increase in the risk of BC both for ADH (relative risks of 2.61, 5.21, and 6.36 for 1, 2, and ≥3 foci, respectively; P for linear trend = .006) and for ALH (relative risks of 2.56, 3.50, and 6.79 for 1, 2, and ≥3 foci, respectively; P for linear trend = .001). In the Nashville cohort, the relative risks of BC for ADH were 2.70, 5.17, and 15.06 for 1, 2, and ≥3 foci, respectively (P for linear trend < .001); for ALH, the relative risks also increased but not significantly (2.61, 3.48, and 4.02, respectively; P = .148). When the Mayo and Nashville samples were combined, the risk increased significantly for 1, 2, and ≥3 foci: the relative risks were 2.65, 5.19, and 8.94, respectively, for ADH (P < .001) and 2.58, 3.49, and 4.97, respectively, for ALH (P = .001).CONCLUSIONSIn 2 independent cohort studies of benign breast disease, the extent of atypia stratified the long‐term BC risk for ADH and ALH. Cancer 2016;122:2971‐2978. © 2016 American Cancer Society.
Low-Grade Malignant Proliferating Tricholemmal Tumor Associated With Occult Ductal Carcinoma In Situ of the Breast
Lopez, Jonathan J., Chen, Beiyun, Ghosh, Karthik, Peters, Margot S.

The American Journal of Dermatopathology | May 25, 2016 | Volume: 38 | Issue: 10 | Pages: e144-e146

10.1097/dad.0000000000000582 Get It

Abstract: Malignant proliferating tricholemmal tumor (MPTT) is a rare adnexal neoplasm most commonly located on the scalp. We a 62-year-old woman who presented to her local physician with a palpable but not visible nodule of the left breast, initially diagnosed as squamous cell carcinoma. Histopathological evaluation of the reexcision specimen incidentally revealed ductal carcinoma in situ. On referral to our institution, the skin biopsy specimen was reviewed and interpreted as a low-grade MPTT. This patient and 2 previously reported cases of MPTT involving breast skin highlight presentation of a rare tumor at an unusual site and the potential for misdiagnosis as squamous cell carcinoma. Reexcision provided the unexpected benefit for our patient of early diagnosis of ductal carcinoma in situ not revealed by imaging.
Clinicopathologic features of breast cancers that develop in women with previous benign breast disease
Visscher, Daniel W., Frost, Marlene H., Hartmann, Lynn C. , Frank, Ryan D. , Vierkant, Robert A. , McCullough, Ann E. , Winham, Stacey J. , Vachon, Celine M. , Ghosh, Karthik, Brandt, Kathleen R. , Farrell, Ann , Tarabishy, Yaman, Haddad, Tufia C. , Kraft, Ruth, Farrell, Ann M, Kraft, Ruth A, Radisky, Derek C. , Vachon, Celine M. , Hieken, Tina J. , Degnim, Amy C. , Winham, Stacey J , Vierkant, Robert A

Cancer | October 29, 2015 | Volume: 122 | Issue: 3 | Pages: 378-385

10.1002/cncr.29766 Get It

BACKGROUNDWomen with benign breast disease (BBD) have an increased risk of developing breast cancer (BC). Nearly 30% of all BCs develop in women with prior BBD. Information regarding features of the expected number of BCs after BBD would enhance individualized surveillance and prevention strategies for these women. In the current study, the authors sought to characterize BCs developing in a large cohort of women with BBD.METHODSThe current study cohort included 13,485 women who underwent breast biopsy for mammographic or palpable concerns between 1967 and 2001. Biopsy slides were reviewed and classified as nonproliferative disease, proliferative disease without atypia, or atypical hyperplasia. BCs were identified by follow‐up questionnaires, medical records, and Tumor Registry data. BC tissues were obtained and reviewed.RESULTSWith median follow‐up of 15.8 years, 1273 women developed BC. The majority of BCs were invasive (81%), of which 61% were ductal, 13% were mixed ductal/lobular, and 14% were lobular. Approximately two‐thirds of the BC cases were intermediate or high grade, and 29% were lymph node positive. Cancer characteristics were similar across the 3 histologic categories of BBD, with a similar frequency of ductal carcinoma in situ, invasive disease, tumor size, time to invasive BC, histologic type of BC, lymph node positivity, and human epidermal growth factor receptor 2 positivity. Women with atypical hyperplasia were found to have a higher frequency of estrogen receptor‐positive BC (91%) compared with women with proliferative disease without atypia (80%) or nonproliferative disease (85%) (P = .02).CONCLUSIONSA substantial percentage of all BCs develop in women with prior BBD. The majority of BCs after BBD are invasive tumors of ductal type, with a substantial number demonstrating lymph node positivity. Of all the BCs in the current study, 84% were estrogen receptor positive. Prevention therapy should be strongly encouraged in higher‐risk women with BBD. Cancer 2016;122:378–385. © 2015 American Cancer Society.
Abstract P6-10-14: Association between mammographic breast density and histologic features of benign breast disease
Ghosh, Karthik, Frank, Ryan D. , Visscher, Daniel W., Frost, Marlene H., Hartmann, Lynn C. , Vachon, Celine M. , Vierkant, Robert A. , Pankratz, V. Shane , Scott, Christopher G. , Radisky, Derek C. , Degnim, Amy C. , Vachon, Celine M.

Cancer Research | May 4, 2015 | Volume: 75 | Issue: 9_Supplement | Pages: P6-10-14-P6-10-14

10.1158/1538-7445.sabcs14-p6-10-14 Get It

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 &lt;25% breast); P2 (prominent ductal pattern occupying &gt;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&lt;0.05) in these models were then simultaneously included in a fully-adjusted model. Results: Of 2,257 women in the study, 14% were &lt;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&lt;0.001) and with lower BMI (p&lt;0.001), presence of fibrosis (p&lt;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 P6-10-06: Histologic features of benign breast biopsy tissue and association with ER positive and ER negative breast cancer in the Mayo BBD cohort study
Frank, Ryan D. , Frost, Marlene H., Vachon, Celine M. , Cunningham, Julie M. , Kocher, Jean‐Pierre , Allers, Teresa M., Johnson, Joanne L., Ghosh, Karthik, Hartmann, Lynn C. , Visscher, Daniel W., Degnim, Amy C. , Radisky, Derek C. , Vierkant, Robert A. , Pankratz, V. Shane , Vachon, Celine M. , Hoskin, Tanya L. , Wang, Chen , Hieken, Tina J.

Cancer Research | May 4, 2015 | Volume: 75 | Issue: 9_Supplement | Pages: P6-10-06-P6-10-06

10.1158/1538-7445.sabcs14-p6-10-06 Get It

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 &gt;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)&lt;0.0001 PD4229542.63 (1.76, 3.93) AH70382.60 (1.22, 5.54) Invasive ER+ ≤15 yearsNP84782321.00 (ref)&lt;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.
Model for Individualized Prediction of Breast Cancer Risk After a Benign Breast Biopsy
Frank, Ryan D. , Frost, Marlene H., Visscher, Daniel W., Vierkant, Robert A. , Ghosh, Karthik, Tarabishy, Yaman, Vachon, Celine M. , Hartmann, Lynn C. , Radisky, Derek C. , Pankratz, V. Shane , Degnim, Amy C. , Hieken, Tina J. , Vachon, Celine M. , Vierkant, Robert A

Journal of Clinical Oncology | January 26, 2015 | Volume: 33 | Issue: 8 | Pages: 923-929

10.1200/jco.2014.55.4865 Get It

Purpose Optimal early detection and prevention for breast cancer depend on accurate identification of women at increased risk. We present a risk prediction model that incorporates histologic features of biopsy tissues from women with benign breast disease (BBD) and compare its performance to the Breast Cancer Risk Assessment Tool (BCRAT). Methods We estimated the age-specific incidence of breast cancer and death from the Mayo BBD cohort and then combined these estimates with a relative risk model derived from 377 patient cases with breast cancer and 734 matched controls sampled from the Mayo BBD cohort to develop the BBD–to–breast cancer (BBD-BC) risk assessment tool. We validated the model using an independent set of 378 patient cases with breast cancer and 728 matched controls from the Mayo BBD cohort and compared the risk predictions from our model with those from the BCRAT. Results The BBD-BC model predicts the probability of breast cancer in women with BBD using tissue-based and other risk factors. The concordance statistic from the BBD-BC model was 0.665 in the model development series and 0.629 in the validation series; these values were higher than those from the BCRAT (0.567 and 0.472, respectively). The BCRAT significantly underpredicted breast cancer risk after benign biopsy (P = .004), whereas the BBD-BC predictions were appropriately calibrated to observed cancers (P = .247). Conclusion We developed a model using both demographic and histologic features to predict breast cancer risk in women with BBD. Our model more accurately classifies a woman's breast cancer risk after a benign biopsy than the BCRAT.
Flat epithelial atypia and risk of breast cancer: A Mayo cohort study
Said, Samar M. , Visscher, Daniel W., Nassar, Aziza , Frank, Ryan D. , Vierkant, Robert A. , Frost, Marlene H., Ghosh, Karthik, Hartmann, Lynn C. , Nassar, Aziza , Radisky, Derek C. , Degnim, Amy C. , Vierkant, Robert A

Cancer | January 13, 2015 | Volume: 121 | Issue: 10 | Pages: 1548-1555

10.1002/cncr.29243 Get It

BACKGROUND Based on its cytologic features, and its co‐occurrence with atypical hyperplasia and breast cancer, flat epithelial atypia (FEA) has been proposed as a precursor lesion on the pathway to the development of breast cancer. It is often referred to as an “atypical” or high‐risk lesion. However, to the authors' knowledge, the long‐term risk of breast cancer in women with FEA is undefined. METHODS Specimens with FEA were identified among excisional breast biopsies in the Mayo Clinic Benign Breast Disease Cohort, which includes 11,591 women who had benign biopsy findings at the Mayo Clinic in Rochester, Minnesota between 1967 and 2001. Breast cancer risk among subsets of patients with FEA and nonproliferative, proliferative, and atypical hyperplasia (AH) was assessed using standardized incidence ratios (SIRs) compared with the Iowa Surveillance, Epidemiology, and End Results registry. RESULTS FEA was identified in 282 women (2.4%); 130 had associated AH (46%) and 152 (54%) were classified as having proliferative disease without atypia (PDWA). With median follow‐up of 16.8 years, the SIR for breast cancer in patients with AH plus FEA was 4.74 (95% confidence interval [95% CI], 3.17‐6.81) versus 4.23 (95% CI, 3.44‐5.13) for those with AH without FEA ( P = .59). The SIR for patients with PDWA plus FEA was 2.04 (95% CI, 1.23‐3.19) versus 1.90 (95% CI, 1.72‐2.09) for patients with PDWA without FEA ( P = .76). CONCLUSIONS FEA is an uncommon finding in women with benign breast disease. FEA does not appear to convey an independent risk of breast cancer beyond that of the associated PDWA or AH. Cancer 2015;121:1548–1555 . © 2015 American Cancer Society .