Citations

Abstract Background: Parity reduces risk of late onset breast cancer (BC), but childbirth is associated with a transient rise in BC risk. In a prior analysis of normal breast tissues donated for research to the Komen Tissue Bank (KTB), we reported that numbers of lobules (the primary structures from which BCs arise) are increased among parous versus nulliparous women. To further define the histological features that may be related to the transient rise in post-partum BC risk, we performed an expanded histologic review of 757 breast tissues donated to the KTB by women ≤45 years of age and compared lobule number, acinar count per lobule, and abundance of immune cells, and specifically plasma cells, between nulliparous and parous women. Methods: We assessed digital scans of H&E stained tissue sections of KTB tissues for total number of lobules, and evaluated acini / lobule (ordinal categories) and lobule span (um) for ≤10 lobules per section. Masked to epidemiologic data, we subjectively assessed images including ≥5 lobules for the presence of benign breast disease (BBD), ≥3 plasma cells per section and increased immune cells in lobules. We compared parous women according to time since last birth (≤5 years or >5 years) to nulliparas (referent) using age-adjusted regression models appropriate for data type (count, continuous, ordinal, or categorical). Results: Compared to nulliparous women, parous women ≤5 years of a birth had a 1.83-fold increase in lobule counts (95% confidence interval [CI]: 1.47-2.28, P<0.001), increased plasma cells in lobules (OR=1.86; 95% CI: 1.08-3.18, P<0.025), and subjectively, increased immune cells in lobules (OR=2.46, 95% CI: 1.39-4.36, P<0.002). Comparisons of parous women ≥5 years post-partum to nulliparas revealed a 1.83-fold increase in numbers of lobules (95% CI: 1.42-2.36, P<0.001); however, lobule span in parous women was 0.89 times that of nulliparous women (95% CI: 0.80-0.99, P=0.037) and other features assessed did not show statistically significant differences. Conclusion: Histologically, normal breast tissues reveal persistently increased lobule counts and increased plasma cells and inflammation for ≤5 years post-partum compared with nulliparous women, although other lobular features decrease between ≤5 and >5 years after a birth. Future molecular studies will define how these changes in the epithelium and microenvironment during the post-partum period may inform mechanisms that mediate the transient increase in BC risk after childbirth and the reduction in BC risk that occurs later in life. Citation Format: Joshua Ogony, DereK C. Radisky, Amy C. Degnim, Marlene Frost, Tanya L. Hoskin, Michael G. Heckman, Launia J. White, Mark E. Sherman. Analysis of post-partum breast tissue to understand early onset breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4635.

Abstract Background: Biopsy diagnosis of benign breast disease (BBD) based on the most severe lesion in a sample predicts future breast cancer risk and has implications for screening and management. Lobules are the functional unit of the breast and the structures from which BBD arises. We developed and preliminarily validated an automated computational pathology algorithm to discriminate normal from BBD breast lobules as a step toward automated comprehensive characterization of benign biopsies. Methods: 152 BBD biopsies (27 training, 125 validation) from the Mayo Clinic were examined using scanned digital images of H&E stained sections. For each image, a pathologist annotated up to 10 representative lobules as normal or BBD using standard pathology criteria. A deep learning algorithm to quantify lobular features was developed using 129 lobules from 27 subjects. Nine features were identified that discriminate normal vs BBD lobules, expressing lobule size, acini size and number, acinar lumen size, proportion of lobular stroma, and capillaries. Here, we validate their performance to discriminate normal vs BBD lobules in a set of 1250 lobules from 125 subjects using area under the ROC curve (AUC) analysis. Random forest analysis was used for multivariable modeling; model performance was assessed with a tenfold cross-validation approach. Results: Median subject age was 52 years. Among the 125 validation subjects, BBD findings were nonproliferative in 39%, proliferative in 45%, and atypical hyperplasia in 16%. Sections included 552 (44%) normal lobules and 698 BBD (56%) lobules, with representation of both lobule types on each section. In univariate analyses, four individual features showed good discrimination between normal vs. BBD lobules, yielding the following AUCs: lobule size= 0.74, mean acini size= 0.75, epithelial area= 0.75, and number of acini with large lumens= 0.76. Lobule size and epithelial area were highly correlated (Spearman rank correlation r = 0.95), but both of these features showed lower correlation with mean acini size and number of acini with large lumens (each r < 0.5). With random forest modeling, number of acini with large lumens was the strongest discriminating feature, followed by mean acini size, lobule size, and epithelial area. With ten-fold cross validation of the multivariable random forest model, the overall AUC was 0.82 (95% CI: 0.79-0.85). Conclusion: Our validation showed that automated quantitative computational pathology assessment of breast lobules can discriminate normal versus BBD on a per lobule basis. This finding supports the feasibility of developing automated algorithms to classify every lesion in breast biopsies, expanding beyond visual assessment. Further studies using deep learning may reveal novel pathology features for classifying BBD biopsies with the potential to strengthen estimation of breast cancer risk. Citation Format: Amy C. Degnim, Thomas de Bel, Mark E. Sherman, Derek C. Radisky, Stacey J. Winham, Tanya L. Hoskin, Melody L. Stallings Mann, Marlene Frost, Robert A. Vierkant, Brendan T. Broderick, Ethan P. Heinzen, Rushin Brahmbhatt, Muhammad Arshad, Celine M. Vachon, Jodi M. Carter, Lori A. Denison, Daniel W. Visscher, Jeroen van der Laak. Discrimination of benign breast disease from normal lobules using an automated computational pathology algorithm [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2113.

550 Background: Ductal carcinoma in situ (DCIS) is a heterogeneous group of non-invasive cancers with varying propensity for recurrence. There are no validated markers that identify patients at risk for invasive recurrence following lumpectomy. HOXB13/IL17BR (H/I) is expressed in both DCIS and invasive cancer (Ma Cancer Cell. 2004) and associated with recurrence in stage I cancer. A 5-gene molecular grade index (MGI) distinguishes outcome in grade II disease (Ma Clin Cancer Res. 2008). We sought to determine whether H/I or MGI was associated with invasive recurrence in resected DCIS. Methods: We identified patients at Mayo Rochester who underwent lumpectomy ± radiation for DCIS between 1988 and 2001 and performed a nested case/control study. Cases were patients with ipsilateral invasive recurrence, matched to controls based on age, surgery date, length of follow-up, and adjuvant radiation. DCIS was macrodissected from paraffin sections and RNA extracted to obtain H/I and MGI RT-PCR profiles. The association of H/I and MGI with case-control status was assessed with conditional logistic regression; results reported are odds ratios (OR) with 95% confidence intervals (CI). The association of H/I and MGI as continuous variables with nuclear grade (low, intermediate, high) was estimated with Spearman's rank correlation. Results: 427 patients underwent lumpectomy for DCIS, and 33 were identified as possible cases. Histologic review excluded 8 (non-sufficient tissue or DCIS recurrence without invasion). 25 cases were matched to 48 controls (2 controls for 23 cases, 1 control for 2 cases). Both H/I (r = 0.43, p = 0.0001) and MGI (r = 0.41, p = 0.0004) were significantly correlated with nuclear grade. Positive H/I was associated with trend towards higher recurrence (OR 1.9; p = 0.22) that was most pronounced in cases/controls (15/28) treated with lumpectomy alone (OR 3.3; CI: 0.8–13.2, p = 0.09). Similarly, positive MGI was associated with a trend towards higher recurrence risk in patients treated with surgery alone (OR 2.0; CI: 0.6–6.4, p = 0.27). Conclusions: These data suggest that both HOXB13/IL17BR and MGI can identify a subset of patients with surgically resected DCIS who are at risk for invasive recurrence. Further studies in larger cohorts are needed to confirm these findings. [Table: see text]

Abstract Over one million women in the United States receive biopsy diagnoses of benign breast disease (BBD) each year, which confer a 1.5–4.0-fold increase in breast cancer risk. Studies in the general population suggest that nonsteroidal anti-inflammatory agents (NSAID) lower breast cancer risk; however, associations among women with BBD are unknown. We assessed whether NSAID use among women diagnosed with BBD is associated with lower breast cancer risk. Participants included 3,080 women (mean age = 50.3 ± 13.5 years) in the Mayo BBD surgical biopsy cohort diagnosed between January 1, 1992 and December 31, 2001 who completed breast cancer risk factor questionnaires that assessed NSAID use, and whose biopsies underwent detailed pathology review, masked to outcome. Women were followed from date of BBD biopsy to breast cancer diagnosis (main outcome) or censoring (death, prophylactic mastectomy, reduction mammoplasty, lobular carcinoma in situ or last contact). Median follow-up time was 16.4 ± 6.0 years. Incident breast cancer was diagnosed among 312 women over a median follow-up of 9.9 years. Regular non-aspirin NSAID use was associated with lower breast cancer risk [HR = 0.63; 95% confidence interval (CI) = 0.46–0.85; P = 0.002] with trends of lower risk (highest tertiles of use vs. nonuse) for greater number of years used [HR = 0.55; 95% CI = 0.31–0.97; Ptrend = 0.003), days used per month (HR = 0.51; 95% CI = 0.33–0.80; Ptrend = 0.001) and lifetime number of doses taken (HR = 0.53; 95% CI = 0.31–0.89; Ptrend = 0.003). We conclude that nonaspirin NSAID use is associated with statistically significant lower breast cancer risk after a BBD biopsy, including a dose–response effect, suggesting a potential role for NSAIDs in breast cancer prevention among patients with BBD.

Objectives Based on our previous findings that postmenopausal women with estrone (E1) and estradiol (E2) concentrations at or above 1.3 pg/ml and 0.5 pg/ml, respectively, after 6 months of adjuvant anastrozole therapy had a three-fold risk of recurrence, we aimed to identify a single-nucleotide polymorphism (SNP)-based model that would predict elevated E1 and E2 and then validate it in an independent dataset. Patients and methods The test set consisted of 322 women from the M3 study and the validation set consisted of 152 patients from MA.27. All patients were treated with adjuvant anastrozole, had on-anastrozole E1 and E2 concentrations and genome-wide genotyping. Results SNPs were identified from the M3 genome-wide association study. The best model to predict the E1-E2 phenotype with high balanced accuracy was a support vector machine model using clinical factors plus 46 SNPs. We did not have an independent cohort that is similar to the M3 study with clinical, E1-E2 phenotypes and genotype data to test our model. Hence, we chose a nested matched case-control cohort (MA.27 study) for testing. Our E1-E2 model was not validated but we found the MA.27 validation cohort was both clinically and genomically different. Conclusions We identified a SNP-based model that had excellent performance characteristics for predicting the phenotype of elevated E1 and E2 in women treated with anastrozole. This model was not validated in an independent dataset but that dataset was clinically and genomically substantially different. The model will need validation in a prospective study.

Contralateral axillary metastasis (CAM) in breast cancer is presently treated as a stage IV disease. We hypothesized that this disease pattern is a manifestation of direct aberrant lymphatic drainage and would behave more similar to advanced locoregional disease. This is a single-site, retrospective review of patients with biopsy-proven CAM from 2008–2017. Descriptive analysis was performed. Twenty-three patients met the inclusion criteria. The median disease-free interval from primary tumor treatment to diagnosis of CAM was 68 months (range, 36–155 months). This population had aggressive disease (74% local recurrences and 61% clinical evidence of cutaneous or underlying muscular invasion) and extensive locoregional therapy (70% radiated, 57% mastectomy, and 65% axillary lymph node dissection) before their presentation with CAM. Fifteen (65.2%) patients recurred after treatment of CAM; the median recurrence-free interval was 11 months (range, 5–23 months), and 12 (52.2%) patients developed distant metastases. The median distant metastasis-free survival was 14 months (range, 11–23 months), and the median overall survival was 31 months (range, 22–67.5 months). Development of CAM is associated with aggressive disease and extensive prior locoregional surgery and/or radiation. The short recurrence-free interval and high progression to additional stage IV disease suggest these patients behave similar to traditional stage IV patients with resected oligometastatic disease.

Abstract Background: High dose melphalan & autologous peripheral blood stem cell (PBSC) transplantation is increasingly utilized for primary systemic amyloidosis (AL). PBSC mobilization with filgrastim is safe in various patient & normal donor populations. While there is a case report of filgrastim-induced fatal pulmonary edema in an AL patient undergoing PBSC mobilization, we elucidate the incidence & magnitude of fluid-related complications in this patient population, describe the management & outcomes, & identify features predictive of risk. Methods: IRB approval & patient consent were obtained prior to review of medical records for all adult Mayo Clinic AL patients who underwent PBSC mobilization with filgrastim 10 mcg/kg once daily from 7/98 – 8/03. Three patient episodes were excluded: 1 refused consent & 2 had a 2nd PBSC mobilization & were included once. A fluid-related complication was defined as documented increased fluid retention (peripheral edema, pleural effusion or ascites) or use of additional therapy (diuretics, albumin or dopamine) to facilitate diuresis. Results: Sixty-three of 123 patients (51%) developed a fluid-related complication. Significant interventions were needed during mobilization & prior to PBSC transplant, including admission to ICU (n=3), hemodialysis to manage fluid status (n=3), paracentesis (n=2), & thoracentesis (n=3), including one requiring chest tube placement & pleurodesis. Patients with complications had more hospitalizations during PBSC mobilization compared to those that did not (24 vs 6; p=0.001); with 20 of 24 directly related to fluid status. While not statistically significant, the complications group was more likely to fail to collect adequate PBSC or have mobilization prematurely discontinued (6 vs 2; p=0.32). One patient in each group died suddenly during mobilization. Characteristics Predictive of Fluid-related Complications Patients with Fluid-Related Complications N (%) p-value AL Organ Involvement 1 vs 2 vs 3 23/58 (40%) 26/45 (58%) 14/20 (70%) 0.01 Kidney: yes vs no 48/85 (57%) 15/38 (40%) 0.08 Heart: yes vs no 41/61 (67%) 22/62 (35%) 0.0004 Baseline edema: yes vs no 47/77 (61%) 16/46 (35%) 0.005 Diuretic: 0 vs 1 vs >1 15/52 (29%) 37/59 (63%) 11/12 (92%) <0.0001 Albumin: ≤ 2 vs > 2 mg/dL 18/24 (75%) 45/99 (45%) 0.009 On univariate analysis patients with complications had increased septal wall thickness (median 13 vs 12 mm, p=0.05), increased total urinary protein (median 3.698 vs 2.9575 g/day, p=0.04), & lower serum albumin (median 2.8 vs 3.3 mg/dL, p=0.005). Via multivariate regression patients with albumin < 2 mg/dL had an OR=3.8 (CI 1.2 – 13.6), those with cardiac AL had an OR=5.5 (CI 2.2 – 15.4), & patients utilizing diuretics at baseline had an OR=12.1 (CI 2.8 – 61.2) for the likelihood of complications. Patients with fluid-related complications during mobilization had a lower survival rate at 100 days (78 vs 92%, p=0.003) & 1 year after PBSC transplantation (65 vs 91%, p=0.003). Conclusions: Over 50% of AL patients who undergo PBSC mobilization with filgrastim 10 mcg/kg once daily develop clinically significant fluid retention & subsequent complications. Cardiac AL, hypoalbuminemia, & diuretic use prior to filgrastim administration were more likely to develop complications. Fluid-related complications during PBSC mobilization are associated with poorer survival after transplantation for AL.

Abstract Background Prior epidemiologic studies have shown an inverse relationship of aspirin and NSAID use with breast cancer (BC) risk in the general population. Women with benign breast disease (BBD) are at an increased BC risk compared with women in the general population, and we have shown that BBD biopsies contain increased numbers of immune cells compared with normal breast tissues donated for research in the Komen Tissue Bank. We hypothesized that NSAID use among women with BBD is associated with reduced risk of BC. Methods We evaluated BC risk in relation to aspirin and NSAID use in a single institution retrospective cohort of 4,498 women who received a biopsy diagnosis of BBD between 1/1/1992 and 12/31/2001. Information on usual medication use, including average number of days used per month (0, 1-7, 8-28 and >28), was collected via questionnaires mailed after identification of participants. NSAIDs were categorized into three classes: 1) Aspirin, 2) Ibuprofen (plus other prostaglandin synthesis inhibitors), and 3) COX inhibitors. BC events were captured via medical record, questionnaires, and Tumor Registry records. Medication use was evaluated for associations with clinical and pathology features. Hazard ratios (HR) and 95% confidence intervals (CI) examining associations between medication use and BC risk were estimated using Cox regression analyses, with adjustment for age and BMI at biopsy, years between biopsy and questionnaire, and pathologic features related to BC risk (severity of BBD and degree of involution in background lobules). Tests for trend examining frequency of use were calculated from ordered values (lowest to highest) in Cox models with a one degree-of-freedom linear term. We assessed BC associations with any type of NSAID use, as well as the three subclasses. Results Information on NSAID use was available for 3,089 (69%) of the participants in the cohort; these women had a median age of 49 and did not differ in BC risk from women who did not provide data on NSAID use (p=0.46). Of the 3,089 respondents, 313 (10.1%) subsequently developed BC with median follow-up of 17 years. Age was significantly associated with use of all types of NSAIDs, with increasing use in older women. BMI at the time of biopsy, severity of BBD findings, and involution in background lobules were also associated with NSAID use; thus these factors and age were adjusted for in risk association analyses. Ever users of NSAIDs (any type) had a significantly lower risk of BC than never users (HR 0.76, CI 0.59-0.98, p=0.03), and increasing frequency of NSAID use was significantly associated with lower BC risk (HRs 0.81, 0.79, and 0.70 for regular use 1-7, 8-28, and >28 days/month), trend p=0.02. Analyses of drug classes revealed that ever use of ibuprofen (HR 0.61, CI 0.42-0.89, p=0.01) and ever use of COX inhibitors (HR 0.59, CI 0.39-0.89, p=0.01) were associated with decreased BC risk. COX inhibitors in particular showed a strong dose response effect with increasing use (HRs 0.97, 0.52, and 0.47 for regular use 1-7, 8-28, and >28 days/month), trend p<0.01. Use of aspirin was not associated with BC risk (HR 0.88, CI 0.64-1.21, p=0.44). Conclusions In this exploratory analysis, we found use of ibuprofen and other NSAIDs to be associated with decreased BC risk among women who had undergone a BBD biopsy. These findings suggest that anti-inflammatory approaches may have value in chemoprevention among women with BBD. Citation Format: Amy Degnim, Robert Vierkant, Stacey Winham, Marlene Frost, Daniel Visscher, Jodi Carter, Suneetha Kaggal, Julie Cunningham, Teresa Allers, Tanya Hoskin, Ethan Heinzen, Celine Vachon, Keith Knutson, Keith Knutson, Derek Radisky, Mark Sherman. NSAID use and breast cancer risk in a retrospective cohort of women with benign breast disease [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-08-06.

Abstract Background: Invasive lobular carcinoma (ILC) is typically strongly hormone receptor (HR) positive, with unique characteristics. It has been shown to have poor response to neoadjuvant chemotherapy (NAC) and recent studies describe the benefits of neoadjuvant endocrine therapy (NET). We sought to determine how the primary management strategy in ILC has changed over time, and the impact of ILC tumor biology on its management. Specifically, we hypothesized that use of NAC has decreased, while NET use increased. Additionally, we investigated whether NET is associated with higher rates of breast conservation surgery (BCS) than other primary management strategies. Methods: We queried the NCDB from 2010-2016 and identified all women with ILC who underwent surgical therapy. Patients with stage IV disease were excluded. First course of treatment was classified as: NAC (chemotherapy starting 31-365 days before surgery), NET (short course defined as 7-30 days before surgery; long course defined as 31-365 days before surgery), and primary surgery. Tumors were considered HR+ if they were estrogen receptor and/or progesterone receptor positive. Trends over time in first treatment strategy were compared using Cochrane-Armitage tests. The association between first treatment strategy and use of BCS was assessed using multivariable logistic regression. Results: Among 79,709 women with ILC, 94.0% were HR+/HER2-, 4.7% were HER2+, and 1.3% were triple negative. The most common primary treatment strategy was surgery (92.3%), but the percent undergoing systemic treatment before surgery increased from 7.1% in 2010 to 8.8% in 2016 (p<0.001). The use of NAC increased significantly over the study period in patients with triple negative (12.1% in 2010 to 23.7% in 2016, p=0.007) and HER2+ (12.2% in 2010 to 29.1% in 2016, p<0.001) ILC tumors. Among patients with HR+/HER2- tumors, however, the use of NAC decreased from 4.7% in 2010 to 4.2% in 2016, p=0.007, and the use of long course NET increased significantly, from 1.6% in 2010 to 2.7% in 2016, p<0.001. The use of short course NET in HR+/HER2- patients remained very low over the study period (0.4% in 2010 to 0.5% in 2016, p=0.14). Analyzing the HR+/HER2- subset, 48.4% (295/609) of patients undergoing long course NET with a cT2 tumor underwent BCS compared to 35.3% for primary surgery, 27.3% for NAC, and 24.8% for short course NET (p<0.001). Long course NET was also associated with a higher BCS rate in cT3/cT4 tumors: 22.6% BCS for long course NET, 8.3% BCS for primary surgery, 9.6% BCS for NAC, 7.8% BCS for short course NET (p<0.001). In multivariable analysis including a clinical T category by treatment interaction, long course NET was the only treatment that was associated with higher rates of BCS compared to primary surgery in cT2 (OR 1.51, 95% CI: 1.27-1.79) tumors, while both long course NET (OR 2.52, 95% CI: 1.97-3.22) and NAC (OR 1.54, 95% CI: 1.27-1.88) were associated with increased use of BCS in cT3/cT4 tumors, see Table. Conclusions: The primary management of ILC is slowly evolving over time with a decrease in primary surgery. NAC use has increased appropriately in tumor subtypes with greatest potential benefit (i.e., triple negative or HER2 positive). In HR+/HER2- disease, NAC use has decreased, however NET use has increased and in cT2+ tumors NET was associated with higher rates of BCS. Variable1Odds ratio for BCS (95% CI)p-valueAge, per 1 year increase1.04 (1.03-1.04)<0.001Charlson-Deyo comorbidity score<0.0011 vs 00.86 (0.82-0.90)2+ vs 00.72 (0.66-0.79)Grade2<0.001Moderately/Poorly vsWell Differentiated0.91 (0.88-0.95)Clinical N category2<0.001cN1 vs cN00.49 (0.46-0.52)cN2/cN3 vs cN00.41 (0.35-0.47)Multicentric<0.001Yes vs No0.36 (0.34-0.38)Primary treatment by clinical T category2<0.001For cT1 tumorsLong course NET vs primary surgery0.65 (0.51-0.83)NAC vs Primary surgery0.31 (0.24-0.41)Short course NET vs primary surgery0.85 (0.58-1.24)For cT2 tumorsLong course NET vs primary surgery1.51 (1.27-1.79)NAC vs primary surgery1.04 (0.90-1.20)Short course NET vs primary surgery0.53 (0.33-0.85)For cT3/cT4 tumorsLong course NET vs primary surgery2.52 (1.97-3.22)NAC vs primary surgery1.54 (1.27-1.88)Short course NET vs primary surgery0.79 (0.31-2.02)1Model additionally adjusted for year of diagnosis, race, ethnicity, and insurance status.2Unknown level included in the model but not reported Citation Format: Rita A Mukhtar, Tanya L. Hoskin, Elizabeth B. Habermann, Judy C. Boughey. Trends in primary management of invasive lobular carcinoma: An analysis of the National Cancer Database (NCDB) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-13-01.

PURPOSE To determine the sensitivity and specificity of genetic testing criteria for the detection of germline pathogenic variants in women with breast cancer. MATERIALS AND METHODS Women with breast cancer enrolled in a breast cancer registry at a tertiary cancer center between 2000 and 2016 were evaluated for germline pathogenic variants in 9 breast cancer predisposition genes ( ATM , BRCA1, BRCA2, CDH1, CHEK2, NF1, PALB2, PTEN, and TP53). The performance of the National Comprehensive Cancer Network (NCCN) hereditary cancer testing criteria was evaluated relative to testing of all women as recommended by the American Society of Breast Surgeons. RESULTS Of 3,907 women, 1,872 (47.9%) meeting NCCN criteria were more likely to carry a pathogenic variant in 9 predisposition genes compared with women not meeting criteria (9.0% v 3.5%; P < .001). Of those not meeting criteria (n = 2,035), 14 (0.7%) had pathogenic variants in BRCA1 or BRCA2. The sensitivity of NCCN criteria was 70% for 9 predisposition genes and 87% for BRCA1 and BRCA2, with a specificity of 53%. Expansion of the NCCN criteria to include all women diagnosed with breast cancer at ≤ 65 years of age achieved > 90% sensitivity for the 9 predisposition genes and > 98% sensitivity for BRCA1 and BRCA2. CONCLUSION A substantial proportion of women with breast cancer carrying germline pathogenic variants in predisposition genes do not qualify for testing by NCCN criteria. Expansion of NCCN criteria to include all women diagnosed at ≤ 65 years of age improves the sensitivity of the selection criteria without requiring testing of all women with breast cancer.