Nipple-Sparing Mastectomies in Patients over the Age of 60 Years: Factors Associated with Surgical Outcomes

BACKGROUND

Nipple-sparing mastectomy (NSM) outcomes in the elderly have not been well characterized. The goal of this study was to evaluate NSM outcomes in patients over age 60.

PATIENTS AND METHODS

A single-institution retrospective cohort study was performed for NSM patients over the age of 60 from January 2004 to January 2022. Demographic, intraoperative, and postoperative variables were collected.

RESULTS

We identified 136 women who underwent a total of 200 NSMs at a mean age 65.2 years and with mean body mass index of 25. Most (56%) had invasive breast cancer, requiring neoadjuvant chemotherapy in 15%, and 17.5% had radiation prior to NSM. A total of 91% had immediate tissue expander placement. The infection rate was 19%, with 11.5% requiring expander explantation in the follow-up period. In binomial logistic regression analysis, prior radiation increased the odds of any complication by 2.9 (OR 2.93, CI 1.30-6.58, p = 0.009) and increased the odds of infection by 5.7 (OR 5.70, CI 1.95-16.66, p = 0.001), but no associations were seen for other covariates including age, comorbidities, prior chemotherapy, or presence of invasive disease. Diabetes increased the odds of wound breakdown specifically by 9.0 (OR 8.97, CI 2.01-39.92, p = 0.004). Local recurrence was 3% in mean 3.4-year follow-up.

CONCLUSIONS

Our data support NSM in patients over the age of 60 years with acceptable outcomes within the standard of care. Locoregional recurrence was within the cited range of 0-5%, and only diabetes and prior radiation were associated with reconstructive complications. NSM should thus be offered when appropriate regardless of increased age to achieve oncologic and reconstructive goals.

Metabolic Positron Emission Tomography in Breast Cancer

Metabolic PET, most commonly 18F-fluorodeoxyglucose (FDG) PET/computed tomography (CT), has had a major impact on the imaging of breast cancer and can have important clinical applications in appropriate patients. While limited for screening, FDG PET/CT outperforms conventional imaging in locally advanced breast cancer. FDG PET/CT is more sensitive than conventional imaging in assessing treatment response, accurately predicting complete response or nonresponse in early-stage cases. It also aids in determining disease extent and treatment response in the metastatic setting. Further research, including randomized controlled trials with FDG and other metabolic agents such as fluciclovine, is needed for optimal breast cancer imaging.

Impacts of a lead smelter in East Java, Indonesia: degree of contamination, spatial distribution, ecological risk, and health risk assessment of potentially toxic elements in soils

This study investigates the characteristics of potentially toxic elements in soils collected from the vicinity of a lead smelter in East Java, Indonesia. The objective is to assess the impact of the lead smelter on the surrounding soil. The study involves chemical composition analysis, spatial distribution mapping, and potential ecological and health risk assessments. Soil samples were collected from the surface area (0-10 cm) and subsurface (15-30 cm) within radii of 1.5 km, 3 km, and 5 km from the lead smelter. The samples were analyzed for As, Cr, Cu, Ni, Pb, and Zn using energy-dispersive X-ray fluorescence. Principal component analysis (PCA) was performed to identify the sources of potentially toxic elements in the soil. The results indicate severe Pb contamination within a 1.5 km radius of the smelter, with an average contamination factor (Cf) value of 22.0, posing a high potential health risk. The contamination factor indicated that the soils were heavily polluted by As and Pb and moderately polluted by Cu, Ni, and Zn. The results of PCA showed that smelter releases are the main source of potentially toxic element contamination in the soil, accounting for 66.2%. The health risk assessment suggested that the children and adults in the study region were exposed to non-carcinogenic risks caused by As and Pb. Oral ingestion was identified as the primary exposure route impacting health risks. The carcinogenic risk from potentially toxic elements in soil was found to exceed the acceptable level for children and adults in the study region. Therefore, it is necessary for the government to take effective measures, including designing regulations and interventions, and improving lead smelter management to mitigate potential contamination and minimize the impact of lead smelter releases on the surrounding environment, especially to protect human health, particularly that of children.

Abstract P6-05-10: An international survey on invasive lobular breast cancer (ILC) reveals gaps in knowledge and top priority research areas

Background: There is growing awareness of the unique etiology, biology, clinical presentation and progression of Invasive lobular breast cancer (ILC), but additional research is needed to assure translation of findings into management and treatment guidelines. We performed a survey to: 1) analyze the landscape of the current understanding of ILC, and 2) identify consensus research questions on ILC.

Methods: The IRB-approved survey was developed with input from representatives of three major stakeholder groups - breast cancer clinicians/researchers, laboratory-based researchers, and advocates/patients. We fielded the survey from March to May 2022 using targeted email and via social media.

Results: 1,774 participants answered at least one question and 1,310 finished the survey. Participants are from 66 countries from all continents (except Antarctica). Respondents self-identified as clinicians (mostly medical oncologists and surgeons) (N=413), researchers (N=376), and breast cancer patients (1,121), with some belonging to more than one category. 26% of the patients who participated in the survey belong to advocate groups.

Only 46% of clinicians reported being confident in describing the differences between ILC and no special type (NST) (invasive ductal) breast cancer. Knowledge of histology was seen as important (73%), affecting their treatment decisions (51%), and refined treatment guidelines would be valuable for patients with ILC in the future (76%). 85% of clinicians have never powered a clinical trial to allow subset analysis for histological subtypes, but the majority would consider it. 88% would participate in a consortium to conduct clinical trials on ILC. The top two most important research questions were: 1) determining mechanisms of endocrine resistance, and, 2) identifying novel therapeutic targets, repurposing existing drugs and progressing them to clinical trials.

Of the researchers, 48% reported being confident in describing differences between ILC and NST. They reported that ILCs are inadequately presented in large genomic data sets (52%), and that ILC models are insufficient (42%). Only 13% of respondents have inadequate access to tissue or blood from patients with ILC. The top two most important research questions identified by the laboratory researchers overlapped with those identified by the clinicians, i.e. understanding of endocrine resistance and identifying novel drugs that can be tested in clinical trials.

The majority of patients (52%) thought that their health care providers did not explain unique features of ILC, and that in general communication was limited. When asked about top research question, they chose: 1) Improvement of ILC screening/early detection, and, 2) Identifying new and specific imaging tools for ILC.

When comparing top priority topics across six research domains, there was a high degree of consistency, especially among clinicians and researcher, but less so when compared with the breast cancer patients (Table 1).

Conclusion: In summary, we have gathered timely and representative information from an international community of clinicians, researchers, and patients/advocates that we expect will lay the foundation for a community-informed collaborative research agenda, with the goal of improving the management and personalizing treatment for patients with ILC.

Table 1. Ratings by all three stakeholder groups of the most critical and impactful ILC research topics. Top box scores between stakeholder groups were compared using chi-square analysis.

Citation Format: Steffi Oesterreich, Leigh Pate, ADRIAN V. LEE, Rachel C. Jankowitz, Patrick Derksen, Rita Mukhtar, Otto Metzger, Matthew J. Sikora, Christopher Li, Christos Sotiriou, Gary Ulaner, Jorge Reis-Filho, Nancy E Davidson, Karen Van Baelen, Laurie Hutcheson, Siobhan Freeney, Flora Migyanka, Claire Turner, Todd Bear, Christine Desmedt. An international survey on invasive lobular breast cancer (ILC) reveals gaps in knowledge and top priority research areas [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-05-10.

Abstract HER2-14: HER2-14 HER-2 low status in early stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series

Objectives: The concept of human epidermal growth factor receptor 2 (HER2)-low status has been proposed as a potential treatment target for breast cancers previously considered to be HER2-negative. Defined by an immunohistochemistry (IHC) score of 1+ or 2+ and negative fluorescent in situ hybridization (FISH) for HER2, HER2-low status predicts significant clinical benefit from novel therapeutic compounds in recent clinical trials. The prevalence and clinical implications of HER2-low status in patients with early stage invasive lobular carcinoma (ILC) has not been described. We aimed to describe the clinicopathologic features and prevalence of HER2-low status in ILC, and identify any potential differences in clinical outcome. Methods: We evaluated stage I-III ILC tumors from a prospectively maintained institutional database of patients where both IHC and FISH testing for HER2 status was performed as standard clinical care. Tumors were classified as HER2 negative (IHC=0), HER2-low (IHC=1+ or 2+ and negative FISH), or HER2 positive (IHC=3+ or FISH ratio ⇒2). Data were analyzed in Stata 16.1 using chi-squared tests, t-tests, and Cox proportional hazards models for disease free survival (DFS). Results: 666 ILC tumors with available HER2 status were available for analysis. The mean age at diagnosis was 59.8 years (range 21-91). The majority of patients had stage I disease (63.1%) with an average follow up time of 6.7 years (standard deviation [5.4]). Overall, 184 (27.6%) tumors were HER2 negative, 434 (65.1%) were HER2-low, and 48 (7.2%) were HER2 positive. There were no associations between HER2 status and age, menopausal status, body mass index, tumor stage, grade, presence of lymphovascular invasion, or molecular assay results. Hormone receptor status was significantly associated with HER2 status, with HER2 positive tumors significantly less likely to be estrogen receptor (ER) positive than both HER2 negative and HER2-low tumors (89.6% versus 97.3% and 96.8% respectively, p=0.03). HER2-low tumors were also significantly more likely to have progesterone receptor (PR) positivity (86.6% compared to 79.9% of HER2 negative and 72.9% of HER2 positive tumors, p = 0.01). This difference remained significant when comparing just HER2-low to HER2 negative cases (p=0.034). While there were no differences in use of neoadjuvant or adjuvant chemotherapy by HER2 status, HER2-low patients were significantly more likely to undergo mastectomy versus lumpectomy when compared to HER2 negative and HER2 positive patients (53.7% versus 38.0% and 43.8% respectively, p= 0.001). In a multivariable Cox proportional hazards model adjusting for tumor size, number of positive nodes, ER/PR status, and local therapy received, patients with HER2-low status had worse DFS than those with HER2 negative tumors (hazard ratio 2.0, 95% confidence interval 1.0 - 4.1, p=0.05). Conclusions: In this analysis of 666 early stage ILC cases, we found that most tumors were HER2-low, and that those with HER2-low disease were significantly more likely to have PR positive tumors and to undergo mastectomy. When adjusting for these variables, we identified a difference in DFS between HER2 negative and HER2-low early stage ILC. These findings support the contention that HER2-low and HER2 negative disease represent two different clinical entities. Further investigation of the potential benefit of HER2 targeted therapy in ILC, which predominately lacks HER2-amplified disease, is needed to ensure optimal outcomes in this understudied tumor type.

Citation Format: Harriet T. Rothschild, Elle Clelland, Anne Patterson, Julissa Molina-Vega, Mandeep Kaur, Mary Kathryn Abel, W. Fraser Symmans, Christopher J. Schwartz, Rita Mukhtar. HER2-14 HER-2 low status in early stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr HER2-14.

Abstract PD9-08: ImPrint immune signature in 10,000 early-stage breast cancer patients from the real-world FLEX database

BACKGROUND: Immune checkpoint inhibitors in combination with chemotherapy have demonstrated an improvement of pathologic complete response (pCR) in patients with HR-HER2- and MammaPrint (MP) High Risk, HR+HER2- tumors in the I-SPY2 TRIAL. However, not all patients benefit from immune checkpoint blockade and these new agents come with additional financial burden and significant long-lasting side effects such as adrenal insufficiency. Thus, it is imperative to better understand who benefits. Response Predictive Subtypes (RPS) were developed in the I-SPY2 TRIAL using pre-treatment expression data from 987 MP High Risk patients; 39% of HR+HER2- tumors and 63% of HR-HER2- tumors were identified as immune sensitive. In I-SPY2.2, RPS tumor classification uses ImPrint, a 53-gene signature that has been independently validated to predict the likelihood of a pCR with PD1-PDL1 immune checkpoint inhibitors with high sensitivity and specificity. Using a real-world dataset of 10,000 patients enrolled in the FLEX trial, we identified immune sensitive (ImPrint+) patients within immunohistochemistry (IHC) subtypes and within MP and BluePrint (BP) subgroups.

METHODS: FLEX (NCT03053193) is an ongoing registry trial with 97 sites open in the United States and 2 international sites. Patients enrolled in FLEX have early-stage breast cancer and receive standard of care MP testing with or without BP molecular subtyping and consent to clinically annotated full genome data collection. MP is a 70-gene risk of distant recurrence signature that classifies patients as Low Risk or High Risk. MP High Risk can be further stratified into High 1 and High 2, which have demonstrated differences in chemosensitivity and pCR rates in the I-SPY2 TRIAL (NCT01042379). BP, an 80-gene molecular subtyping signature, categorizes patients’ tumors as Luminal-, HER2- or Basal-Type.

RESULTS: Of the 10,021 patients, 9.1% of the FLEX patient population are ImPrint+ and are predicted to have a meaningful pCR rate with immune checkpoint inhibitors. Younger (≤ 50 years) or pre/peri-menopausal patients, patients with larger or node-positive tumors, and patients of Black or Latin race/ethnicity independently had a higher likelihood of having ImPrint+ tumors (Table 1). ImPrint+ tumors were identified in all clinical subtypes by IHC. There is a higher likelihood of ImPrint+ tumors being MP High 2 or BP Basal-Type tumors. Within BP Basal tumors, 74.7% of HR+ and 66.0% of HR- tumors were ImPrint+.

CONCLUSIONS: The focus of immune therapy trials has been on patients with HR-HER2-, MP High Risk patients. Indeed, most patients who are predicted to benefit have MP High 2 or BP Basal-Type tumors, including some HR+ patients, which is consistent with I-SPY2 results. Importantly, this large real-world dataset enables the identification of populations who may benefit from immune therapy outside of traditional clinical trial populations and supports the testing of checkpoint inhibitors in the immune-positive subtype. Younger women and patients of Black or Latin race/ethnicity who typically have more aggressive tumors also have higher proportions of ImPrint+ tumors. Thus, it is critical that these populations be included in clinical trials. This first look at immune sensitivity in over 10,000 FLEX patients with ImPrint generates preliminary data and hypotheses that will be explored in future FLEX substudies, including an analysis of lobular cancers and long-term outcomes in ImPrint+ patients across all races and ages.

Table 1. Clinical characteristics of ImPrint+ and ImPrint- tumors.

Citation Format: Adam M. Brufsky, Midas Kuilman, Rita Mukhtar, Denise M. Wolf, Christina Yau, Joyce O’Shaughnessy, Cathy Graham, Vijayakrishna K. Gadi, Pat Whitworth, Alexander Hindenburg, Ian Grady, Gordon Srkalovic, Kent Hoskins, Ajay Dhakal, Cynthia Ma, Natasha Hunter, Jennifer Crozier, Blanche Mavromatis, Lorenza Mittempergher, Christine Finn, Shraddha Modh, Erin B. Yoder, Patricia Dauer, Andrea Menicucci, Bas van der Baan, William Audeh, Laura J. Esserman. ImPrint immune signature in 10,000 early-stage breast cancer patients from the real-world FLEX database [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD9-08.

Abstract P3-09-01: Characterization of residual disease after neoadjuvant selective estrogen receptor degrader (SERD) therapy using tumor organoids in the I-SPY Endocrine Optimization Protocol (EOP)

Background: Treatment of estrogen receptor (ER)-positive breast cancer with selective estrogen receptor degraders (SERDs) frequently results in the loss or reduction of ER expression. Whether these changes are due to on-target effects of SERDs degrading ER or arise as a mechanism of tumor resistance with associated changes in cellular phenotypes remains unknown. It is critical to distinguish between these possibilities to accurately assess treatment response and determine the most appropriate subsequent therapy. To this end, we created and conducted molecular analyses on patient-derived organoid cultures from post-treatment tissue in patients receiving neoadjuvant SERD therapy for early-stage ER+ breast cancer in the I-SPY2 Endocrine Optimization Protocol (EOP). Methods: The I-SPY2 EOP study is a prospective, randomized substudy within the I-SPY TRIAL testing the oral SERD amcenestrant alone or in combination with letrozole or abemaciclib in stage 2/3 ER+ Her2-negative breast cancer. Enrollment is ongoing, with patients receiving amcenestrant neoadjuvantly for 6 months until the day before surgery. Tumor tissue is collected at baseline, 3 weeks, and at surgery. Organoids were generated from post-treatment surgical samples. Organoid cultures were optimized based on established methods (Dekkers et al., Nature Protocols, 2021) to assess ER levels and activity. Pre- and post-treatment tissue samples were also assessed for ER, PR, Ki67, and GATA3, a luminal marker and transcription factor that is functionally linked with ER, via immunohistochemistry. Results: In 7 patients with both pre- and post-treatment tissue samples including fresh surgical samples for organoid generation, the ER in baseline tumor tissue was >=90% in all patients, PR ranged from 40-90%, and Ki67 ranged from 5-30%. In post-treatment surgical tissue from these cases, ER ranged from 0-30%, PR from 0-50%, Ki67 from < 1%-10%, and GATA3 was positive in 5 of 5 cases tested to-date. The creation of organoids from residual disease at surgery was attempted for these 7 patients, with organoids successfully propagated in 5 cases thus far. 3 of 5 organoid cultures were ready for analysis and in all cases strong ER and PR expression in organoids was observed after culture for > 1 month in the absence of amcenestrant. Detailed gene expression profiling (including Mammaprint/Blueprint) and gene set enrichment analyses (GSEA) to assess for intrinsic breast cancer subtype and ER activity in each sample and corresponding organoid culture are in progress and will be reported with the full dataset. Conclusion: Patient-derived organoid culturing of residual disease after neoadjuvant endocrine therapy is feasible. Neoadjuvant treatment with a SERD can render ER and PR low or absent at the time of surgical resection, which does not necessarily imply the presence of endocrine therapy resistant disease. The use of organoids and additional IHC markers (GATA3) demonstrate that receptor negativity may be an indicator of the drug hitting its target, suggesting ER signaling is still intact. In general, patient-derived tumor organoid cultures modeling residual disease states can be a useful adjunct to existing methods used to monitor the effects of neoadjuvant endocrine therapy and is being explored in the I-SPY EOP trial.

Citation Format: Jennifer Rosenbluth, Christopher J. Schwartz, Tam Binh Bui, Shruti Warhadpande, Pravin Phadatare, Sigal Eini, Michael Bruck, Julissa Molina-Vega, Kami Pullakhandam, Nicole Schindler, Lamorna A. Brown Swigart, Christina Yau, Gillian Hirst, Rita Mukhtar, Karthik V. Giridhar, Olufunmilayo I. Olopade, Kevin Kalinsky, Cheryl A. Ewing, Jasmine M. Wong, Michael D. Alvarado, Laura Van’t Veer, Laura J. Esserman, Jo Chien. Characterization of residual disease after neoadjuvant selective estrogen receptor degrader (SERD) therapy using tumor organoids in the I-SPY Endocrine Optimization Protocol (EOP) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-09-01.

Abstract P2-03-16: Quantifying estrogen and progesterone receptor status in early-stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series

Background: Recent guidelines regarding estrogen (ER) and progesterone (PR) receptor testing from the American Society of Clinical Oncology and College of American Pathologists defined a new reporting category of ER-low positive breast cancer for tumors with 1-10% ER expression by immunohistochemistry (IHC). The clinical implications of ER-low positivity are incompletely understood, especially in invasive lobular carcinoma (ILC), the second most common type of breast cancer. Given the rarity of low-ER positivity in ILC, we evaluated tumor features and outcomes associated with a spectrum of ER/PR positivity in a monoinstitutional ILC cohort. Methods: We analyzed cases of stage I-III ILC with available IHC reports. Based on prior published categories in ILC, we classified ER as low, medium, or high as defined by ER staining of 10–69%, 70–89%, and ≥90% respectively. PR negative, low, and high tumors were defined by 0%, < 20%, or ≥20% staining respectively. We used chi-squared tests, t-tests, and Cox proportional hazards models in Stata 16.1 to evaluate associations between ER/PR categories including clinicopathologic variables and event-free survival (EFS). Results: Of 744 cases, 24 (3.2%) were ER negative and 10 (1.3%) were ER-low positive as defined by 1-10% positive staining. 713 remaining cases had ER positivity ≥ 10% and comprised the cohort categories of ER low, medium, and high for this study (11.2%, 15.0%, and 73.8% respectively). In 751 cases with PR data, 122 (16.2%) were PR negative, 145 (19.4%) were PR low and 483 (64.3%) were PR high. ER high status was significantly associated with older age (mean 56.7, 56.7, and 60.6 years in ER low, medium, and high respectively, p=0.0005). ER low was associated with PR negative and low status (42.3% were PR neg/low and ER low, versus 37.4% with ER medium and 29.9% in ER high, p=0.045), and more likely to have overexpression of HER2 (9.7%, 9.0%, and 2.9% ER low, medium, high, respectively, p=0.002). ER low tumors were more likely to be grade 1 than ER medium or high (41.8%, 29.8% and 24.5% respectively, p=0.025), and have positive surgical margins (39.4%, 35.9% and 23.9% respectively, p=0.002). ER status was not associated with Ki67, stage, body mass index (BMI), lymphovascular invasion, lobular carcinoma in situ (LCIS), pleomorphic histology, local therapy, or chemotherapy use. In contrast, PR high was significantly associated with younger age (57.6 versus 63.5 years in PR low, p< 0.0001). PR low was associated with HER2 overexpression (8.6% versus 3.2% in PR high, p=0.002). PR low cases were more likely to present at higher stages (15.8% stage III versus 10.1% stage III in PR high, p=0.032), to be pleomorphic (16.8% versus 8.2%, p< 0.001), and to receive chemotherapy (30.8% versus 23.1%, p=0.022) but were less likely to have associated LCIS (64.0 versus 74.2%, p=0.004). PR status was not associated with Ki67, BMI, lymphovascular invasion, local therapy, or surgical margins. In a Cox proportional hazards model adjusting for age, stage, grade, pleomorphic histology, and chemotherapy use, ER category was not associated with EFS but both PR negative and PR low status each had significantly worse EFS compared to PR ≥20% (HR 3.5, 95% CI 1.8-6.7, p< 0.001 for PR negative, and HR 2.0, 95% CI 1.1-3.5, p=0.015 for PR low). The estimated cumulative 5-year EFS for patients with ER low, medium, and high tumors was 87.1%, 93.4%, and 90.1% respectively. The estimated cumulative 5-year EFS for patients with PR negative, low, and high tumors was 78.9%, 90.2%, and 92.7% respectively. Conclusions: Using ILC-specific categories for ER expression, we found associations between ER category and clinicopathologic variables but not with EFS. In contrast, PR negative and low status was associated with worse EFS. These findings highlight the importance of exploring the spectrum of ER/PR activity within ILC, a classically strongly hormone receptor-positive tumor type, using more quantitative methods.

Citation Format: Elle Clelland, Harriet T. Rothschild, Anne Patterson, Julissa Molina-Vega, Mandeep Kaur, Mary Kathryn Abel, W. Fraser Symmans, Jo Chien, Christopher J. Schwartz, Rita Mukhtar. Quantifying estrogen and progesterone receptor status in early-stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-03-16.

Abstract LB021: Mechanosensitive hormone signaling promotes mammary progenitor expansion and breast cancer progression

Tissue stem-progenitor cell frequency has been implicated in tumor risk and progression. Tissue-specific factors linking stem-progenitor cell frequency to cancer risk and progression remain ill defined. Using a genetically engineered mouse model that promotes integrin mechanosignaling with syngeneic manipulations, spheroid models, and patient-derived xenografts we determined that a stiff extracellular matrix and high integrin mechanosignaling increase stem-progenitor cell frequency to enhance breast tumor risk and progression. Studies revealed that high integrin-mechanosignaling expands breast epithelial stem-progenitor cell number by potentiating progesterone receptor-dependent RANK signaling. Consistently, we observed that the stiff breast tissue from women with high mammographic density, who exhibit an increased lifetime risk for breast cancer, also have elevated RANK signaling and a high frequency of stem-progenitor epithelial cells. The findings link tissue fibrosis and integrin mechanosignaling to stem-progenitor cell frequency and causally implicate hormone signaling in this phenotype. Accordingly, inhibiting RANK signaling could temper the tumor promoting impact of fibrosis on breast cancer and reduce the elevated breast cancer risk exhibited by women with high mammographic density.

Citation Format: Jason J. Northey, Yoshihiro Yui, Mary-Kate Hayward, Connor Stashko, FuiBoon Kai, Janna Mouw, Dhruv Thakar, Jonathon Lakins, Alastair Ironside, Susan Samson, Rita Mukhtar, E. Shelley Hwang, Valerie Weaver. Mechanosensitive hormone signaling promotes mammary progenitor expansion and breast cancer progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB021.

Abstract OT1-10-02: I-SPY2 endocrine optimization protocol (EOP): A pilot neoadjuvant endocrine therapy study with amcenestrant as monotherapy or in combination with abemacicilib or letrozole in molecularly selected HR+/HER2- clinical stage 2/3 breast cancer

Background: There is no clinical equipoise on the best upfront management of patients with early-stage hormone receptor-positive (HR+)/HER2-negative (HER2-) breast cancer (BC) that is high-risk by clinicopathologic criteria, and low-risk based on molecular profiling. These patients are unlikely to respond to chemotherapy. However, these patients still have risk, often risk of late recurrence, despite standard adjuvant endocrine therapy. Novel endocrine-based strategies that are more effective and tolerable than current standard therapies are needed for this population. Next-generation orally-bioavailable selective estrogen receptor degraders (oSERDs) with improved pharmacokinetic (PK) properties are promising potential therapies for HR+ BC. The oSERD amcenestrant has demonstrated a favorable safety profile and encouraging efficacy in a phase I/II dose escalation and expansion trial for heavily pre-treated patients with HR+ metastatic BC and is an attractive agent for assessment in the neoadjuvant BC setting. The neoadjuvant setting offers a unique opportunity to study novel agents and to assess early biological endpoints. However, one of the challenges in studying endocrine-based strategies in the neoadjuvant setting is the lack of a robust surrogate endpoint to reliably predict response and benefit. The I-SPY2 Endocrine Optimization Protocol (EOP) is a pilot sub-study within the main I-SPY2 TRIAL that will test amcenestrant alone or in combination with abemaciclib or letrozole. EOP will test the feasibility of using the I-SPY2 platform to test novel endocrine-based strategies in the neoadjuvant setting in patients with clinical high-risk, molecular low-risk, HR+/HER2- tumors, and will generate a rich database of imaging, molecular, and pathologic correlative endpoints that may potentially inform the improved assessment of response to neoadjuvant endocrine therapy. Trial Design/Eligibility/Accrual: The I-SPY2 EOP is a prospective, randomized, open-label trial specifically for patients with HR+/HER2-negative MammaPrint (MP) low-risk tumors that are at least 2.5 cm in size. Eligible patients are identified during the screening process for the parent I-SPY2 trial. The planned total accrual for the EOP is 120 patients. Patients are randomized 1:1:1 to one of 3 oral treatment arms: 1) amcenestrant 200 mg daily; 2) amcenestrant 200 mg daily + abemaciclib 150 mg bid; 3) amcenestrant 200 mg daily + letrozole 2.5 mg daily. Patients are treated for 6 months prior to surgery. Premenopausal women must receive concomitant monthly ovarian suppression. Serial breast MRIs, breast biopsies, blood, and patient reported outcomes (PROs) are being collected, and patients will be followed for 10 years for recurrence and survival. Serial dedicated breast PET (dbPET) scans and PKs will be assessed in a subset of patients. Objectives/Statistics: The primary objective of the EOP is to investigate the feasibility of enrolling and treating molecularly-selected patients with early stage HR+/HER2- MP low-risk BC in a randomized neoadjuvant trial using an oral-SERD backbone. Treatment will be determined to be feasible if ≥75% of enrolled patients complete ≥75% of assigned study therapy. Secondary objectives include the safety, tolerability, PROs, and PKs related to amcenestrant +/- abemacilcib and letrozole, as well as the assessment of imaging, pathologic, and molecular correlative endpoints as potential biomarkers of response to neoadjuvant endocrine therapy. Status: This study opened in May 2021. Accrual is ongoing.

Citation Format: A. Jo Chien, Kevin M Kalinsky, Julissa Molina-Vega, Rita Mukhtar, Karthik Giridhar, Olufunmilayo I Olopade, Amrita Basu, Smita M Asare, Paul Henderson, Gillian Hirst, Ruixiao Lu, Ella Jones, Nola Hylton, Lamorna Brown-Swigart, Laura J van 't Veer, Douglas Yee, Ingrid Mayer, Laura J Esserman. I-SPY2 endocrine optimization protocol (EOP): A pilot neoadjuvant endocrine therapy study with amcenestrant as monotherapy or in combination with abemacicilib or letrozole in molecularly selected HR+/HER2- clinical stage 2/3 breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT1-10-02.

O13 BIOLOGIC VERSUS SYNTHETIC MESH IN VENTRAL HERNIA REPAIR: PARTICIPANT-LEVEL ANALYSIS OF TWO RANDOMIZED CONTROLLED TRIALS AT ONE YEAR

Aim

Biologic mesh has been increasingly utilized in complex ventral hernia repair despite limited evidence at low risk of bias supporting its growth. We hypothesized biologic mesh when compared to synthetic mesh would have fewer major complications at one year.

Material and Methods

We performed a participant-level meta-analysis of published randomized controlled trials (RCTs) comparing biologic to synthetic mesh at one year. Primary outcome was major complication (composite of mesh infection, recurrence, reoperation, or death) at one year post-operative. Secondary outcomes included length of index hospital stay, surgical site occurrence, and surgical site infection. Outcomes were assessed using frequentist generalized linear models.

Results

A total of 252 patients from two RCTs were included, 126 patients randomized to the intervention arm of biologic mesh and 126 patients randomized to the control of synthetic mesh. Median follow-up was 15 (12, 27) months. Major complication occurred in 41 (33%) patients randomized to biologic mesh, and 44 (35%) patients randomized to synthetic mesh, (relative risk [RR] 0.91, 95% confidence interval [CI] 0.54-1.55, p-value 0.740). There were 36 total recurrences, 23 (18%) in the biologic arm, and 13 (10%) in the synthetic arm (RR 1.83, 95% CI 0.84-3.99, p-value 0.130). The remainder of outcomes demonstrated no statistically significant differences.

Conclusions

The risk of major complication did not differ between biologic versus synthetic mesh. In patients undergoing ventral hernia repair, there was no clinical benefit with biologic mesh as opposed to synthetic mesh at one year post-operative.

Trigger point injection for post-mastectomy pain: a simple intervention with high rate of long-term relief

Post-mastectomy pain syndrome (PMPS) is a common and often debilitating condition. The syndrome is defined by chest wall pain unresponsive to standard pain medications and the presence of exquisite point tenderness along the inframammary fold at the site of the T4 and T5 cutaneous intercostal nerve branches as they exit from the chest wall. Pressure at the site triggers and reproduces the patient's spontaneous or motion-evoked pain. The likely pathogenesis is neuroma formation after injury to the T4 and T5 intercostal nerves during breast surgery. We assessed the rate of long-term resolution of post-mastectomy pain after trigger point injections (2 mL of 1:1 mixture of 0.5% bupivacaine and 4 mg/mL dexamethasone) to relieve neuropathic pain in a prospective single-arm cohort study. Fifty-two women (aged 31-92) who underwent partial mastectomy with reduction mammoplasty or mastectomy with or without reconstruction, and who presented with PMPS were enrolled at the University of California San Francisco Breast Care Center from August 2010 through April 2018. The primary outcome was a long-term resolution of pain, defined as significant or complete relief of pain for greater than 3 months. A total of 91 trigger points were treated with mean follow-up 43.9 months with a 91.2% (83/91) success rate. Among those with a long-term resolution of pain, 60 trigger points (72.3%) required a single injection to achieve long-lasting relief. Perineural infiltration with bupivacaine and dexamethasone is a safe, simple, and effective treatment for PMPS presenting as trigger point pain along the inframammary fold.

Abstract PD6-08: DCE-MRI derived imaging features for characterizing invasive lobular breast cancer and predicting recurrence-free survival after neoadjuvant therapy

Background With current imaging technologies, assessing response to neoadjuvant chemotherapy (NAC) or neoadjuvant endocrine therapy (NET) remains a challenge for patients with invasive lobular carcinoma (ILC). Therefore, we evaluated imaging features from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) before and after neoadjuvant therapy in a cohort of patients with ILC, including the longest tumor diameter (LD), functional tumor volume (FTV), and peak signal enhancement ratio (SER). FTV is the sum of all image voxels enhancing above a set threshold within a defined region, and has been validated as a predictor of recurrence-free survival (RFS) for breast cancer. SER is a measure of contrast wash-in and wash-out and reflects neovascularity of tumors. We determined whether baseline and post-treatment imaging features differed by type of neoadjuvant therapy and if they were associated with RFS in neoadjuvantly treated ILC regardless of treatment type.

Methods With institutional review board approval, a retrospective analysis of pre- and post-treatment breast DCE-MRI was performed on a cohort of ILC patients receiving neoadjuvant therapy between 1998 and 2017. We compared pre-treatment, post-treatment, and percent reduction (α) in LD, FTV, and peak SER by neoadjuvant treatment type (i.e. NAC or NET) using the Wilcoxon rank-sum test. Univariate t-tests, Chi-squared tests, analysis of variance, and Spearmen’s correlation were used to evaluate associations of clinicopathologic features and treatment type. Univariate and multivariate associations with RFS in the entire neoadjuvantly treated cohort adjusting for treatment type were evaluated using the log-rank test and Cox proportional hazards models.

Results A cohort of 76 patients with pre- and post-treatment MRI were included in this study, of whom 42 (55.3%) received NAC and 34 (44.7%) received NET. The NAC group was significantly younger (55 vs. 60 years, p=0.013), less likely to have stage 1 disease (26.2% vs. 73.5%, p<0.001), and showed a trend of having more human epidermal growth factor 2 receptor-positive (HER2) tumors. The mean follow up time was 4.9 years with no difference between treatment groups. Patients in the NAC group had significantly larger pre-treatment LD and FTV but no difference was found in pre-treatment peak SER between groups. Post-treatment LD, FTV, and peak SER did not differ between treatment groups (Table 1). Those receiving NAC had significantly greater reduction in FTV compared to those receiving NET; αLD and α peak SER did not differ. In a multivariate Cox proportional hazards model including all patients in the cohort, higher pre-treatment peak SER was significantly associated with worse RFS regardless of neoadjuvant treatment type when adjusting for age, stage, receptor subtype, and tumor grade (hazard ratio 1.3, p=0.005, 95% CI 1.1-1.6). Neither LD nor FTV were associated with RFS on multivariate analysis.

ConclusionPre-treatment peak SER measured by MRI may provide prognostic information beyond standard clinicopathologic variables in patients with ILC receiving either neoadjuvant chemotherapy or endocrine therapy. Further evaluation in a larger ILC cohort is needed to validate our initial findings.

Table 1. Comparison of MR imaging features of ILC patients receiving neoadjuvant chemotherapy and neoadjuvant endocrine therapy.Overall(n=76)NAC(n=42)NET(n=34)P-valuePre-treatment (median, IQR)LD (cm)2.7, 1.6-5.44.6, 2.5-71.8, 1.4-3.20.0006FTV (cc)5.8, 2.2-16.48.7, 4.1-24.23.0, 0.9-80.0004SER0.9, 0.8-1.00.9, 0.9-1.00.9, 0.8-1.10.8335Post-treatment (median, IQR)LD (cm)1.1, 0-1.91.0, 0-1.81.3, 0-1.90.6071FTV (cc)0.5, 0.1-1.80.3, 0.1-1.80.7, 0.3-1.80.2196SER0.9, 0.8-1.00.8, 0.8-1.00.9, 0.8-1.10.2321Percent reduction (%)LD44.6, 15.1-10079.6, 33.8-10033.8, 10.1-1000.0958FTV93, 72.5-97.495.8, 90.7-99.172.6, 43.1-94.5<0.0001SER8.5, -11.1-19.710.7, -6.0-21.81.9, -15.1-17.90.3041

Citation Format: Geraldine Tran, Ella Jones, Wen Li, Kelly Fahrner-Scott, David Newitt, Bonnie Joe, Laura Esserman, Nola Hylton, Rita Mukhtar. DCE-MRI derived imaging features for characterizing invasive lobular breast cancer and predicting recurrence-free survival after neoadjuvant therapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD6-08.

Abstract PS1-03: Active surveillance for DCIS: Clinical outcomes at 5.6 years mean follow-up

Introduction:

Standard treatment for ductal carcinoma in situ (DCIS) involves surgical excision with radiation and often endocrine therapy. However, not all DCIS progresses to invasive ductal carcinoma (IDC); thus, surgical intervention may constitute overtreatment for DCIS that has low risk for progressing to IDC. A period of active surveillance (AS) with magnetic resonance imaging (MRI) monitoring may offer the opportunity to stratify lesions with high and low risk for invasion and to avoid overtreatment of DCIS. The purpose of this study was to characterize the outcomes of a cohort of women who elected to go on AS to avoid surgical intervention and to identify whether clinical and imaging features would identify patients who should convert to operative management.

Methods:

The clinicopathologic variables and outcomes of patients with DCIS who prospectively enrolled in MRI monitoring studies between 2002 and 2019 were retrospectively analyzed with IRB approval. We included 64 cases among 63 women who declined standard operative management for DCIS and had at least two breast MRIs. Clinicopathologic data and physician recommendations regarding continuing surveillance versus converting to operative management were recorded from the medical record. Those who had surgical excision showing IDC were considered to have progressed; those with only DCIS at excision or no operative intervention were considered to have stable disease.

Results:

Women in the cohort were an average of 53.6 years (29.8 - 78.9) old, and nearly all cases of DCIS with estrogen receptor (ER) status were ER+ (98.3%). Of the 64 cases in the cohort, 57 received endocrine therapy (89.1%). Average length of time on AS was 2.7 years (.2 – 11.9) with a median of 3 (2 – 18) MRIs performed and mean follow-up time 5.6 years (0.9 – 15.3).

A total of 31 cases (48.4%) eventually had surgical excision while 33 (51.6%) remained on AS. There were 17 cases with IDC at surgery (26.6%). The IDC was an average of 1.5 cm (0.1 – 9.0) and most commonly ER + (88.2%), HER2 + (53.3%), grade 2 (58.9%), and node negative (82.4%). Only 7 women did not take endocrine therapy, but 3 of those women had IDC (42.9%). In 15 of the 17 cases with IDC (88.2%), the physician noted concern for progression in their clinic note and recommended surgical excision. This occurred a mean of 1.9 years (0.2 – 6.5) from the start of AS, with 47%, 67%, and 87% of cases identified within 1, 2 and 3 years from the start of AS. Suspicion of progression was based on an increase in lesion size or prominence on MRI and/or increase in calcifications on mammography. Of those that were identified as good candidates to continue AS with no concern for progression (n = 49), 16 chose to undergo surgical excision (32.7%) and 2 had IDC (4.1%).

Conclusion:

After over a decade of following women who seek alternatives to surgery for DCIS, we have identified clinicopathologic and imaging features that discriminate good candidates for AS and endocrine risk reducing therapy from those best treated with surgical excision. In our cohort of mostly ER+ patients receiving endocrine therapy on AS, over half of the cohort (51.6%) avoided surgical intervention. Her2 status, Oncotype DCIS, and Mammaprint scores of IDC is in process and will be presented. Our data support the study of AS as a method to stratify the risk of IDC and avoid overtreatment. We will present a personalized AS algorithm (based on biology and imaging) that we intend to prospectively test in the ATHENA network and NCI funded MCL consortium.

Table 1: Cohort CharacteristicsFull Cohort (n=64)No evidence of IDC (n=47)IDC at surgery (n=17)Age at Diagnosis (years)53.6 (29.8 - 78.9)52.9 (29.8 - 74.5)55.5 (41.9 - 78.9)Time on AS (years)2.7 (.2 - 11.9)2.8 (.2 - 11.9)2.2 (.3 -5.9)Follow-Up (years)5.6 (0.9 - 15.3)Menopausal StatusPremenopausal26 (40.6%)22 (46.8%)4 (23.5%)Postmenopausal35 (54.7%)24 (51.1%)11 (64.7%)Unknown3 (4.7%)1 (2.1%)2 (11.8%)Breast CompositionFatty4 (6.3%)3 (6.4%)1 (5.9%)Scattered14 (21.9%)9 (19.1%)5 (29.4%)Heterogeneous27 (42.2%)19 (40.4%)8 (47.1%)Extreme17 (26.5%)14 (29.8%)3 (17.6%)Unknown2 (3.1%)2 (4.3%)0 (0.0%)ER StatusPositive57 (89.1%)41 (87.2%)16 (94.1%)Negative1 (1.6%)0 (0.0%)1 (5.9%)Unknown6 (9.3%)6 (12.8%)0 (0.0%)PR StatusPositive50 (78.1%)36 (76.6%)14 (82.3%)Negative5 (7.8%)3 (6.4%)2 (11.8%)Unknown9 (14.1%)8 (17.0%)1 (5.9%)GradeHigh20 (31.3%)15 (31.8%)5 (29.4%)Intermediate32 (50.0%)21 (44.6%)11 (64.7%)Low10 (15.6%)9 (19.1%)1 (5.9%)Unknown2 (3.1%)2 (28.5%)0 (0.0%Hormone TherapyYes57 (89.1%)43 (91.5%)14 (82.4%)No7 (10.9%)4 (8.5%)3 (17.6%)

Citation Format: Case Brabham, Rita Mukhtar, April Liang, Paul Kim, Gillian Hirst, Amrita Basu, Heather Greenwood, Rita Freimanis, Alexander Borowsky, Shelley Hwang, Rick Baehner, Gregor Krings, Nola Hylton, Laura Esserman. Active surveillance for DCIS: Clinical outcomes at 5.6 years mean follow-up [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-03.

Abstract PD5-01: Magnetic resonance imaging insights from an active surveillance cohort of women with DCIS

Purpose: Standard treatment for ductal carcinoma in situ (DCIS) involves surgical excision usually with radiation therapy or mastectomy and often endocrine therapy, treatments that are the same as for invasive cancer (IDC). It is clear, however that not all patients with DCIS will develop IDC and so the question is who benefits from early surgical intervention? Active Surveillance (AS) with endocrine risk reduction presents an opportunity to improve outcomes by identifying those lesions that can be managed with endocrine therapy alone without immediate surgical intervention. An active surveillance cohort of women who chose not to have surgery at diagnosis were followed with serial MRIs to identify the imaging features associated with successful AS and those with IDC. Methods: Patients with DCIS were enrolled in MRI surveillance studies between 2002 and 2019 and analyzed retrospectively with IRB approval. Per medical record review, these patients sought to avoid surgical intervention. Inclusion criteria included at least two breast MRIs performed for purposes of surveillance. The final cohort of patients included 64 cases with at least two breast MRIs, with 27 patients having more than 4 MRIs. All breast MRIs consisted of routine sequences, including both pre and post IV contrast images with at least 2 post-contrast time points. Lesion conspicuity, change in lesion, background parenchymal enhancement (BPE), change in BPE, and likelihood of invasive cancer at each MRI timepoint, were subjectively measured independently by two breast radiologists. A Likert scale was used to grade each imaging feature. Radiologists were blinded to the clinical outcome of whether the patient had IDC at surgery or not. Input variables included all imaging features collected and classification trees were trained and bootstrapped on 90% of the data using recursive partitioning to distinguish imaging features predictive of clinical outcome. Proportionality tests were conducted to test whether IDC was associated with age, menopausal status, and breast composition among other clinical variables.Results: Women in the cohort had a mean age of 53.6 years (range 29.8 to 78.9). 98.3% were HR+. Of the 64 cases in the cohort, 57 received endocrine therapy (89.1%). A total of 31 cases (48.4%) eventually had surgical excision and 33 (51.6%) remained on AS. At surgery, 17 patients had IDC (26.6%). Classification trees revealed that the most distinguishing features in the model correlating with IDC were if the lesion was distinct from background at MRI timepoint 1, an increase in BPE between MRI timepoints 1 and 2, and an increase in the lesion size or conspicuity between MRI timepoints 1 and 2. At diagnosis, 56.3% demonstrated a more diffuse pattern of enhancement where the DCIS lesion was not distinguishable above background. Of those with lesions that did not stand out above background at diagnosis and whose BPE did not increase, only 1 of 31 patients developed IDC (3%) with mean follow up of 4.62 years. Patients with IDC were proportionately older (>60) and post-menopausal (73% with IDC were postmenopausal), although only 57% were postmenopausal at diagnosis. Other variables such as breast composition were not enriched in either the IDC versus the non-IDC population. Conclusion: Our study suggests that imaging markers such as BPE and conspicuity of lesion enhancement may provide information to better understand and stratify the risk of DCIS and avoid overtreatment. Importantly, MRI may provide insight as to when a diagnosis of DCIS is more likely to be a global risk factor amenable to endocrine risk reduction, versus a lesion best treated with surgical excision. Pathology correlation is underway. We are currently developing methods to improve reproducibility and harmonization between radiologists, and performance on a validation set will be presented.

Citation Format: Heather Greenwood, Rita Freimanis, Case Brabham, Rita Mukhtar, Gillian Hirst, Paul Kim, April Liang, Laura Esserman, Nola Hylton, Amrita Basu. Magnetic resonance imaging insights from an active surveillance cohort of women with DCIS [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD5-01.

Abstract PS17-05: Relationship between body mass index and tumor subtype by menopausal status: An analysis in women with lobular carcinoma of the breast

Background: Invasive lobular carcinoma (ILC) is the second most common type of breast cancer and is primarily estrogen receptor (ER)-positive. Compared to invasive ductal carcinoma, ILC is more strongly associated with risk factors that modulate sex steroid hormones, including obesity and use of hormone replacement therapy. Studies also suggest that body mass index (BMI) and metabolic syndrome may impact the molecular characteristics of ILC. We evaluated the relationship between BMI, metabolic syndrome, and tumor characteristics by menopausal status in a single institution cohort of women with newly diagnosed ILC.

Methods: We retrospectively evaluated ILC cases from an institutional database of patients treated between 1996 and 2020. We excluded cases with mixed ILC/IDC histology, and those with triple negative or human epidermal growth factor-2 overexpressing disease. BMI was calculated as (weight kg)/(height m)^2 and was evaluated continuously and categorically with 20-24.9 as normal weight, 25-30 as overweight, and >30 as obese. Metabolic syndrome was defined as having any 3 of the following 5 factors: obesity, hypertension, hypercholesterolemia, hypertriglyceridemia, or diabetes mellitus. Oncotype Dx Recurrence Scores (RS) were recorded in the subset for whom scores had been obtained clinically. Data were analyzed in Stata 14.2.

Results: Of the 481 ILC cases studied, 147 (30.5%) were pre-menopausal at diagnosis, while 334 (69.5%) were post-menopausal, with mean ages of 48 and 64.9 years (p<0.0001). Most tumors (79.5%) were both ER-positive and progesterone receptor (PR)-positive. Post-menopausal women had significantly more ER-positive/PR-negative ILC than premenopausal women (25.3% vs 9.9%, p<0.001), were more likely to have a BMI in the overweight/obese category (53.6% vs 40.1%, p=0.016), and were more likely to have metabolic syndrome (21.9% vs 6.8%, p<0.001). Of the 143 cases with an Oncotype RS, 69.9% were intermediate, 21.7% were low, and 8.4% were high risk. Post-menopausal women had significantly higher RS than premenopausal women when RS was treated as a continuous variable (16.9 vs 13.8, p=0.007). Among postmenopausal women, overweight/obesity status was associated with lower RS while those with normal weight had a greater proportion of high RS tumors (p=0.027). There was no association between BMI and RS in the pre-menopausal population. Similarly, there was no association between metabolic syndrome and tumor subtype in either group.

Conclusions: In this cohort of women with ER-positive pure ILC, we found that post-menopausal ILC had higher rates of overweight/obesity, metabolic syndrome, and numerically higher RS than pre-menopausal ILC. However, within the post-menopausal group, higher BMI was anti-correlated with RS whereas BMI had no impact on pre-menopausal ILC RS. Since obesity is associated with worse outcomes for breast cancer, these findings are unexpected and raise the possibility that the hormonal pathogenesis and estrogenic drive behind ILC differs in pre- vs post-menopausal women, consistent with their different PR positivity rates, possibly due to the more local production of estrogen from higher breast adiposity in post-menopausal women relative to the greater systemic ovarian production of estrogen in pre-menopausal women. These findings have potential implications for both ILC prevention and adjuvant therapy strategies.

CharacteristicsPremenopausal (n=147)Postmenopausal (n=334)P valueAge, mean (SD)48 (5.5)64.9 (9.7)<0.0001Body mass index0.016BMI<25, n (%)88 (59.9%)155 (46.4%)BMI 25-30, n (%)39 (26.5%)105 (31.4%)BMI>30, n (%)20 (13.6%)74 (22.2%)Metabolic syndrome present, n (%)10 (6.8%)73 (21.9%)<0.001ILC StageNSI, n (%)86 (58.9%)224 (68.3%)II, n (%)40 (27.4%)61 (18.6%)III, n (%)20 (13.7%)43 (13.1%)ILC GradeNS1, n (%)49 (34.3%)93 (28.3%)2, n (%)88 (61.5%)222 (67.5%)3, n (%)6 (4.2%)14 (4.2%)Hormone Receptor Status<0.001ER+/PR+128 (90.1%)236 (74.7%)ER+/PR-14 (9.9%)80 (25.3%)21-gene Recurrence Score in women with BMI<250.020Low, n (%)10 (25%)2 (6%)Intermediate, n (%)28 (70%)24 (72.7%)High, n (%)2 (5%)7 (21.3%)21-gene Recurrence Score in women with BMI>25NSLow, n (%)6 (28.5%)11 (26.8%)Intermediate, n (%)15 (71.5%)27 (65.9%)High, n (%)0 (0%)3 (7.3%)SD, standard deviation, NS, not significant.

Citation Format: Harriet Rothschild, Laura Esserman, Christopher Benz, Rita Mukhtar. Relationship between body mass index and tumor subtype by menopausal status: An analysis in women with lobular carcinoma of the breast [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS17-05.

Applications of 3D printing in breast cancer management

Three-dimensional (3D) printing is a method by which two-dimensional (2D) virtual data is converted to 3D objects by depositing various raw materials into successive layers. Even though the technology was invented almost 40 years ago, a rapid expansion in medical applications of 3D printing has only been observed in the last few years. 3D printing has been applied in almost every subspecialty of medicine for pre-surgical planning, production of patient-specific surgical devices, simulation, and training. While there are multiple review articles describing utilization of 3D printing in various disciplines, there is paucity of literature addressing applications of 3D printing in breast cancer management. Herein, we review the current applications of 3D printing in breast cancer management and discuss the potential impact on future practices.

Abstract P5-08-05: Risk of subsequent events after initial diagnosis of ductal carcinoma in situ - A large multi-center registry study

Introduction: Ductal carcinoma in situ (DCIS) is a pre-malignant lesion but 14-53% will not progress to an invasive cancer. Large, well characterized DCIS datasets with long term follow up are sparse, and there is uncertainty regarding the long term effects of various treatment modalities on subsequent breast events (SBE). Here, we analyze trends identified in the SBE rates from patients treated at two large academic breast care centers in California, UCSF and UCSD.

Methods: Institutional Cancer Registries were used to collect demographic, clinical, imaging and pathologic data. Patients aged 18 years and older without any prior history of breast disease whose first diagnosed breast neoplasm was DCIS and who had at least 6 months of follow up were included. Only SBE beyond 6 months after initial diagnosis were included. All mastectomy types and associated adjuvant treatment were grouped. All patients not undergoing surgery were grouped. Differences between patients in the various treatment groups were assessed using χ2, Student’s t-test, and one-way ANOVA. Poisson regression was used to compare differences in SBE rates between treatment groups. For analysis, follow up times were divided into three 5 years periods (0-5, 6-10, 11-15 years) after initial DCIS diagnosis.

Results: 2730 patients - 1575 (57.7%) at UCSF and 1155 (42.3%) at UCSD - were diagnosed between 1985 and 2017 and included in the study. 1910 (70.0%) underwent breast conserving surgery (BCS), 672 (24.6 %) had mastectomy, 144 (5.3%) did not have surgery, and 4 (0.1%) had missing surgery status. 623 (22.8%) received adjuvant endocrine therapy (ET), 2081 (76.2%) did not and 26 (1.0%) had missing adjuvant endocrine therapy status. 1092 (40.0%) received adjuvant radiation therapy (RT), 1619 (59.3%) did not and 19 (0.7%) had unknown radiation therapy status. Median follow up time for all patients was 7.9 years. 305 patients were diagnosed with SBE. Of these, 144 (47.2%) were in situ and 147 (48.2%) were invasive including 16 (5.2%) metastatic lesions, and 14 (4.6%) had missing invasiveness. Of the 289 patients who did not have a metastatic second lesion, 176 (60.9%) SBE were ipsilateral, 88 (30.4%) were contralateral, and 25 (8.7%) had missing SBE laterality. The overall incidence (i) for any SBE over the entire study period was 1.4%/yr. Compared to women who were treated with BCS alone (N=642, i=2.14%/yr, 95% CI 1.76-2.51), SBE rates were lower in women undergoing BCS with RT (N=719, i=1.13%/yr, 95% CI 0.87-1.40, p<0.001), BCS with RT and ET (N=356, i=0.63%/yr, 95% CI 0.30-0.97, P<0.001), and mastectomy (N=672, i=1.00%/yr, 95% CI 0.75-1.25, p<0.001) but were not significantly different for patients undergoing BCS with ET (N=159, i=2.25%/yr, 95% CI 1.35-3.15, p=0.813). Within the first 5 years of diagnosis, mastectomy, BCS with RT, and BCS with RT and ET all lowered the SBE rate of ipsilateral in situ and invasive SBE (p<0.05, in each case). In contrast, no treatment modalities impacted the rate of contralateral SBE rate during any of the time periods. Importantly, the majority of patients, even with BCS alone never had a subsequent event and only 147 had an invasive event overall.

Conclusion: This large two-center registry study reveals that the rate of invasive and in situ SBE after an initial DCIS diagnosis are comparable. The effect of each treatment modality on SBE incidence rates are consistent with other published studies, with the notable exception of BCS and ET which requires deeper investigation. As expected, local treatment affects mostly ipsilateral events within the first 5 years after initial diagnosis, without impacting the rate of contralateral SBE. Complementary molecular and cellular profiling of selected specimens are underway to help build a more precise BSE risk model and prevent overtreatment.

Citation Format: Thomas O'Keefe, Christina Yau, Eliza Jeong, Emma Iaconetti, Paul Kim, Ann Griffin, Joseph McGuire, Rita Mukhtar, Laura Esserman, Olivier Harismendy, Gillian L. Hirst. Risk of subsequent events after initial diagnosis of ductal carcinoma in situ - A large multi-center registry study [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 P5-08-05.

Functional Status and Survival After Breast Cancer Surgery in Nursing Home Residents

Importance

Breast cancer surgery, the most common cancer operation performed in nursing home residents, is viewed as a low-risk surgical intervention. However, outcomes in patients with high functional dependence and limited life expectancy are poorly understood.

Objective

To assess the overall survival and functional status changes after breast cancer surgery in female nursing home residents stratified by surgery type.

Design, Setting, and Participants

This study used Medicare claims from 2003 to 2013 to identify 5969 US nursing home residents who underwent inpatient breast cancer surgery. Using the Minimum Data Set Activities of Daily Living (MDS-ADL) summary score, this study examined preoperative and postoperative function and identified patient characteristics associated with 30-day and 1-year mortality and 1-year functional decline after surgery. Cox proportional hazards regression was used to estimate unadjusted and adjusted hazard ratios (HRs) of mortality. Fine-Gray competing risks regression was used to estimate unadjusted and adjusted subhazard ratios (sHRs) of functional decline. Statistical analysis was performed from January 2016 to January 2018.

Main Outcomes and Measures

Functional status and death.

Results

From 2003 to 2013, a total of 5969 female nursing home residents (mean [SD] age, 82 [7] years; 4960 [83.1%] white) underwent breast cancer surgery: 666 (11.2%) underwent lumpectomy, 1642 (27.5%) underwent mastectomy, and 3661 (61.3%) underwent lumpectomy or mastectomy with axillary lymph node dissection (ALND). The 30-day mortality rates were 8% after lumpectomy, 4% after mastectomy, and 2% after ALND. The 1-year mortality rates were 41% after lumpectomy, 30% after mastectomy, and 29% after ALND. Among 1-year survivors, the functional decline rate was 56% to 60%. The mean MDS-ADL score increased (signifying greater dependency) by 3 points for lumpectomy, 4 points for mastectomy, and 5 points for ALND. In multivariate analysis, poor baseline MDS-ADL score (range, 20-28) was associated with a higher 1-year mortality risk (lumpectomy: HR, 1.92 [95% CI, 1.23-3.00], P = .004; mastectomy: HR, 1.80 [95% CI, 1.35-2.39], P < .001; and ALND: HR, 1.77 [95% CI, 1.46-2.15], P < .001). After multivariate adjustment, preoperative decline in MDS-ADL score (lumpectomy: sHR, 1.59 [95% CI, 1.25-2.03], P < .001; mastectomy: sHR, 1.79; [95% CI, 1.52-2.09], P < .001; and ALND: sHR, 1.72 [95% CI, 1.56-1.91], P < .001) and cognitive impairment (lumpectomy: sHR, 1.27 [95% CI, 1.03-1.56], P = .02; mastectomy: sHR, 1.26 [95% CI, 1.09-1.45], P = .002; and ALND: sHR, 1.14 [95% CI, 1.04-1.24], P = .003) were significantly associated with 1-year functional decline across all breast cancer surgery groups.

Conclusions and Relevance

For female nursing home residents who underwent breast cancer surgery, 30-day mortality and survival as well as 1-year mortality and functional decline were high. The 1-year survivors had significant functional decline. This study's findings suggest that this information should be incorporated into collaborative surgical decision-making processes.

Abstract P4-11-01: A simple intervention for long-term relief of chronic post mastectomy pain

Background: Post-mastectomy pain syndrome (PMPS) is a common and often debilitating condition. One common cause likely results from injury to the T4 and T5 sensory nerves during breast surgery, with resulting neuroma formation. It manifests as a pain syndrome diagnosed by “trigger points” that reproduce exquisite pain upon palpation. Pain specialists have found a combination of corticosteroids and local anaesthetic given through perineural infiltration, at other sites, effective in alleviating these neuromas or trigger points. Utilizing this principle, we initiated a quality improvement project to treat PMPS. This perineural injection led to remarkable, long-lasting relief of the first few patients, we therefore continued treating patients with clinical symptoms suggestive of a neuroma. We report on long-term pain relief after trigger point injections (TPI) for women with PMPS.

Methods: An observational cohort study of women with PMPS and clinical evidence of neuroma was undertaken. Patients were examined by breast surgeons at a single institution. We injected a 2mL mixture of equal parts 0.5% bupivacaine and 4 mg/mL dexamethasone into each trigger point. Demographics, type of breast and axillary surgery, duration of pain, history of surgical complications, adjuvant radiotherapy, number of injections required, location of trigger points and dates of injection were obtained from the electronic medical record. Patients were surveyed via telephone interview for long-term resolution of pain. Descriptive statistics are reported, univariate and bivariate analyses were conducted using Stata 12 (College Station, TX).

Results: We identified 89 trigger points on 61 breasts in 53 patients with PMPS. Patient age ranged from 30-92 years. Mean number of surgeries prior to injection was 2.2 (range 1-8). In this cohort, we found mastectomy was the most frequent surgical procedure preceding the development of a neuroma (41 breasts), followed by reduction mammoplasty with or without concurrent partial mastectomy (16 breasts), and least frequently lumpectomy alone (4 breasts). The time from the onset of neuropathic pain to the first trigger point injection varied from as early as 1 week post-operatively to 132 months (mean 22.2 months). Effectiveness of the TPI was assessed by physical examination immediately (1-3 minutes) after the injection, then with telephone interview (at &gt;/=3 months post TPI). All 53 patients had long-term follow-up data (≥3 months). Long-term relief was achieved in 84 of 89 trigger points (94.4%) or 54 of 61 breasts (88.5%). Trigger point injections were well tolerated by all patients and no complications were reported.

Discussion: Perineural infiltration with bupivacaine and dexamethasone is a safe, simple, and effective treatment option for PMPS with an associated trigger point. Our data suggest this significant problem can easily be resolved in an outpatient setting. All breast specialists should inquire about the presence of symptoms consistent with PMPS and understand the value of intervention to eliminate neuropathic pain. This technique should be added to the armamentarium of all surgeons who perform breast surgery.

Citation Format: Keane HJ, Khoury AL, Hosseini A, Varghese FP, Mukhtar R, Eder SE, Wong J, Esserman LJ. A simple intervention for long-term relief of chronic post mastectomy pain [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-11-01.

Abstract PD4-04: Role of breast MRI in predicting pathologically negative nodes after neoadjuvant chemotherapy in cN0 patients in the I-SPY2 trial

Background

In clinically node-negative (cN0) breast cancer patients with triple negative (TN) and HER2+ disease and breast pathological complete response (breast pCR), low rates of nodal positivity after neoadjuvant chemotherapy (NAC) have been demonstrated. In these patients, the omission of surgical axillary staging has been proposed. However, this information is not routinely known preoperatively. We aimed to validate the correlation between pathologic breast response and pathologic nodal status, and evaluate the relationship between response of the breast tumor on MRI and pathologic nodal status after NAC in cN0 patients in the I-SPY2 trial.

Methods

We identified all patients with cT1-4 cN0 breast cancer prior to NAC from graduated arms of the I-SPY2 trial, a prospective neoadjuvant chemotherapy trial. Absence of residual disease post-NAC was defined as longest diameter (LD) of 0 mm on MRI. Breast pCR was defined as the absence of invasive tumor in the breast at surgery. Associations between ypN0 and patient, MRI, and tumor characteristics were assessed using chi-square tests and univariate regression.

Results

Of 365 cT1-4 cN0 patients included, 128 had HR+/HER2- tumors (35%), 60 HR+/HER2+ tumors (16%), 34 HR-/HER2+ tumors (9%) and 143 TN tumors (39%). Overall, 283 patients (78%) were ypN0 after NAC and 152 patients (42%) had a breast pCR. ypN0 rate was higher in patients with a breast pCR than those with residual disease (93% vs 66%, p&lt;0.001). Patients with HR-/HER2+ and TN tumors were more likely to be ypN0 (97% and 87% respectively) than patients with HR+/HER2- and HR+/HER2+ disease (66% and 71% respectively, p&lt;0.001). Other characteristics associated with ypN0 were tumor grade (grade I 57%, grade II 66%, grade III 84%; p=0.002), MammaPrint Classification (High Risk 1 68% and High Risk 2 87%; p&lt;0.001) and absence of residual tumor in the breast on MRI (87% vs 72% in patients with evidence of tumor on MRI post-NAC/pre-surgery; p=0.003).

In patients with HR-/HER2+, HR+/HER2+, HR-/HER2+ or TN disease and a breast pCR, ypN0 rate was respectively 82%, 96%, 96% and 97% (table 1). In patients with HR+/HER2-, HR+/HER2+, HR-/HER2+ or TN disease and with no evidence of residual disease in the breast on MRI, rate of ypN0 was 71%, 80%, 94% and 96% respectively.

Conclusion

In cT1-4 cN0 breast cancer patients with HR+/HER2+, HR-/HER2+ and TN tumors and a breast pCR, ypN0 rates after NAC are extremely high. In patients with HR-/HER2+ and TN tumors with no residual breast disease on MRI after NAC and pre-surgery, ypN0 rates are high enough to consider omission of axillary surgery. In patients with HR+ tumors, MRI is unsufficiently predictive for pathological response and can therefore not be used to select ypN0 patients. Research on the prediction of ypN0 in cN+ I-SPY2 patients is ongoing.

Nodal status in patients with pCR and absence of residual disease on MRI Number of positive nodesBreast Cancer Subtype0123AllBreast pCR     HR+/HER2-27(82)2(6)4(12)033(100)HR+/HER2+24(96)01(4)025(100)HR-/HER2+24(96)1(4)0025(100)TN67(97)2(3)0069(100)Absence of residual disease on MRI     HR+/HER2-24(71)7(21)3(9)034(100)HR+/HER2+16(80)3(15)01(5)20(100)HR-/HER2+15(94)1(6)0016(100)TN54(96)2(4)0056(100)

Citation Format: van der Noordaa ME, Esserman L, Yau C, Mukhtar R, Price E, Hylton N, Abe H, Wolverton D, Crane EP, Ward KA, Nelson M, Niell BL, Oh K, Brandt KR, Bang DH, Ojeda-Fournier H, Eghtedari M, Sheth PA, Bernreuter WK, Umphrey H, Rosen MA, Dogan B, Yang W, Joe B, van 't Veer L, Hirst G, Lancaster R, Wallace A, Alvaredo M, Symmans F, Asare S, Boughey JC, I-SPY2 Consortium. Role of breast MRI in predicting pathologically negative nodes after neoadjuvant chemotherapy in cN0 patients in the I-SPY2 trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD4-04.

Abstract P6-01-04: Initial experience of dedicated breast PET imaging of ER+ breast cancers using [F-18]fluoroestradiol

Introduction: Breast cancer is a heterogeneous disease encompassing distinct subtypes with variable treatment response, relapse risk and overall prognosis. The majority of breast cancers are estrogen receptor-positive (ER+). While neoadjuvant endocrine therapy trials have been proposed to better identify therapeutic approaches for ER+ breast cancer, accurate quantification of the ER biomarker is necessary to assess the primary tumor and its likelihood of response to treatment.

Dedicated breast positron emission tomography (dbPET) is an emerging technology with a high spatial resolution that enables detection of sub-centimeter lesions and depiction of intratumoral heterogeneity. In this study, we report our initial experience with [F-18]fluoroestradiol (FES) dbPET in assessing ER+ primary breast cancers.

Materials and Methods: In an IRB-approved protocol, patients with biopsy-confirmed ER+ breast cancers were imaged with dbPET (MAMMI, OncoVision, Valencia, Spain) as a companion diagnostic tool to standard breast MRI. A dose of 5 mCi of FES was administered and patients were imaged in the prone position at 45 min post-injection. As part of routine clinical care, MR images were reviewed by a certified breast radiologist experienced in breast MRI. DbPET was reviewed by a radiologist specialized in nuclear imaging.

Results: Five patients with ER+ breast cancers were imaged. Patient ages ranged from 33 to 64. Two patients with infiltrating lobular carcinomas measuring up to 6.7 cm and 5.3 cm at MRI demonstrated corresponding FES tumor-to-normal maximum standard uptake value (SUVmax) ratio at 4.81 and 2.49 respectively. A third patient demonstrated multifocal FES uptake corresponding to multifocal invasive ductal carcinoma and ductal carcinoma in situ with disease foci ranging from 9-13 mm. In this patient, the more posterior disease foci seen on MRI were excluded from the field of view of dbPET. One patient demonstrated an absence of FES uptake in her 3.4 cm infiltrating ductal carcinoma, which was due to estrogen receptor blockade from the recent administration of tamoxifen for a fertility preservation procedure. The final patient had metastatic cervical and axillary lymphadenopathy secondary to a breast primary that was occult on mammography and MRI. FES-dbPET also showed no corresponding uptake in the ipsilateral breast, possibly due to the small size of the primary lesion and/or low tumor to background uptake ratio.

Conclusions: FES-dbPET imaging has potential as a diagnostic tool that is complementary to MRI in characterizing ER+ primary breast cancers. Limitations include variations of FES uptake in different ER+ breast cancer diseases and exclusion of posterior breast tissue near the chest wall and the axillary regions. However, FES-dbPET has a high potential for clinical utility, especially in measuring response to neoadjuvant endocrine treatment. Further development to improve the dbPET field of view and studies with a larger cohort of ER+ breast cancer patients are therefore warranted.

Citation Format: Jones EF, Ray KM, Mukhtar R, Li W, Franc BL, Esserman LJ, Joe BN, Pampaloni MH, Hylton NM. Initial experience of dedicated breast PET imaging of ER+ breast cancers using [F-18]fluoroestradiol [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-01-04.

Breast tumor location in BRCA mutation carriers and implications for prevention

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Background: Although pathogenic mutations in the BRCA gene are known to confer a high risk of breast cancer, close to 65% of mutation carriers do not opt for prophylactic mastectomy. These women are managed with intense screening, which does not aid in prevention. Breast reduction mammoplasty is a surgical technique shown to reduce breast cancer risk (0.39-0.61 relative risk reduction), and can be modified to target specific areas of the breast. Given that most sporadic breast cancers involve the upper outer quadrant, we wondered if a majority of tumors in BRCA mutation carriers would also be confined to one quadrant, or if they would be equally distributed throughout the breast given the high baseline risk present. Identifying a particularly high risk area of the breast could potentially allow for the use of targeted cosmetic mammoplasty as a novel method of risk reduction. Methods: We reviewed imaging reports on 103 consecutive patients with BRCA mutations and invasive breast cancer, and categorized tumor location by quadrant. Tumors spanning > 1 quadrant were classified as being in both. Bilateral cancers were counted separately. Categorical variables were compared with the chi-squared test. Results: Mean age at breast cancer diagnosis was 44 years. Mean tumor size was 2.2 cm (0.1-7cm) with mean distance from the nipple of 4.8 cm (1-12 cm). 92% of tumors were invasive ductal carcinoma, 46% were hormone receptor positive, 10% Her2 positive, and 44% triple negative. 70% of the tumors were unicentric. Tumors were significantly more likely to be in the upper outer quadrant (54%, with the other quadrants having 11-17% of tumors respectively) whether or not multicentric tumors were included in the analysis (p < 0.00001). Her2 positive tumors were more likely to be multicentric than other subtypes (p = 0.021). Conclusions: More than half of breast cancers in BRCA mutation carriers form in the upper outer quadrant, suggesting that breast reduction mammoplasty targeting removal of the upper outer quadrant could significantly reduce breast cancer risk. For those women who choose not to have prophylactic mastectomies or are not yet ready, these data support an intermediate step to help decrease breast cancer risk, which warrants further study.

Characterizing the immune microenvironment in high-risk ductal carcinoma in situ of the breast

PURPOSE

The recent increase in the incidence of ductal carcinoma in situ (DCIS) has sparked debate over the classification and treatment of this disease. Although DCIS is considered a precursor lesion to invasive breast cancer, some DCIS may have more or less risk than is realized. In this study, we characterized the immune microenvironment in DCIS to determine if immune infiltrates are predictive of recurrence.

METHODS

Fifty-two cases of high-grade DCIS (HG-DCIS), enriched for large lesions and a history of recurrence, were age matched with 65 cases of non-high-grade DCIS (nHG-DCIS). Immune infiltrates were characterized by single- or dual-color staining of FFPE sections for the following antigens: CD4, CD8, CD20, FoxP3, CD68, CD115, Mac387, MRC1, HLA-DR, and PCNA. Nuance multispectral imaging software was used for image acquisition. Protocols for automated image analysis were developed using CellProfiler. Immune cell populations associated with risk of recurrence were identified using classification and regression tree analysis.

RESULTS

HG-DCIS had significantly higher percentages of FoxP3⁺ cells, CD68⁺ and CD68⁺PCNA⁺ macrophages, HLA-DR⁺ cells, CD4⁺ T cells, CD20⁺ B cells, and total tumor infiltrating lymphocytes compared to nHG-DCIS. A classification tree, generated from 16 immune cell populations and 8 clinical parameters, identified three immune cell populations associated with risk of recurrence: CD8⁺HLADR⁺ T cells, CD8⁺HLADR^- T cells, and CD115⁺ cells.

CONCLUSION

These findings suggest that the tumor immune microenvironment is an important factor in identifying DCIS cases with the highest risk for recurrence and that manipulating the immune microenvironment may be an efficacious strategy to alter or prevent disease progression.

How to use magnetic resonance imaging following neoadjuvant chemotherapy in locally advanced breast cancer

Magnetic resonance imaging (MRI) is highly sensitive in identifying residual breast cancer following neoadjuvant chemotherapy (NAC), and consequently is a commonly used imaging modality in locally advanced breast cancer patients. In these patients, tumor response is an important prognostic indicator. However, discrepancies between MRI findings and surgical pathology are well documented. Overestimation of residual disease by MRI may result in greater surgery than is actually required while underestimation may result in insufficient surgery. Thus, it is important to understand when MRI findings are reliable and when they are less accurate. MRI most accurately predicts pathology in triple negative, Her2 positive and hormone receptor negative tumors, especially if they are of a solid imaging phenotype. In these cases, post-NAC MRI is highly reliable for surgical planning. Hormone receptor positive cancers and those demonstrating non mass enhancement show lower concordance with surgical pathology, making surgical guidance more nebulous in these cases. Radiologists and surgeons must assess MRI response to NAC in the context of tumor subtype. Indiscriminate interpretations will prevent MRI from achieving its maximum potential in the pre-operative setting.

Abstract PD1-5: Characterizing the Tumor Immune MicroEnvironment (TIME) in high-risk ductal carcinoma in situ

Background: Ductal carcinoma in situ (DCIS) of the breast is a premalignant condition. Although DCIS is treated as an obligate precursor of invasive ductal carcinoma, the rate and latency of progression from DCIS to invasive breast cancer (IBC) in the absence of treatment are unknown. DCIS is not one condition, but rather a spectrum of disease and although DCIS itself is not a lethal condition, women with DCIS are at higher risk of developing subsequent IBC over a time period of 1-20 years depending on DCIS subtype. Features of DCIS that are associated with high risk of recurrence include large size (&gt; 5cm), high grade, comedo necrosis, palpable mass, hormone receptor (HR) negativity, and HER2 positivity. The objective of this study was to characterize the tumor immune microenvironment (TIME) of these high-risk DCIS lesions.

Methods: Forty-eight cases of high grade DCIS, enriched for large, confluent lesions and history of recurrence were age matched with 64 cases of non-high grade DCIS. IHC analyses were performed as single or two-color stains for the following antigens: CD68, CD8, CD4, CD20, HLA-DR, CD115, FoxP3, PCNA, Mac387, MRC1, ALDH, CD24, CD44, Ki-67, and HER2. HR status was determined from ER and PR staining results in pathology reports. A Nuance multispectral imaging system was used to image and spectrally unmix each stain. Protocols for automated image analysis were developed using CellProfiler software. Associations between immune cell populations and clinical parameters (tumor palpability, recurrence, HR status, HER2 status, and Van Nuys score [12-point scale: margins, age, size, grade]) were identified with non-parametric Spearman correlation tests.

Results: We found a high macrophage infiltrate associated with a high Van Nuys score, palpability, and high Ki-67. High CD115 (CSF-1 receptor) was associated with HER2+, high Ki-67, and recurrence. Mac387+ cells and FoxP3+ regulatory T cells (Treg) were associated with high Van Nuys score, comedo necrosis, high Ki-67, HR- and HER2+. Interestingly, both Mac387 and CD115 were expressed on tumor cells as well as macrophages and high CD115 staining on tumor cells was associated with recurrence. The presence of CD8+HLA-DR-negative T cells throughout a section was associated with high Van Nuys score, HR-, HER2+, and recurrence. In contrast, CD8+ T cells within the nests of tumor cells were negatively associated with Van Nuys score, palpability, and comedo necrosis. A tumor immune microenvironment score (TIME score) was developed based on the proportions of various immune cell populations. A high TIME score was significantly associated with high Van Nuys scores as well as with recurrence.

Summary: These results demonstrate that high risk DCIS features (palpability, high Van Nuys score, high proliferation, HR-, HER2+, and increased recurrence) are associated with a suppressed tumor immune micro-environment (high FoxP3+ cells, CD68+Mac387+ cells, CD8+HLA-DR-neg T cells, and upregulated CD115). These high risk lesions truly represent an opportunity to prevent cancer. Identifying these high risk lesions with the help of tumor immune microenvironment markers and manipulating the DCIS TIME via local or systemic immunotherapeutic strategies may represent an ideal preventative intervention.

Citation Format: Michael J Campbell, Rita Mukhtar, Ekene Obi-Okoye, Booyeon Han, Vickram Tandon, Sarah Zheng, Zelos Zhu, Max Endicott, Max Wicha, Linda Lindstrom, Alfred Au, Frederick Baehner, Joe Gray, Laura Esserman. Characterizing the Tumor Immune MicroEnvironment (TIME) in high-risk ductal carcinoma in situ [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 PD1-5.

Abstract 165: Suppressed immunity and macrophages characterize high risk high grade DCIS

Background: High grade in situ (DCIS) features associated with high recurrence include large size (&gt;5cm), comedo necrosis, palpable mass, hormone receptor (HR) negativity, and HER2 positivity. Given that high grade, HR-neg invasive breast cancers have an inflammatory component (significant macrophage infiltration) we sought to characterize the immune microenvironment of DCIS to assess patterns of immune cell infiltrates associated with high risk lesions.

Methods: 48 cases of high grade DCIS were age matched with 64 cases of non-high grade DCIS. Immunohistochemical analyses were performed as single color stains for the following antigens: CD115, FoxP3, ALDH, Ki-67, HER2. Two color IHC was performed for the following antigen pairs: CD68/PCNA; CD68/Mac 387; CD8/HLA-DR; CD68/MRC1, and CD24/CD44. HR status was determined from ER and PR staining results in pathology reports. For each case, 3 hot spots were identified and marked on 10 consecutive sections. Nuance multispectral imaging software was used to image each hot spot. Protocols for automated image analysis were developed using CellProfiler software. Clinical parameters of interest included tumor palpability, recurrence, and Van Nuys score, (12 point scale-margins, age, size, grade). Associations were identified with non-parametric Spearman correlation test.

Results: High numbers of macrophages were associated with high Van Nuys score, palpability, and high Ki-67. High CD115 (CSF-1 receptor/c-fms) was associated with HER2+, high Ki-67, and recurrence. Mac387+ cells and FoxP3+ regulatory T cells (Treg) were significantly associated with high Van Nuys score, comedo necrosis, high Ki-67, HR- and HER2+. Interestingly, both Mac387 and CD115 were expressed on tumor cells as well as macrophages and high CD115 staining on tumor cells was associated with recurrence. The presence of CD8+HLA-DR negative T cells throughout a section was associated with high Van Nuys score, HR-, HER2+, and recurrence. In contrast, CD8+ T cells within the nests of tumor cells were negatively associated with Van Nuys score, palpability, and comedo necrosis.

Conclusions: Suppressed immunity (high Treg and CD8+HLA-DR neg T cells) and upregulated CD115 and Mac387 expression on both tumor cells and macrophages were strongly correlated with high risk DCIS features (increased recurrence, palpability, high Van Nuys scores, high proliferation, HR- and HER2+). These results suggest that manipulation of the immune microenvironment in DCIS, via local stimulation of the immune system, depletion of Treg, and/or manipulation of macrophages could potentially alter disease progression. Targeted agents are in trials and could be tested in preoperative window trials using these biomarkers to monitor the impact of presurgical immunotherapy.

Citation Format: Michael J. Campbell, Rita Mukhtar, Ekene Obi-Okoye, Booyeon Han, Vick Tandon, Sarah Zheng, Zelos Zhu, Max Endicott, Max Wicha, Linda Lindstrom, Alfred Au, Frederick Baehner, Joe Gray, Laura Esserman. Suppressed immunity and macrophages characterize high risk high grade DCIS. [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 165. doi:10.1158/1538-7445.AM2014-165

Abstract P3-14-12: Risk factors for local regional recurrence in patients undergoing breast conserving surgery following neoadjuvant chemotherapy and validation of the MD Anderson prognostic index

Background: Breast conserving surgery (BCS) is a primary goal of neoadjuvant chemotherapy (NAC) in patients with locally advanced breast cancer, especially with recent improvements in tumor response. Patient selection for BCS following NAC may be different than classic local regional recurrence (LRR) risk factors. Here we investigate risk factors for LRR and attempt to validate the MD Anderson Prognostic Index (MDAPI) for LRR in a single institution series.

Methods: Data were analyzed for 178 consecutive patients treated at one institution who underwent NAC followed by BCS and whole breast radiotherapy between the years 1999 and 2011. Using univariate and multivariate analysis, multiple clinicopathologic factors were investigated, as well as the subgroups of the MDAPI. Chi-square tests were used to compare the LRR-free survival rates between subgroups.

Results: The median follow-up was 70.33 months and the 5-year LRR-free survival was 93.18%. Multivariate analysis demonstrated that clinical stage and pathologic stage were both statistically significant for LRR-free survival, while pattern of residual disease was of borderline statistical significance. The MDAPI was not significantly associated with LRR-free survival (MDAPI low 93.80%, Intermediate 88.23%, High 88.89%).

Five-Year Local Regional Recurrence -Free Survival According to Clinicopathologic Factors # Patients5yr LRR-Free SurvivalPathologic Stage p = 0.03301580.0%14292.5%27692.5%3994.6%pCR38100%Clinical Stage p = 0.0291580.0%213796.3%33883.8%MDAPI Score P = 0.506Low (0 or 1)12993.80%Int (2)3488.23%High (3)988.89%*MDAPI Score Factors  cN Stage P = 0.305cN0-N116593.3%cN2-N31070%LVI P = 0.453No-LVI15793.5%Yes-LVI2390.9%pT&gt;2cm P = 0.158Residual Tumor Morphology P = 0.055Multifocal Resid Tumor5996.5%Solitary Mass6690.6%No Resid Tumor5394.3%*These factors make up the MDA Prognostic Index

Conclusion: Overall the 5-year LRR-free survival was high at 93.18%, which compares favorably to similar neoadjuvant patient cohorts who receive mastectomy instead of BCS. Our analysis indicates clinical stage and pathologic stage are significant in predicting LRR. Of the four predictive factors utilized by the MDAPI, only multifocal residual disease showed weak predictive power (p = 0.055) in our population; however, it correlated with higher LRR-free survival, the opposite of its indication in the MDAPI. The MDAPI was not useful in our patient population; the risk groups did not significantly correlate with LRR-free survival. This may be secondary to low total number of recurrence events and also the small number of patients in the MDAPI-high group (9 patients had an MDAPI score of 3, and none had a score of 4). As further data emerge regarding biology of tumors and recurrence, it may be a combination of molecular profiling and residual cancer burden that is a better predictor for LRR.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-14-12.

Biology of breast cancer in Nigerian women: a pilot study

BACKGROUND

Compared to the developed world, there are relatively few studies that describe the tumor biology of breast cancer in African women. While little is known about the tumor biology, clinical and epidemiologic studies suggest that breast cancer in African women are characterized by presentation at late stage and poor clinical outcomes. Analysis of the biological features of breast cancers in Nigerian women was designed to bring additional insight to better understand the spectrum of disease, the phenotypes that present, and the types of interventions that might improve outcomes.

MATERIALS AND METHODS

We performed histological analyses for hormone receptors (estrogen and progesterone receptors), HER2, and tumor infiltrating macrophages (TAM) on 17 breast cancers, obtained from Abia State University Teaching Hospital (Aba, Nigeria), between November 2008 and October 2009. On a subset of these cases, we investigated the potential role of a virus in the etiology of these aggressive cancers.

RESULTS

The majority of cases in this cohort were characterized as high grade (100% were grade III), triple-negative (65%), and occur in young women (mean age 47 years). We observed high infiltration of TAMs in these tumors, but no evidence of a viral etiology.

CONCLUSION

Our findings indicate that breast cancers in Nigerian women have a highly aggressive phenotype (high grade, hormone receptor negative), which is similar to other studies from Africa and other developing nations, as well as from African American women, but is significantly different from Caucasian women in the developed world. The presence of high numbers of TAMs in these tumors raises the possibility of targeting the immune microenvironment for therapeutic interventions.

P4-09-19: PCNA+ Tumor Associated Macrophages Are Associated with M1 and M2 Gene Expression, and Confer Poor Prognosis in the Absence of Anti-Tumor Immune Environment

Background

Tumor associated macrophages (TAMs) promote breast tumor progression through the production of angiogenic factors, stromal breakdown factors, and the suppression of adaptive immunity. TAMs are recruited from the circulation to the tumor site, and can undergo a spectrum of phenotypic changes, with two contrasting activation states described in the literature: the M1 anti-tumoral and M2 pro-tumoral phenotypes. We previously identified a population of PCNA+ TAMs associated with high grade, hormone receptor (HR) negative tumors with poor outcomes. We hypothesized that high PCNA+ TAMs would be associated with expression of M2 related genes.

Methods

We used immunohistochemistry to measure PCNA+ TAM levels (double positive for PCNA and CD68) in 135 invasive breast cancer cases from the I-SPY 1 Trial, a prospective neoadjuvant trial with serial core biopsies and gene array data. We developed gene-sets representing M1 related, M2 related, and anti-tumoral immune response (represented by cytotoxic T cells and MHC Class II) genes based on literature review. We compared PCNA+ TAM levels, expression of these gene-sets, and outcomes.

Results

Higher than mean PCNA+ TAM counts were associated with increasing grade (p &lt; 0.001), HR negativity (p &lt; 0.001), and decreased recurrence free survival (RFS, p = 0.05). Among subjects who had a pathologic complete response (pCR), there was no difference in RFS between those with high versus low PCNA+ TAMs. Among subjects without pCR, those with high PCNA+ TAMs had significantly worse RFS than those with low PCNA+ TAMs (p = 0.0028). In the 95 subjects with both PCNA+ TAM results and gene expression arrays available, high PCNA+ TAM levels were associated with more M1 than M2 related genes. The gene-set representing anti-tumoral immune environment was not by itself associated with RFS. However, those subjects with both high PCNA+ TAMs and the absence of anti-tumoral immune response gene expression had significantly worse RFS than those with high PCNA+ TAMs but the presence of anti-tumoral immune related genes (p = 0.01).

Quality-of-life issues in psoriasis

Although the lesions of psoriasis might be "skin deep," the disease has dramatic physical,mental, social and financial ramifications for those it afflicts. Clinicians should be able to assess the impact of psoriasis on quality of life (QOL) to measure disease severity,monitor improvement, and ensure equitable funding for research and reimbursement. The development of various clinical tools to assess health-related QOL has led to increasing awareness of the extent of patient morbidity. The fact that psoriasis causes disability comparable to that seen in other major systemic diseases has important implications for how it should be viewed and treated.

Population dynamics of some Pakistan mosquitoes: temporal changes in reproductive status, age structure and survivorship of Anopheles culicifacies, An. stephensi and Culex tritaeniorhynchus

The reproductive biology and age-structure of female Anopheles culicifacies, An. stephensi and Culex tritaeniorhynchus were studied at rural Punjabi villages near Lahore, Pakistan, during 1976-1980. Both Anopheles remained gonotrophically active throughout the year with blood-fed, gravid, parous and virgin females collected during all months. Culex tritaeniorhynchus populations bifurcated into reproductively active, non-overwintering and reproductively inactive, overwintering populations in October and/or November. Most female Cx. tritaeniorhynchus overwintered as inseminated nullipars with ovaries arrested at follicular State I; however, host-seeking and parous females were collected during every month of the year. Survivorship was calculated for each species by three methods and was negatively correlated with mean monthly ambient temperature. The ovarian tracheolation method provided inadequate estimates of parity for females collected at diurnal resting sites which refed the night of oviposition, but was suitable for Cx. tritaeniorhynchus females captured at bovid baits. The dilatation method of Polovodova was applied to all three species and yielded survivorship patterns which were constant with age and agreed well with a log-linear model. Anopheles culicifacies survived longer than did An. stephensi and thus was considered a better vector of malaria. Age-specific survivorship tables were constructed for all three species for those periods of the year when the gonotrophic rhythm was constant and generations were overlapping.