Impact of COVID-19 on patients with metastatic breast cancer: REthink Access to Care and Treatment survey results

Aim: Patients with metastatic breast cancer (MBC) may be vulnerable to changes in healthcare management, safety standards and protocols that occurred during the COVID-19 pandemic. Materials & methods: The REthink Access to Care & Treatment (REACT) survey assessed USA-based patient perspectives on COVID-19-related impacts to their MBC treatment experience between 27 April 2021 and 17 August 2021. Results: Participants (n = 341; 98.5% females, mean age 50.8 years) reported that overall oncology treatment quality was maintained during the pandemic. Delayed/canceled diagnostic imaging was reported by 44.9% of participants while telemedicine uptake was high among participants (80%). Conclusion: Overall, MBC care was minimally affected by the pandemic, possibly due to the expanded use of telemedicine, informing MBC management for future public health emergencies.

Incidence, risk factors, and management of alpelisib-associated hyperglycemia in metastatic breast cancer

PURPOSE

The combination of fulvestrant with alpelisib, a PI3K inhibitor, improves progression-free survival in metastatic hormone receptor-positive, PIK3CA-mutant breast cancer. This study describes the incidence, risk factors, and treatment of alpelisib-associated hyperglycemia.

METHODS

Patients with metastatic breast cancer who received alpelisib from 2013 to 2021 at Memorial Sloan Kettering Cancer Center were included in this retrospective study. Alpelisib prescription dates and patient/tumor characteristics were abstracted from medical records. Risk factors associated with hyperglycemia and alpelisib dose reduction/discontinuation were evaluated using Pearson's χ2 tests.

RESULTS

Among 247 patients, baseline median body mass index was 25.4 kg/m2 and median hemoglobin A1c (HbA1c) was 5.5%. A total of 152 patients (61.5%) developed any-grade hyperglycemia and 72 patients (29.2%) developed grade 3-4 hyperglycemia; median time to onset was 16 days. A total of 100 patients (40.5%) received alpelisib on a clinical trial; rates of hyperglycemia were significantly higher in patients treated as standard care versus on a clinical trial (any-grade hyperglycemia 80.3% vs. 34.0%, grade 3-4 hyperglycemia 40.2% vs. 13.0%, p < .001). Baseline HbA1c was significantly associated with development of hyperglycemia (p < .001) and alpelisib dose reduction/discontinuation (p = .015). Among those who developed hyperglycemia, 101 (40.9%) received treatment, most commonly with metformin. A total of 49 patients (19.8%) were referred to an endocrinologist, which was associated with SGLT2 inhibitor prescription (p = .007).

CONCLUSIONS

Rates of hyperglycemia among patients treated with alpelisib as standard care were significantly higher than patients treated on clinical trials. Elevated baseline HbA1c is associated with alpelisib-induced hyperglycemia and requiring dose modification. Optimization of glycemic status before alpelisib initiation should become routine practice.

Breast Cancer Macrophage Heterogeneity and Self-renewal are Determined by Spatial Localization

Tumor-infiltrating macrophages support critical steps in tumor progression, and their accumulation in the tumor microenvironment (TME) is associated with adverse outcomes and therapeutic resistance across human cancers. In the TME, macrophages adopt diverse phenotypic alterations, giving rise to heterogeneous immune activation states and induction of cell cycle. While the transcriptional profiles of these activation states are well-annotated across human cancers, the underlying signals that regulate macrophage heterogeneity and accumulation remain incompletely understood. Here, we leveraged a novel ex vivo organotypic TME (oTME) model of breast cancer, in vivo murine models, and human samples to map the determinants of functional heterogeneity of TME macrophages. We identified a subset of F4/80highSca-1+ self-renewing macrophages maintained by type-I interferon (IFN) signaling and requiring physical contact with cancer-associated fibroblasts. We discovered that the contact-dependent self-renewal of TME macrophages is mediated via Notch4, and its inhibition abrogated tumor growth of breast and ovarian carcinomas in vivo, as well as lung dissemination in a PDX model of triple-negative breast cancer (TNBC). Through spatial multi-omic profiling of protein markers and transcriptomes, we found that the localization of macrophages further dictates functionally distinct but reversible phenotypes, regardless of their ontogeny. Whereas immune-stimulatory macrophages (CD11C+CD86+) populated the tumor epithelial nests, the stroma-associated macrophages (SAMs) were proliferative, immunosuppressive (Sca-1+CD206+PD-L1+), resistant to CSF-1R depletion, and associated with worse patient outcomes. Notably, following cessation of CSF-1R depletion, macrophages rebounded primarily to the SAM phenotype, which was associated with accelerated growth of mammary tumors. Our work reveals the spatial determinants of macrophage heterogeneity in breast cancer and highlights the disruption of macrophage self-renewal as a potential new therapeutic strategy.

Pre-diagnosis lipid levels and mortality after obesity-related cancer diagnosis in the Women's Health Initiative cardiovascular disease biomarker cohort

BACKGROUND

Published studies have demonstrated inconclusive relationships between serum lipid levels and mortality after cancer.

METHODS

The primary objective was to evaluate the relationship between fasting lipid levels and mortality after cancer. Data were obtained on baseline lipids and outcomes after cancer from 1263 postmenopausal women diagnosed with 13 obesity-related cancers who were part of the Women's Health Initiative (WHI) lipid biomarkers cohort. Obesity-related cancers included incident invasive cancers of the breast, colorectum, endometrium, esophagus (adenocarcinoma), kidney, liver, gallbladder, pancreas, ovaries, small intestine, thyroid, stomach, as well as multiple myeloma. Baseline lipid measurements included high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, and non-HDL-cholesterol. Outcomes were all cause, cancer-specific, and CVD mortality. Multivariable Cox proportional hazards models were used to measure associations between lipid levels and mortality (all cause, cancer, and CVD) after a cancer diagnosis, with lipids analyzed as continuous variables.

RESULTS

Among women with obesity-related cancer, there were 707 deaths, of which 379 (54%) were due to cancer and 113 (16%) were due to CVD. Mean time from blood draw to cancer diagnosis was 5.1 years (range: 0.05-10 years). LDL-C values above the 95th percentile were associated with higher risk of all-cause mortality (p < 0.001), and cancer-specific mortality (p < 0.001), but not mortality due to CVD. Non-HDL-C values above the 65th percentile were associated with higher risk of all-cause mortality (p = 0.01) and mortality due to CVD (p = 0.003), but not cancer-specific mortality (p = 0.37). HDL-C values above the 95th percentile were associated with lower all-cause mortality (p = 0.002), and above the 65th percentile with lower cancer-specific mortality (p = 0.003), but no significant relationship with mortality due to CVD was observed.

CONCLUSIONS

The relationship between pre-diagnosis fasting lipid levels and mortality after cancer diagnosis is complex. These results suggest that improved lipid control through lifestyle and anti-lipid medications could have a meaningful impact on outcomes after cancer.

Submitochondrial Protein Translocation Upon Stress Inhibits Thermogenic Energy Expenditure

Mitochondria-rich brown adipocytes dissipate cellular fuel as heat by thermogenic energy expenditure (TEE). Prolonged nutrient excess or cold exposure impair TEE and contribute to the pathogenesis of obesity, but the mechanisms remain incompletely understood. Here we report that stress-induced proton leak into the matrix interface of mitochondrial innermembrane (IM) mobilizes a group of proteins from IM into matrix, which in turn alter mitochondrial bioenergetics. We further determine a smaller subset that correlates with obesity in human subcutaneous adipose tissue. We go on to show that the top factor on this short list, acyl-CoA thioesterase 9 (ACOT9), migrates from the IM into the matrix upon stress where it enzymatically deactivates and prevents the utilization of acetyl-CoA in TEE. The loss of ACOT9 protects mice against the complications of obesity by maintaining unobstructed TEE. Overall, our results introduce aberrant protein translocation as a strategy to identify pathogenic factors.

One-Sentence Summary

Thermogenic stress impairs mitochondrial energy utilization by forcing translocation of IM-bound proteins into the matrix.

Abstract P5-08-07: Dietary patterns among women with early-stage breast cancer from the Healthy Living Program

Background: Diet is a modifiable risk factor for breast cancer risk and mortality. Current guidelines recommend a diet that provides a diverse array of nutrients, comprised predominantly of fruits/vegetables and whole grains, with limited added sugar. The Healthy Living Program (HLP) is a clinical program at Memorial Sloan Kettering Cancer Center for patients with early-stage breast cancer that offers longitudinal, personalized lifestyle management starting at the time of diagnosis. Here, we report dietary patterns among the HLP cohort and association with baseline body mass index (BMI). Methods: We included all patients enrolled in the HLP from September 2020-February 2022. At the time of enrollment, participants complete a survey containing the National Cancer Institute (NCI) Dietary Screener Questionnaire (DSQ), which consists of consumption frequency questions for 26 food items over the past month. Total daily intake equivalents are calculated for foods from every diet factor group according to standard NCI DSQ scoring as follows: 1) Total daily cup equivalents of fruits/vegetables, which includes fruit, fruit juice, salad, potatoes, beans, other vegetables, tomato sauce, salsa, and pizza; 2) Total daily ounce equivalents of whole grains, which includes cereal, whole grain bread, whole grain rice, and popcorn; 3) Total teaspoon (tsp) equivalents of added sugars from candy, doughnuts, cookies/cake/pie, cereal, ice cream, and sugar-sweetened beverages including soda, fruit drinks, and sugar/honey in coffee/tea. Adherence to recommended daily intake of fruits/vegetables, whole grains, and added sugars was assessed as per the 2020-2025 Dietary Guidelines, the American Institute for Cancer Research, and the World Health Organization guidelines. Patient and tumor characteristics were abstracted from medical records. Results: Among the 399 patients included, the median age at diagnosis was 58 and median baseline BMI was 26.1 kg/m2. 45 patients had carcinoma in situ (11.3%), 296 had stage I disease (74.2%), 51 had stage II disease (12.8%), and 7 had stage III disease (1.8%). 316 had hormone-receptor positive disease (89.3%), 24 had HER2-positive disease (6.8%), and 26 had triple-negative disease (7.3%). 106 participants (27%) met the guideline recommendation of ≥4-5 cup equivalents of fruits/vegetables daily and 3 participants (0.8%) met the guideline recommendation of ≥3 ounces equivalents of whole grains daily. All patients in the cohort met the guideline recommendation of &lt; 6 tsp equivalents of added sugars daily. Only 2 patients (0.5%) met guidelines for all three diet factors. Baseline BMI was significantly higher among patients who did not meet the recommended fruit/vegetable intake than among those who did (26.9 kg/m2 vs. 24.5 kg/m2, p=0.016). There were no significant differences in BMI between those who did and did not adhere to the other diet factor guidelines and no significant association between tumor stage or histology and dietary guideline adherence. Conclusion: Most patients with early-stage breast cancer did not meet the recommended daily intake of fruits/vegetables or whole grains. Participants who did not meet the fruit and vegetable intake guideline had significantly higher BMI at diagnosis. These findings indicate that lifestyle assessment near the time of breast cancer diagnosis identifies patients that could benefit from personalized dietary interventions to optimize prognostic factors such as BMI.

Citation Format: Bethina Liu, Sherry Shen, Erica Salehi, Yuan Chen, Nicolas Toumbacaris, Johnny Allsop, Cara Anselmo, Stacie Corcoran, Bridget Kelly, Rocco Magnoli, Andrea Smith, Melissa Emerzian, Julia Brockway-Marchello, Doreen Bacotti, Mark E. Robson, Neil M. Iyengar. Dietary patterns among women with early-stage breast cancer from the Healthy Living Program [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 P5-08-07.

Translating energy balance research from the bench to the clinic to the community: Parallel animal-human studies in cancer

Advances in energy balance and cancer research to date have largely occurred in siloed work in rodents or patients. However, substantial benefit can be derived from parallel studies in which animal models inform the design of clinical and population studies or in which clinical observations become the basis for animal studies. The conference Translating Energy Balance from Bench to Communities: Application of Parallel Animal-Human Studies in Cancer, held in July 2021, convened investigators from basic, translational/clinical, and population science research to share knowledge, examples of successful parallel studies, and strong research to move the field of energy balance and cancer toward practice changes. This review summarizes key topics discussed to advance research on the role of energy balance, including physical activity, body composition, and dietary intake, on cancer development, cancer outcomes, and healthy survivorship.

Biomineralogical signatures of breast microcalcifications

Microcalcifications, primarily biogenic apatite, occur in cancerous and benign breast pathologies and are key mammographic indicators. Outside the clinic, numerous microcalcification compositional metrics (e.g., carbonate and metal content) are linked to malignancy, yet microcalcification formation is dependent on microenvironmental conditions, which are notoriously heterogeneous in breast cancer. We interrogate multiscale heterogeneity in 93 calcifications from 21 breast cancer patients using an omics-inspired approach: For each microcalcification, we define a "biomineralogical signature" combining metrics derived from Raman microscopy and energy-dispersive spectroscopy. We observe that (i) calcifications cluster into physiologically relevant groups reflecting tissue type and local malignancy; (ii) carbonate content exhibits substantial intratumor heterogeneity; (iii) trace metals including zinc, iron, and aluminum are enhanced in malignant-localized calcifications; and (iv) the lipid-to-protein ratio within calcifications is lower in patients with poor composite outcome, suggesting that there is potential clinical value in expanding research on calcification diagnostic metrics to include "mineral-entrapped" organic matrix.

Obesity promotes breast epithelium DNA damage in women carrying a germline mutation in BRCA1 or BRCA2

Obesity, defined as a body mass index (BMI) ≥ 30, is an established risk factor for breast cancer among women in the general population after menopause. Whether elevated BMI is a risk factor for women with a germline mutation in BRCA1 or BRCA2 is less clear because of inconsistent findings from epidemiological studies and a lack of mechanistic studies in this population. Here, we show that DNA damage in normal breast epithelia of women carrying a BRCA mutation is positively correlated with BMI and with biomarkers of metabolic dysfunction. In addition, RNA sequencing showed obesity-associated alterations to the breast adipose microenvironment of BRCA mutation carriers, including activation of estrogen biosynthesis, which affected neighboring breast epithelial cells. In breast tissue explants cultured from women carrying a BRCA mutation, we found that blockade of estrogen biosynthesis or estrogen receptor activity decreased DNA damage. Additional obesity-associated factors, including leptin and insulin, increased DNA damage in human BRCA heterozygous epithelial cells, and inhibiting the signaling of these factors with a leptin-neutralizing antibody or PI3K inhibitor, respectively, decreased DNA damage. Furthermore, we show that increased adiposity was associated with mammary gland DNA damage and increased penetrance of mammary tumors in Brca1+/- mice. Overall, our results provide mechanistic evidence in support of a link between elevated BMI and breast cancer development in BRCA mutation carriers. This suggests that maintaining a lower body weight or pharmacologically targeting estrogen or metabolic dysfunction may reduce the risk of breast cancer in this population.

Adjuvant enzalutamide for the treatment of early-stage androgen-receptor positive, triple-negative breast cancer: a feasibility study

PURPOSE

Chemotherapy with or without immunotherapy remains the mainstay of treatment for triple-negative breast cancer (TNBC). A subset of TNBCs express the androgen receptor (AR), representing a potential new therapeutic target. This study assessed the feasibility of adjuvant enzalutamide, an AR antagonist, in early-stage, AR-positive (AR +) TNBC.

METHODS

This study was a single-arm, open-label, multicenter trial in which patients with stage I-III, AR ≥ 1% TNBC who had completed standard-of-care therapy were treated with enzalutamide 160 mg/day orally for 1 year. The primary objective of this study was to evaluate the feasibility of 1 year of adjuvant enzalutamide, defined as the treatment discontinuation rate of enzalutamide due to toxicity, withdrawal of consent, or other events related to tolerability. Secondary endpoints included disease-free survival (DFS), overall survival (OS), safety, and genomic features of recurrent tumors.

RESULTS

Fifty patients were enrolled in this study. Thirty-five patients completed 1 year of therapy, thereby meeting the prespecified trial endpoint for feasibility. Thirty-two patients elected to continue with an optional second year of treatment. Grade ≥ 3 treatment-related adverse events were uncommon. The 1-year, 2-year, and 3-year DFS were 94%, 92% , and 80%, respectively. Median OS has not been reached.

CONCLUSION

This clinical trial demonstrates that adjuvant enzalutamide is a feasible and well-tolerated regimen in patients with an early-stage AR + TNBC. Randomized trials in the metastatic setting may inform patient selection through biomarker development; longer follow-up is needed to determine the effect of anti-androgens on DFS and OS in this patient population.

Impact of obesity and white adipose tissue inflammation on the omental microenvironment in endometrial cancer

BACKGROUND

A complex relationship between adipose tissue and malignancy, involving an inflammatory response, has been reported. The goal of this work was to assess the prevalence of white adipose tissue (WAT) inflammation in patients with endometrial cancer (EC), and the association with circulating inflammation markers. Furthermore, the aim was to characterize the pathways activated in and the cell type composition of adipose tissue in patients with EC.

METHODS

Adipose tissue and blood samples were prospectively collected from 101 patients with EC at initial surgery. WAT inflammation was determined based on adipocytes surrounded by macrophages forming crown-like structures. Circulating levels of metabolic syndrome-associated and inflammatory markers were quantified. RNA-sequencing was performed on adipose samples (n = 55); differential gene expression, pathway, and cellular decomposition analyses were performed using state-of-the-art bioinformatics methods.

RESULTS

WAT inflammation was identified in 46 (45.5%) of 101 EC patients. Dyslipidemia, hypertension, and diabetes mellitus were significantly associated with WAT inflammation (p < .05). WAT inflammation was associated with greater body mass index (p < .001) and higher circulating levels of leptin, high-sensitivity C-reactive protein, and interleukin-6, as well as lower levels of adiponectin and sex hormone-binding globulin (p < .05). Transcriptomic analysis demonstrated increased levels of proinflammatory and pro-neoplastic-related gene expression in inflamed omental adipose tissue.

CONCLUSIONS

WAT inflammation is associated with metabolic syndrome, obesity, and inflammatory markers, as well as increased expression of proinflammatory and proneoplastic genes.

Insulin-Lowering Diets in Metastatic Cancer

Hyperinsulinemia is an independent risk factor for cancer mortality. Insulin-lowering dietary strategies such as calorie restriction (CR), low-carbohydrate or ketogenic diets (KD), and intermittent fasting (IF) are aimed at reducing systemic stores of nutrients utilized by cancer cells, attenuating insulin-related growth signaling, and improving obesity-related metabolic parameters. In this narrative review, we searched the published literature for studies that tested various insulin-lowering diets in metastatic cancer in preclinical and clinical settings. A total of 23 studies were identified. Of these, 14 were preclinical studies of dietary strategies that demonstrated improvements in insulin levels, inhibition of metastasis, and/or reduction in metastatic disease burden in animal models. The remaining nine clinical studies tested carbohydrate restriction, KD, or IF strategies which appear to be safe and feasible in patients with metastatic cancer. These approaches have also been shown to improve serum insulin and other metabolic parameters. Though promising, the anti-cancer efficacy of these interventions, such as impact on tumor response, disease-specific-, and overall survival, have not yet been conclusively demonstrated. Studies that are adequately powered to evaluate whether insulin-lowering diets improve cancer outcomes are warranted.

Obesity and Breast Cancer Risk: The Oncogenic Implications of Metabolic Dysregulation

CONTEXT

Breast cancer is increasing in prevalence in parallel with rising rates of obesity worldwide. Obesity is recognized as a leading modifiable risk factor for the development of breast cancer; however, this association varies considerably by clinicopathologic features, and the underlying mechanisms are complex.

EVIDENCE ACQUISITION

Pubmed literature search using combinations of "obesity," "breast cancer risk," "diet," "exercise," "weight gain," "weight loss," "adipose tissue inflammation," "crown-like structure," "immune markers," "metformin," "gliflozins," "SGLT-2i," "GLP1-RA," and related terms.

EVIDENCE SYNTHESIS

Elevated body mass index and weight gain are associated with increased risk of postmenopausal, hormone receptor-positive breast cancer. Emerging evidence suggests that adverse measures of body composition in individuals of any weight can also confer increased breast cancer risk. Mechanistically, various factors including altered adipokine balance, dysfunctional adipose tissue, dysregulated insulin signaling, and chronic inflammation contribute to tumorigenesis. Weight loss and more specifically fat mass loss through lifestyle and pharmacologic interventions improve serum metabolic and inflammatory markers, sex hormone levels, and measures of breast density, suggesting a link to decreased breast cancer risk.

CONCLUSION

Incorporating markers of metabolic health and body composition measures with body mass index can capture breast cancer risk more comprehensively. Further studies of interventions targeting body fat levels are needed to curb the growing prevalence of obesity-related cancer.

Plant-Based and Ketogenic Diets As Diverging Paths to Address Cancer: A Review

Importance

As the incidence of cancer and metabolic disorders, such as obesity, concurrently rise, there has been increasing awareness of the pervasive effect of nutrition. The whole foods plant-based diet (WFPBD) and ketogenic diet (KD) have gained popularity in oncology, and this topic is increasingly permeating clinical dialogue.

Observations

Dietary intake is associated with multiple pathways involved in carcinogenesis and tumor progression. Consumption of a plant-enriched diet is associated with reduced cancer incidence and is recommended by dietary guidelines for cancer prevention. Despite a starkly different nutrient composition, a WFPBD and KD can be associated with weight loss, decreased inflammation, and decreased insulin levels. In addition, a WFPBD is associated with increased fiber, phytochemicals, and butyrate levels and decreased insulin-like growth factor 1 levels, whereas a KD exerts potential anticancer effects by increasing β hydroxybutyrate levels. A KD may be of interest in select, less common settings, such as tumors treated with phosphatidylinositol 3-kinase inhibitors, which induce hyperinsulinemia and hyperglycemia. Completed interventional trials have focused on increasing fruit and vegetable intake or reducing fat intake but have not specifically tested WFPBD or KD for cancer prevention or treatment. Currently available data support plant-based diets as opposed to KD as part of a lifestyle associated with reduced cancer risk. In the postdiagnosis setting, there are currently no rigorously tested approaches that support the recommendation of any diet to treat cancer.

Conclusions and Relevance

The results of this review suggest that the collective evidence supports plant-enriched diets vs KD for the reduction of cancer risk and the improvement of metabolic disorders in survivors. Additional prospective randomized clinical trials are needed to encourage use of dietary modification across the cancer continuum. Rigorous trial designs that adapt classical oncologic end points may identify populations that are likely to benefit from starkly contrasting diets. Current data support prioritization of plant-based diets, and future data could further personalize dietary recommendations in cancer populations.

Association between physical activity and neoadjuvant chemotherapy completion and pathologic complete response in primary breast cancer: the CANTO study

BACKGROUND

Regular physical activity is associated with improved symptom control in patients with breast cancer but its association with chemotherapy completion or response is unclear.

METHODS

Using a prospective design, 1075 breast cancer patients receiving neoadjuvant chemotherapy between March 2012 and February 2017 were studied. Physical activity was assessed using the Global Physical Activity Questionnaire [GPAQ-16], quantified in standardised MET-h/wk. Chemotherapy completion was defined as the proportion of patients completing planned treatment course, requiring dose reduction, or requiring dose delay. Response was evaluated by pathologic complete response (pCR). Associations between physical activity and primary outcomes were assessed using multivariable logistic regression models.

RESULTS

There was no differences between any chemotherapy completion outcome on the basis of physical activity classification. The percent of patients not completing planned treatment was 5.7% for ≦0.33 MET-h/wk, compared with 6.8% for 0.34-16.65 MET-h/wk, and 4.6% for ≥16.6 MET-h/wk (p = 0.52). No significant relationships were observed between physical activity dose classification and pCR for the overall cohort or upon stratification by clinical subtype.

CONCLUSION

Future studies are required to further investigate the relationship between pre-treatment levels of physical activity and function on treatment completion and response in breast and other cancer populations.

CLINICAL TRIAL REGISTRATION

NCT01993498.

Interim analysis of a single-center, single-arm, prospective phase 2 study to evaluate the efficacy and safety of benralizumab for alpelisib rash in metastatic PIK3CA-mutant, hormone receptor–positive breast cancer

12100

Background: Rash associated with increased peripheral eosinophils develops in approximately 50% of metastatic breast cancer patients receiving alpelisib. Antihistamines and corticosteroids have limited benefit. Refractory rash may lead to decreased dose intensity and affect clinical outcome. Benralizumab is an anti-IL-5Rα chimeric monoclonal antibody that depletes peripheral eosinophils and has demonstrated benefit in eosinophilic asthma and hypereosinophilic syndrome. We investigate the efficacy and safety of benralizumab for the treatment of alpelisib rash. Methods: We performed a single-center, single-arm, prospective phase 2 study to evaluate the efficacy and safety of benralizumab in cancer patients who developed CTCAE grade 2/3 skin events resulting from immunotherapy or targeted therapies with absolute blood eosinophil counts of ≥300/mcl. While remaining on culprit drugs, patients were treated with benralizumab 30mg once every 4 weeks for the first 3 doses followed by once every 8 weeks for 3 additional doses (approved dosing for eosinophilic asthma). Primary endpoint was clinical response measured as reduction in CTCAE grade 2/3 skin event to grade ≤1 by week 4. Secondary endpoints were patient quality of life (QoL) measured by skindex16, safety data, need for supportive oral corticosteroids, and changes in cytokines and eosinophil biomarkers. This interim analysis focuses on patients with PIK3CA-mutant metastatic breast cancer receiving alpelisib. Results: Between September 16th 2020 and January 1st 2022, we enrolled 10 metastatic breast cancer patients with grade 2/3 rash attributed to alpelisib (5 pts with G3). All patients had a reduction of rash to grade ≤1 (n = 10, p < 0.0001), and a decrease in peripheral absolute eosinophils (mean 500/mcl to 0, p < 0.0001). Of these, 6 patients had been on prophylactic oral antihistamines and 2 had oral steroid coadministration. QoL significantly improved (Skindex16 mean score 58 to 16, p = 0.0001) and eosinophils in skin histology decreased per HPF (mean 6.25 to 0.25, n = 8, p = 0.2) by week 4. An increase in IL-5 > 600% and reduction IL-6 and TNF-α > 50% were reported by week 4 and 8. Grade 1/2 mucositis in 4 patients were reported as adverse events. Conclusions: Our findings suggest that benralizumab is safe and effective for the treatment of grade 2/3 rash with eosinophilia related to alpelisib in patients with breast cancer. A reduction in rash severity was evidenced in all patients, along with improved QoL. Larger controlled studies are in development to evaluate the efficacy of benralizumab for the prevention of alpelisib rash. Clinical trial information: NCT04552288.

Refractive Shifts and Changes in Corneal Curvature Associated With Antibody-Drug Conjugates

PURPOSE

Antibody-drug conjugates (ADCs) are a class of cancer drug wherein some are associated with corneal abnormalities, but there is a dearth of published information on refractive shifts in patients receiving ADCs. Here, we evaluated the dynamics of refractive error and keratometry readings in patients with ADC-related keratopathy and microcyst-like epithelial changes (MECs).

METHODS

This study is a retrospective case series including 58 eyes of 29 patients with ADC-related keratopathy from a single tertiary care cancer referral center (MSKCC). One eye (29 total) was randomly assigned for statistical analysis. In addition, a subset analysis of MEC location-refractive error correlation was performed on 20 eyes. Clinical records including slitlamp examination, indirect ophthalmoscopy, calculated spherical equivalence (SE), keratometry, and visual acuity were recorded at baseline, during, and off treatment.

RESULTS

A subset analysis of MEC location-refractive error correlation of 20 eyes revealed the following: Peripheral MECs were significantly associated with hyperopic shifts (P value < 0.001) and paracentral/central associated with myopic shifts (P value < 0.001). In the full cohort and on drug, the greatest change in SE from baseline was myopic (68%, as high as -4.75 D) and hyperopic (32%, as much as +3.75 D). Eighty-nine percent had a change in vision from baseline while on drug, but at the 3-month follow-up off drug, SE and vision returned to baseline in 33% and 82% of eyes.

CONCLUSIONS

Peripheral MECs were significantly associated with hyperopic shifts, and paracentral/central MECs were associated with myopic shifts. While on drug, most eyes had a myopic refractive shift, which corresponded with corneal steepening.

Targeting insulin feedback to enhance alpelisib (TIFA): A phase II randomized trial in metastatic, PIK3CA-mutant, hormone receptor–positive breast cancer

TPS1113

Background: Breast cancer is the most common malignancy among women in the U.S. and is a leading cause of cancer-related death. Among women with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer, 45% harbor activating mutations in the PIK3CA gene , which induces hyperactivation of phosphatidylinositol 3-kinase (PI3K) and drives cell growth and survival. The SOLAR-1 trial found that the combination of alpelisib, a PI3K inhibitor, and fulvestrant, an endocrine therapy, significantly improved progression-free survival compared to fulvestrant alone, leading to Food and Drug Administration approval in PIK3CA-mutated metastatic breast cancer. While PI3K inhibition induces apoptosis of cancer cells, inhibition of this pathway in the liver and skeletal muscle impairs physiologic insulin signaling leading to hyperglycemia. This affects > 60% of patients, results in grade 3-4 hyperglycemia in 36% of patients, and is a major cause of interrupted/reduced dosing or discontinuation. In preclinical models, application of a very low carbohydrate (ketogenic) diet or a sodium-glucose cotransporter 2 inhibitor (SGLT2i), a commonly used diabetes medication, minimized hyperglycemia and improved the anti-tumor efficacy of PI3K inhibition. These interventions are safe and feasible in cancer patients but have not been studied for the prevention of PI3K inhibitor-associated hyperglycemia. Methods: We are conducting a multicenter phase II clinical trial (NCT05090358) in patients receiving standard-of-care alpelisib plus fulvestrant to test the efficacy of three interventions (n = 106): 1) ketogenic diet, 2) low-carbohydrate diet, or 3) canagliflozin (a SGLT2i) in preventing alpelisib-associated hyperglycemia. The goal of this study is to mitigate a major toxicity of PI3K inhibitors and maximize their clinical efficacy. Eligible patients must be postmenopausal and have histologically confirmed HR-positive, HER2-negative metastatic breast cancer, ≥1 activating PIK3CA mutations, measurable disease per RECIST v1.1 or at least one predominantly lytic bone lesion, recurrence or progression during or after endocrine-based therapy, ECOG performance status of 0-1, hemoglobin A1c < 8%, and fasting blood glucose < = 140mg/dL. Prior CDK4/6 inhibitor use is allowed. The primary endpoint is the grade 3-4 hyperglycemia-free rate at 12 weeks. Secondary endpoints include the 6- and 12-month overall response rate, 6- and 12-month progression-free survival, alpelisib adherence, changes in systemic hormones and metabolites related to glucose homeostasis, changes in body composition, and quality of life. The first patient was enrolled on October 15, 2021. Participating sites include Memorial Sloan Kettering Cancer Center, Weill Cornell Medical Center, and the Ohio State University Wexner Medical Center. Clinical trial information: NCT05090358.

Characterization of alpelisib-associated hyperglycemia in metastatic breast cancer

1016

Background: For women with metastatic hormone receptor (HR)-positive, human epidermal growth factor 2 (HER2)-negative breast cancer, the combination of alpelisib and fulvestrant improves progression-free survival in those with PIK3CA mutations. Hyperglycemia is a major toxicity of PI3K inhibitors including alpelisib, which limits the clinical efficacy of these drugs due to interrupted/reduced dosing and discontinuation. In the SOLAR-1 trial that led to the Food and Drug Administration (FDA) approval of alpelisib, over 60% of patients developed hyperglycemia of any grade, and over 36% developed grade 3-4 hyperglycemia. Here we describe the incidence and treatment of alpelisib-associated hyperglycemia in a single center cohort. Methods: Patients with metastatic breast cancer who received alpelisib on a clinical trial or as part of standard care from 2013-2021 at Memorial Sloan Kettering Cancer Center were included in this retrospective study. Patient and tumor characteristics and pre-treatment body mass index (BMI), hemoglobin A1c, and serum glucose levels were abstracted from medical records. Alpelisib dose interruptions, reductions, or discontinuation was recorded as well as endocrinology consultation and use of anti-hyperglycemic agents. Date of progression and/or death were recorded where applicable. Results: 247 patients were included in this study, among whom 245 (99.1%) were female and 198 (80.1%) were white. 100 (40.5%) were treated on a clinical trial. Median baseline BMI was 25.4 kg/m2. Among 164 patients with baseline hemoglobin A1c levels available, 93 (56.7%) patients had normal hemoglobin A1c, 54 (32.9%) had prediabetes, and 17 (10.4%) had diabetes. 152 patients (61.5%) developed hyperglycemia of any grade; 56 (22.7%) developed grade 3 and 16 (6.5%) developed grade 4 hyperglycemia. The median time to onset of hyperglycemia was 16 days. BMI ≥25 kg/m2 or hemoglobin A1c ≥5.7% were strongly predictive of development of any-grade hyperglycemia ( p= 0.036 and p< 0.001, respectively) and grade 3-4 hyperglycemia ( p< 0.001 for both). Among those who developed hyperglycemia, 101 (40.9%) received treatment; 69 patients (27.9%) required only 1 anti-hyperglycemic agent whereas 9 (3.6%) required ≥3 anti-hyperglycemic agents. 49 (19.8%) were referred for endocrinology consult. In 66 patients (26.7%), alpelisib was held until resolution of hyperglycemia; 42 patients (17%) required dose reductions, and 11 (4.5%) discontinued alpelisib due to hyperglycemia. There was no significant difference in progression-free survival by hyperglycemia status or severity of hyperglycemia. Conclusions: Overweight BMI and hemoglobin A1c in the prediabetes or diabetes range were strongly predictive of developing alpelisib-associated hyperglycemia. Management of these co-morbidities prior to alpelisib treatment should be strongly considered.

Abstract P2-08-05: Plasma lipidomics analysis to identify potential non-invasive biomarkers for breast white adipose inflammation and aromatase expression levels

Background: The presence of white adipose tissue inflammation (WATi) in the breast has been associated with increased breast cancer risk and a worse clinical course. Elevated body mass index (BMI) and the post-menopausal state are both associated with breast WATi. Breast WATi has also been associated with increased expression of aromatase, the rate-limiting enzyme for estrogen biosynthesis. Currently, WATi is diagnosed in surgical samples of breast tissue by the identification of crown-like structures (CLS), which are comprised of a dead or dying adipocyte enveloped by macrophages. In contrast to surgical specimens, core biopsies have been shown to be inadequate for assessing WATi. Hence, there is an unmet need for strategies to non-invasively diagnose WATi. Here we used a novel lipidomics platform to identify potential non-invasive blood signatures of breast WATi. Methods: We conducted a cross-sectional study which included 100 patients who underwent mastectomy for breast cancer treatment or risk reduction. WATi was detected by CD68 immunohistochemistry to identify CLS. Breast aromatase expression levels were measured by qPCR. Clinicopathologic data were abstracted from electronic medical records. Lipidomic data were measured from blood plasma in collaboration with Waters Technologies Corporation. Lipid levels in association with breast WATi (presence/absence) and levels of aromatase expression (high/low) in non-tumorous breast tissue were examined using Welch’s t-test. P-values were adjusted for multiple comparisons by controlling the false discovery rate (FDR) using the Benjamini-Hochberg method. A logistic regression model was used to develop predictive models that evaluated potential lipid biomarkers of the presence of breast WATi and high breast aromatase expression levels. Stepwise regression was used for variable selection. AUC of the ROC curves was used to evaluate the performance of the predictive models. Results: Among 140 lipids analyzed, 13 were identified to be associated with breast WATi (P&lt;0.05, |log2FC|&gt;0.3). Specifically, 8 lipids had lower levels, and 6 lipids had higher levels in patients with breast WATi compared to those without. Levels of 7 lipids were significantly higher in patients with an increased level of aromatase (P&lt;0.05, |log2FC|&gt;0.3). After variable selection, LPE(22:6) (P=0.018), LPE(20:3) ES-(P=0.006), along with menopausal status and BMI provided an 86.0% (95% CI, 77.6%-94.5%) accuracy in predicting higher breast aromatase levels. Combining the effect of two lipids improved the accuracy by 10.4%(P=0.030) compared to the model only using menopausal status and BMI. A model with 5 lipids and menopausal status provided an 88.8%(95% CI, 81.9%-95.8%) accuracy for predicting breast WATi. The model performance improved by 9.2% (P=0.026) compared to the model only using menopausal status and BMI. Conclusions: Our study identified several lipid species that showed significant changes in association with breast WATi and levels of aromatase expression. Further validation of these blood signatures could provide non-invasive assessment of WATi and aromatase levels. The availability of such a diagnostic algorithm could help, in turn, to both identify women at elevated risk for breast cancer and for monitoring the efficacy of interventions aimed at reducing inflammation and aromatase levels.

Citation Format: Xiao Cai, Siqi Wei, Zizhuo Xu, Xi K Zhou, Andrew Peck, Steven Lai, Giorgis Isaac, Hernando Olivos, Nayasha Munjoma, Suraj Dhungana, Rob Plumb, Andrew J Dannenberg, Neil M Iyengar. Plasma lipidomics analysis to identify potential non-invasive biomarkers for breast white adipose inflammation and aromatase expression levels [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 P2-08-05.

Abstract P2-06-03: Obesity is associated with DNA damage in the breast epithelium of BRCA1 and BRCA2 mutation carriers: A role for estrogens & strategies for prevention

Background: Elevated bodyweight is a risk factor for breast cancer development in women who carry a mutation in the DNA repair enzymes BRCA1 and BRCA2. However, the mechanistic basis for this association is unknown. Breast adipose tissue undergoes significant changes in the setting of weight gain and obesity, including elevation in aromatase expression which leads to the increased biosynthesis of estrogens. Given that estrogens and estrogen metabolites have known pro-proliferative and genotoxic effects, we hypothesized that in BRCA1/2 mutation carriers, obesity may be positively associated with breast epithelial cell DNA damage, thereby increasing the risk of tumorigenesis. Furthermore, we examined the impact of inhibiting estrogen signaling or production on breast epithelium DNA damage in BRCA1/2 mutation carriers. Methods: Tissue microarrays were generated from non-cancerous breast tissue derived from 72 women carrying a mutation in BRCA1 or BRCA2 with known body mass index (BMI, kg/m2). Breast epithelium DNA damage was quantified by immunofluorescence (IF) staining of the DNA damage marker γH2AX. RNA-Seq was performed on breast organoids to assess differences in gene expression in relation to BMI. Associations between DNA damage and biomarkers of estrogen biosynthesis and bioavailability, including aromatase expression in the breast and circulating steroid hormone binding globulin (SHBG), were also evaluated. To explore the effect of blocking estrogen signaling or production on DNA damage, non-tumorous breast tissue explants from BRCA1/2 mutation carriers were cultured with fulvestrant, an estrogen receptor degrader, or metformin, an anti-diabetic drug that also reduces aromatase expression in the breast. Breast epithelial cell DNA damage was measured in control vs treated explants by γH2AX IF staining after 24 hours of treatment. Results: BMI was positively correlated with DNA damage in the breast epithelium of BRCA1/2 mutation carriers. Upstream analysis of gene expression in organoids derived from women with a BMI ≥ 30 compared to &lt;25, revealed activation of estrogen signaling. Further supporting a contribution of locally-derived and circulating estrogens to obesity-related DNA damage, breast aromatase expression was found to be positively correlated with DNA damage while circulating SHBG levels showed a negative correlation. Targeting estrogen signaling with fulvestrant significantly reduced breast epithelium DNA damage in breast explants from women carrying a mutation in either BRCA1 or BRCA2. Interestingly, metformin, also caused a significant reduction in DNA damage in breast explants. Conclusion: These data provide mechanistic evidence for the link between obesity and breast cancer in BRCA1 and BRCA2 mutation carriers through identification of a positive association between BMI and breast epithelial cell DNA damage. Importantly, these studies demonstrate that fulvestrant and metformin, drugs already approved for clinical use, decrease breast epithelial cell DNA damage. Further studies are warranted to determine whether targeting estrogens or use of metformin may be effective risk reduction strategies in BRCA1/2 mutation carriers with excess bodyweight who are at high risk for breast cancer development and currently have limited options for prevention beyond surgical intervention. Support: NIH R01CA215797, NIH F31CA236306, Anne Moore Breast Cancer Research Fund

Citation Format: Priya Bhardwaj, Neil M. Iyengar, Sofya Oshchepkova, Phoebe Piloco, Rohan Bareja, Olivier Elemento, Dilip D. Giri, Michael Pollak, Monica Morrow, Jason A. Spector, Kristy A. Brown. Obesity is associated with DNA damage in the breast epithelium of BRCA1 and BRCA2 mutation carriers: A role for estrogens & strategies for prevention [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 P2-06-03.

Abstract ES7-1: Harnessing Lifestyle Interventions via Diet and Exercise for Cancer Risk Reduction

A growing body of evidence indicates the importance of maintaining optimal metabolic health to reduce the risk of developing cancer and to improve outcomes after cancer diagnosis. Classical and normal weight obesity are states of metabolic dysfunction, and highly prevalent risk factors for the development and growth of several cancers. Classical obesity (defined as a body mass index (BMI) ≥ 30) is a risk factor for at least 13 different types of cancer. Recent data indicate that up to one third of normal weight individuals have metabolic obesity and, subsequently, increased risk for several cancers including breast and colon. Methods to risk-stratify metabolic health and subsequent cancer risk beyond traditional anthropometric metrics such as BMI could improve the efficacy of lifestyle interventions aimed at reducing cancer risk and improving cancer outcomes. In this educational session, the molecular mechanisms linking classical and normal weight obesity to cancer growth will be presented. Obesity-related dysfunction can contribute to cancer pathogenesis and treatment resistance through various mechanisms, including those mediated by insulin, leptin, adiponectin, pro-inflammatory mediators, and hormone signaling pathways, particularly in women. Furthermore, adiposity-related changes can influence tumor vascularity and inflammation in the tumor microenvironment, which can support tumor development and growth. Building upon these mechanistic findings, several clinical trials testing “precision lifestyle” interventions targeted at specific biologic pathways are ongoing. Several randomized control trials testing diet, exercise, and weight loss interventions in cancer populations have demonstrated the feasibility of such interventions. Here, the next generation of lifestyle interventions, such as digital interventions, that target specific pathway dysregulation will be presented. Additionally, pharmacologic interventions that target host metabolism are under study as adjuncts to standard cancer therapy. As rates of classical and normal weight obesity continue to increase, the development of individualized and biologically rational lifestyle interventions could represent an impactful strategy to reduce the worldwide cancer burden.

Citation Format: NM Iyengar. Harnessing Lifestyle Interventions via Diet and Exercise for Cancer Risk Reduction [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 ES7-1.

Abstract P1-14-03: Adjuvant enzalutamide for the treatment of early-stage androgen-receptor positive, triple negative breast cancer: A feasibility study

Background: Chemotherapy remains the mainstay of treatment for early-stage triple negative breast cancer (TNBC), yet targetable drivers of interest are under investigation. A subset of TNBCs express the androgen receptor (AR) and exhibit androgen-dependent growth. The AR-antagonist enzalutamide (ENZA) has shown activity in patients with metastatic AR+ TNBC. In this study, the feasibility of adjuvant ENZA in early-stage, AR+ TNBC was assessed (NCT02750358). As reported previously, this study met its primary endpoint of feasibility (Traina et al., ASCO 2019). Here we report secondary survival endpoints. Methods: In this single-arm, open-label, multi-center trial, patients with stage I-III, AR≥1% TNBC (ER/PR &lt;1%, HER2 negative) who had completed standard of care therapy were treated with ENZA 160 mg/day orally for 1 year. Patients who completed 1 year had an option to remain on adjuvant ENZA for another year. Toxicity was graded using National Cancer Institute Common Toxicity Criteria (NCI CTCAE) v4. The primary endpoint of this study was to evaluate feasibility of adjuvant ENZA, defined as the discontinuation rate due to toxicity, withdrawal of consent, other events related to tolerability or patient preference. The study was designed to discriminate between feasibility rates of 50% and 70% and was considered feasible if ≥29 out of 46 patients received ENZA for one year without discontinuation. Secondary endpoints included DFS, OS, safety, patient reported outcomes and correlative science. Patients who had disease progression (PD) during year 1 of ENZA without treatment discontinuation due to the above reasons were not included in the primary feasibility analysis but were included in secondary endpoint analyses for survival. Results: 50 patients enrolled on study from 05/2016 - 06/2018. The median age was 58 years (range 34-81 years); 8% had a germline BRCA1/2 (n=3) or PALB2 (n=1) mutation. 38% had stage I disease at diagnosis, 48% stage II and 14% stage III. 74% had grade 3 tumors. 94% of all patients received prior systemic chemotherapy, 81% of whom received prior anthracycline-taxane. 38% (n=19) were treated with prior neoadjuvant chemotherapy and 32% of those patients (n=6) achieved a pCR. Of those who did not achieve a pCR, 69% received adjuvant capecitabine. 47 patients were evaluable for the study endpoint and 35 patients completed 1 year of ENZA thereby meeting the prespecified trial endpoint for feasibility. 32 patients elected to continue into a second year of treatment. After a median follow-up of 140 weeks (range 4 - 236 weeks), 8 patients had a DFS event: 7 TNBC recurrences and 1 new primary breast cancer. The 1-year DFS was 94% (95% CI: 87 - 100%), 2-year DFS was 92% (95% CI: 84 - 99.8%) and the 3-year DFS was 80% (95% CI: 67 - 94%). The median DFS and OS have not yet been reached. Two patients died of TNBC recurrence after 55 and 59 weeks. There were no new or unexpected toxicities observed at study completion. Conclusion: This single-arm trial previously met its primary endpoint of feasibility in patients with early-stage AR+ TNBC. In this relatively high-risk, albeit highly selected patient population, the 3-year DFS measured 80% (95% CI: 67 - 94%) with an adjuvant endocrine therapy approach. Efforts to determine the optimal biomarker for AR+ TNBC are ongoing, so that patients most likely to respond to AR-antagonists in both the early and metastatic setting may be identified. Biomarker data from this study including PD-L1 status and tumor sequencing will be reported at the time of presentation.Funding and drug support for this study was provided by Astellas Pharma Global Development Inc./Pfizer Inc.

Citation Format: Elaine M Walsh, Ayca Gucalp, Sujata Patil, Marcia Edelweiss, Dara S Ross, Pedram Razavi, Shanu Modi, Neil M Iyengar, Rachel Sanford, Tiffany Troso-Sandoval, Mila Gorsky, Jackie Bromberg, Pamela Drullinsky, Diana Lake, Serena Wong, Patricia DeFusco, Nicholas Lamparella, Ranja Gupta, Tasmila Tabassum, Leigh Ann Boyle, Artavazd Arumov, Tiffany A Traina. Adjuvant enzalutamide for the treatment of early-stage androgen-receptor positive, triple negative breast cancer: A feasibility study [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 P1-14-03.

Blood biomarkers reflect the effects of obesity and inflammation on the human breast transcriptome

Obesity is a risk factor for the development of post-menopausal breast cancer. Breast white adipose tissue (WAT) inflammation, which is commonly found in women with excess body fat, is also associated with increased breast cancer risk. Both local and systemic effects are probably important for explaining the link between excess body fat, adipose inflammation and breast cancer. The first goal of this cross-sectional study of 196 women was to carry out transcriptome profiling to define the molecular changes that occur in the breast related to excess body fat and WAT inflammation. A second objective was to determine if commonly measured blood biomarkers of risk and prognosis reflect molecular changes in the breast. Breast WAT inflammation was assessed by immunohistochemistry. Bulk RNA-sequencing was carried out to assess gene expression in non-tumorous breast. Obesity and WAT inflammation were associated with a large number of differentially expressed genes and changes in multiple pathways linked to the development and progression of breast cancer. Altered pathways included inflammatory response, complement, KRAS signaling, tumor necrosis factor α signaling via NFkB, interleukin (IL)6-JAK-STAT3 signaling, epithelial mesenchymal transition, angiogenesis, interferon γ response and transforming growth factor (TGF)-β signaling. Increased expression of several drug targets such as aromatase, TGF-β1, IDO-1 and PD-1 were observed. Levels of various blood biomarkers including high sensitivity C-reactive protein, IL6, leptin, adiponectin, triglycerides, high-density lipoprotein cholesterol and insulin were altered and correlated with molecular changes in the breast. Collectively, this study helps to explain both the link between obesity and breast cancer and the utility of blood biomarkers for determining risk and prognosis.

Targeting obesity-related dysfunction in hormonally driven cancers

Obesity is a risk factor for at least 13 different types of cancer, many of which are hormonally driven, and is associated with increased cancer incidence and morbidity. Adult obesity rates are steadily increasing and a subsequent increase in cancer burden is anticipated. Obesity-related dysfunction can contribute to cancer pathogenesis and treatment resistance through various mechanisms, including those mediated by insulin, leptin, adipokine, and aromatase signalling pathways, particularly in women. Furthermore, adiposity-related changes can influence tumour vascularity and inflammation in the tumour microenvironment, which can support tumour development and growth. Trials investigating non-pharmacological approaches to target the mechanisms driving obesity-mediated cancer pathogenesis are emerging and are necessary to better appreciate the interplay between malignancy, adiposity, diet and exercise. Diet, exercise and bariatric surgery are potential strategies to reverse the cancer-promoting effects of obesity; trials of these interventions should be conducted in a scientifically rigorous manner with dose escalation and appropriate selection of tumour phenotypes and have cancer-related clinical and mechanistic endpoints. We are only beginning to understand the mechanisms by which obesity effects cell signalling and systemic factors that contribute to oncogenesis. As the rates of obesity and cancer increase, we must promote the development of non-pharmacological lifestyle trials for the treatment and prevention of malignancy.

Phase Ib/II study of capecitabine 7/7 schedule with neratinib in patients with HER2-positive metastatic breast cancer (MBC)

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Background: Neratinib (N) is a potent irreversible inhibitor of HER1, HER2, and HER4. Capecitabine (X) at optimal dose of 7 days on and 7 days off schedule (7/7) is well-tolerated with low rates of ≥ grade (G3) diarrhea. Methods: We conducted phase Ib/II study of N with X (7/7) with loperamide and colestipol prophylaxis in patients (pts) with pretreated HER2+ MBC (NCT03377387). Eligible pts had normal left ventricular ejection fraction (≥ 50%), any and < 4 prior chemotherapy-based treatments in phase Ib and II, respectively. Primary endpoint of phase Ib is maximum tolerated dose (MTD) and phase II is response rate. Secondary endpoints are safety, tolerability, and progression-free survival. Exploratory endpoint is to quantify cell-free DNA (cfDNA), correlating with response. Phase Ib follows traditional 3+3 design with 4 dose levels. In phase II, if > 3/9 respond, study is expanded to 24. If > 10/24 respond, study is deemed successful. Results: As of 2-4-2021, 10 pts were enrolled in phase Ib. 4 pts were treated at dose level 1 (X at 1500 mg BID at 7/7 and N at 240 mg daily); 2/4 pts experienced with G3 diarrhea during cycle 1. Six pts were treated at dose level -1 (X at 1000 mg BID 7/7 and N at 240 mg daily); 1 (17%) developed G3 diarrhea. The MTD is X at 1000 mg BID 7/7 and N at 240 mg daily. Twenty-two of 24 pts have been enrolled in phase II. Of 22 pts, data show 6 with partial response, 8 with stable disease, 3 with progressive disease, and 5 have not been assessed radiographically. Overall, 6/22 (27.3%) and 1/22 (4.5%) had all G and G3 diarrhea, respectively. Other significant toxicities at MTD included G2 hand foot syndrome (n = 1, 4.5%), G1 fatigue (n = 1, 4.5%) and G1 nausea (n = 4, 18%). Conclusions: The MTD is X at 1000 mg BID at 7/7 and N at 240 mg daily. This combination is safe and well tolerated with G3 diarrhea rate of 4.5%, which is significantly lower than the X 14/7 schedule in NALA study. The phase II portion of the study is near completion and updated result will be presented. Analysis of cfDNA, to correlate with response for phase II portion, is ongoing. Clinical trial information: NCT03377387.

Genomic profiling identifies somatic mutations predicting thromboembolic risk in patients with solid tumors

Venous thromboembolism (VTE) associated with cancer (CAT) is a well-described complication of cancer and a leading cause of death in patients with cancer. The purpose of this study was to assess potential associations of molecular signatures with CAT, including tumor-specific mutations and the presence of clonal hematopoiesis. We analyzed deep-coverage targeted DNA-sequencing data of >14 000 solid tumor samples using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets platform to identify somatic alterations associated with VTE. End point was defined as the first instance of cancer-associated pulmonary embolism and/or proximal/distal lower extremity deep vein thrombosis. Cause-specific Cox proportional hazards regression was used, adjusting for pertinent clinical covariates. Of 11 695 evaluable individuals, 72% had metastatic disease at time of analysis. Tumor-specific mutations in KRAS (hazard ratio [HR], 1.34; 95% confidence interval (CI), 1.09-1.64; adjusted P = .08), STK11 (HR, 2.12; 95% CI, 1.55-2.89; adjusted P < .001), KEAP1 (HR, 1.84; 95% CI, 1.21-2.79; adjusted P = .07), CTNNB1 (HR, 1.73; 95% CI, 1.15-2.60; adjusted P = .09), CDKN2B (HR, 1.45; 95% CI, 1.13-1.85; adjusted P = .07), and MET (HR, 1.83; 95% CI, 1.15-2.92; adjusted P = .09) were associated with a significantly increased risk of CAT independent of tumor type. Mutations in SETD2 were associated with a decreased risk of CAT (HR, 0.35; 95% CI, 0.16-0.79; adjusted P = .09). The presence of clonal hematopoiesis was not associated with an increased VTE rate. This is the first large-scale analysis to elucidate tumor-specific genomic events associated with CAT. Somatic tumor mutations of STK11, KRAS, CTNNB1, KEAP1, CDKN2B, and MET were associated with an increased risk of VTE in patients with solid tumors. Further analysis is needed to validate these findings and identify additional molecular signatures unique to individual tumor types.

Effects of Adiposity and Exercise on Breast Tissue and Systemic Metabo-Inflammatory Factors in Women at High Risk or Diagnosed with Breast Cancer

Excess body fat and sedentary behavior are associated with increased breast cancer risk and mortality, including in normal weight women. To investigate underlying mechanisms, we examined whether adiposity and exercise impact the breast microenvironment (e.g., inflammation and aromatase expression) and circulating metabo-inflammatory factors. In a cross-sectional cohort study, breast white adipose tissue (WAT) and blood were collected from 100 women undergoing mastectomy for breast cancer risk reduction or treatment. Self-reported exercise behavior, body composition measured by dual-energy x-ray absorptiometry (DXA), and waist:hip ratio were obtained prior to surgery. Breast WAT inflammation (B-WATi) was assessed by IHC and aromatase expression was assessed by quantitative PCR. Metabolic and inflammatory blood biomarkers that are predictive of breast cancer risk and progression were measured. B-WATi was present in 56 of 100 patients and was associated with older age, elevated BMI, postmenopausal status, decreased exercise, hypertension and dyslipidemia (Ps < 0.001). Total body fat and trunk fat correlated with B-WATi and breast aromatase levels (Ps < 0.001). Circulating C-reactive protein, IL6, insulin, and leptin positively correlated with body fat and breast aromatase levels, while negative correlations were observed for adiponectin and sex hormone binding globulin (P < 0.001). Inverse relationships were observed with exercise (Ps < 0.05). In a subgroup of 39 women with normal BMI, body fat levels positively correlated with B-WATi and aromatase expression (Ps < 0.05). In conclusion, elevated body fat levels and decreased exercise are associated with protumorigenic micro- and host environments in normal, overweight, and obese individuals. These findings support the development of BMI-agnostic lifestyle interventions that target adiposity. PREVENTION RELEVANCE: We report that individuals with high body fat and low exercise levels have breast inflammation, higher breast aromatase expression, and levels of circulating metabo-inflammatory factors that have been associated with increased breast cancer risk. These findings support interventions to lower adiposity, even among normal weight individuals, to prevent tumor growth.

Effects of obesity on breast aromatase expression and systemic metabo-inflammation in women with BRCA1 or BRCA2 mutations

Obesity is associated with an increased risk of breast cancer in post-menopausal women and decreased risk in pre-menopausal women. Conversely, in BRCA1/2 mutation carriers, pre-menopausal obesity is associated with early-onset breast cancer. Here we show that obese, pre-menopausal BRCA1/2 mutation carriers have increased levels of aromatase and inflammation in the breast, as occurs in post-menopausal women. In a prospective cohort study of 141 women with germline BRCA1 (n = 74) or BRCA2 (n = 67) mutations, leptin, and aromatase expression were higher in the breast tissue of obese versus lean individuals (P < 0.05). Obesity was associated with breast white adipose tissue inflammation, which correlated with breast aromatase levels (P < 0.01). Circulating C-reactive protein, interleukin-6, and leptin positively correlated with body mass index and breast aromatase levels, whereas negative correlations were observed for adiponectin and sex hormone-binding globulin (P < 0.05). These findings could help explain the increased risk of early-onset breast cancer in obese BRCA1/2 mutation carriers.

Obesity and Energy Balance Considerations in Triple-Negative Breast Cancer

ABSTRACT

Obesity is an increasingly prevalent state of energy imbalance that contributes to breast cancer risk and outcomes. The effects of obesity differ by breast cancer subtype and menopause. While most studies have focused on postmenopausal hormone receptor-positive disease, less is known about the relationship between obesity and triple-negative breast cancer (TNBC). Here we will review the observations linking obesity to TNBC, the socioeconomic disparities that contribute to obesity-related TNBC, and putative biologic mechanisms. Finally, we will consider the impact of obesity on surgical and medical treatment of TNBC and novel strategies to improve energy balance after cancer diagnosis.

Association between regional body fat and cardiovascular disease risk among postmenopausal women with normal body mass index

AIMS

Central adiposity is associated with increased cardiovascular disease (CVD) risk, even among people with normal body mass index (BMI). We tested the hypothesis that regional body fat deposits (trunk or leg fat) are associated with altered risk of CVD among postmenopausal women with normal BMI.

METHODS AND RESULTS

We included 2683 postmenopausal women with normal BMI (18.5 to <25 kg/m2) who participated in the Women's Health Initiative and had no known CVD at baseline. Body composition was determined by dual energy X-ray absorptiometry. Incident CVD events including coronary heart disease and stroke were ascertained through February 2017. During a median 17.9 years of follow-up, 291 incident CVD cases occurred. After adjustment for demographic, lifestyle, and clinical risk factors, neither whole-body fat mass nor fat percentage was associated with CVD risk. Higher percent trunk fat was associated with increased risk of CVD [highest vs. lowest quartile hazard ratio (HR) = 1.91, 95% confidence interval (CI) 1.33-2.74; P-trend <0.001], whereas higher percent leg fat was associated with decreased risk of CVD (highest vs. lowest quartile HR = 0.62, 95% CI 0.43-0.89; P-trend = 0.008). The association for trunk fat was attenuated yet remained significant after further adjustment for waist circumference or waist-to-hip ratio. Higher percent trunk fat combined with lower percent leg fat was associated with particularly high risk of CVD (HR comparing extreme groups = 3.33, 95% CI 1.46-7.62).

CONCLUSION

Among postmenopausal women with normal BMI, both elevated trunk fat and reduced leg fat are associated with increased risk of CVD.

The optimal living and survivorship program: Piloting a novel survivorship care model

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Background: Multiple agencies define cancer survivorship as beginning at the time of diagnosis. However, traditional care models deliver “survivorship care” months or years after diagnosis, which can cause care disruption and “transition anxiety”. We hypothesized that an approach centered around wellbeing could be applied across the cancer continuum (starting at diagnosis) and serve as a novel survivorship care model. Methods: We developed the Optimal Living and Survivorship Program with 3 key components: 1) a centralized model that provides multidisciplinary care; 2) an individualized Wellness Plan (WP); and 3) enrollment at the time of diagnosis to mitigate post-treatment transition. Participants complete a digital wellness questionnaire (WQ) prior to the 1st medical oncology consult, receive a validated algorithm-based WP, and meet with a Wellness Advanced Practice Provider (WAPP). The WP consists of individualized education and referrals (e.g., nutrition, exercise, financial counseling). The WAPP will assume post-treatment (“survivorship”) care. We piloted this approach in patients diagnosed with breast cancer beginning in 11/19. The primary outcome is feasibility defined by completion of the WQ. Secondary outcomes include participation in the WAPP visits, attendance at appointments, and quality of life (QOL). Results: Due to COVID-19, the pilot was paused in 2/20. Data collected from 11/19 through 2/20 reveal a total of 67 eligible patients with newly diagnosed breast cancer were approached, with 65 enrolled. All participants completed the WQ and all received a WP with supportive referrals and educational resources. All participants engaged with WP recommendations. Participants were screened at high risk for an average of 3.8 unmet needs, and 98% were at high risk for 2 or more needs at time of diagnosis. Exercise was the highest unmet need (83%). There was 76% adherence with referral to the program’s Exercise Physiologist. Other areas of needs were nutrition (59%) and sleep quality (51%). WAPP tele-visits began in 6/20; visit completion rates will be presented. Qualitative data regarding patient experience and QOL will be obtained via interviews and feedback will be categorized in thematic domains. Conclusions: Most patients enrolled in the program, completed a WQ and engaged with the WP. Our findings suggest that this early intro to survivorship is feasible. Earlier engagement and incorporation of wellness and supportive services from time of diagnosis may improve our ability to address multifactorial needs during and after cancer therapy.

Lipid levels and survival after obesity-related cancer in the Women’s Health Initiative CVD biomarker cohort

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Background: Previous investigations have demonstrated an inconclusive relationship between lipid biomarkers and mortality after cancer. Methods: We used data from 2,279 postmenopausal women diagnosed with 13 obesity-related cancers, who were part of the Women’s Health Initiative (WHI) lipid biomarkers cohort, to evaluate the relationship between lipid levels measured at study entry prior to cancer diagnosis, and mortality after cancer. Baseline lipid measurements consisted of HDL-Cholesterol, LDL-Cholesterol, and non-HDL-Cholesterol with ranges of measurement listed in the table. Obesity-related cancers included: meningioma, thyroid, adenocarcinoma of esophagus, breast, multiple myeloma, liver, kidney, gallbladder, stomach, uterus, pancreas, ovaries, and colorectal. The age adjusted relationship between baseline lipids and all-cause mortality as well as mortality due to cancer were estimated using Cox proportional hazards models and Fine-Gray models, respectively. Results: The majority of women in the cohort had either desirable or acceptable lipid levels (86% HDL-C, 30% LDL-C and 61% non-HDL-C. Low vs. desirable HDL-C levels were associated with higher risk of all-cause mortality (hazard ratio (HR) 1.54, 95% confidence interval [CI] [1.48, 1.60], p <.001) and higher cancer mortality (sub-distribution hazard ratio (SHR)1.9, 95% CI [1.51, 2.3], p <.001). High non-HDL-C vs desirable, was associated with higher all-cause mortality (HR 1.13, 95% CI [1.06, 1.21], p = .001) however no significant impact on cancer mortality (SHR 1.06, 95% CI [0.87, 1.30], p = 0.563). LDL-C levels demonstrated a more complex relationship with mortality, nevertheless, very high LDL-C levels were associated with higher risk of all-cause mortality (HR 1.63, 95% CI,1.21-2.2, p = ,0.001) and cancer-specific mortality (HR 1.78, 95% CI 1.22-2.63, p = 0.003). Conclusions: Elevated LDL-C and lower HDL-C may be associated with a lower risk of all-cause and cancer specific mortality in women diagnosed with obesity related cancers in the WHI. Results of multivariable adjustment for important predictors of mortality including race/ethnicity, medication use and other socio-demographic and clinical factors will be presented. [Table: see text]

The optimal living and wellness program: Piloting a novel survivorship care model

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Background: Multiple national agencies define cancer survivorship as beginning at the time of cancer diagnosis. However, traditional care models deliver “survivorship care” months or years after diagnosis, which can lead to disruption in care and “transition anxiety”. We hypothesized that an approach centered around wellbeing could be applied across the cancer continuum (starting at diagnosis) and serve as a novel survivorship care model. Methods: We developed the Optimal Living and Wellness Program, a multilevel intervention with 3 key components: 1) a centralized model that provides coordinated multidisciplinary care; 2) an individualized Wellness Plan (WP); and 3) enrollment at the time of cancer diagnosis in order to mitigate the experience of post-treatment transition. Participants complete a digital wellness questionnaire (WQ) prior to the first medical oncology consult, receive a validated algorithm-based WP reviewed by a Wellness Coordinator, and meet with a Wellness Advanced Practice Provider (WAPP) via tele-medicine. The WP consists of individualized education and referrals to indicated supportive services (e.g., nutrition, exercise physiology, financial counseling, integrative medicine). The WAPP will ultimately assume care of the patient in the post-treatment (“survivorship”) phase. We piloted this approach in patients diagnosed with breast cancer beginning in November 2019. The primary outcome is feasibility defined by completion of the WQ. Secondary outcomes include participation in the WAPP visits, attendance at referral appointments, and quality of life (QOL). Results: As of January 31, 2020, a total of 39 eligible patients with newly diagnosed breast cancer were approached. Of these, 36 (92%) have completed the WQ. All 36 participants received a WP with indicated supportive referrals and educational resources. Initial WAPP tele-visits will begin in May 2020. Qualitative data regarding patient experience and QOL will be obtained via focused interviews and feedback will be categorized in thematic domains. Conclusions: In this pilot, the majority of patients with newly diagnosed breast cancer completed a WQ in advance of their initial medical oncology visit, indicating preliminary feasibility. Patient enrollment is ongoing, and updated data including additional feasibility metrics and QOL will be presented. Earlier patient engagement and incorporation of wellness and supportive services from time of diagnosis may significantly improve the transition to post-treatment care.

Developing a breast cancer tissue biobank in low and middle income countries (LMICs): A research program-based approach for improving molecular profiling

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Background: Breast cancer incidence and mortality is increasing in LMICs especially in sub-Saharan Africa, attributed to changes in lifestyle and possible biological differences. To study putative relationships among lifestyle factors, tumor biology, and the microenvironment, we aimed to develop a breast cancer tissue biobank linked with clinicopathologic and patient reported data in this resource constrained setting. Methods: We prospectively enrolled patients undergoing mastectomy at Obafemi Awolowo University Teaching hospital in Ile-Ife, Nigeria. Pre-operatively, a locally validated survey tool assessed lifestyle factors (diet and exercise); BMI and body composition (by bioimpedence) were measured. Fresh breast tissue was frozen or preserved in 10% neutral buffered formalin, or RNA later for future metabolomic work. Immunohistochemistry (IHC) for ER/PR and HER2 status was performed and read in Nigeria by a locally-trained pathologist, and Memorial Sloan Kettering. The primary outcome was feasibility assessed by successful collection of tissue, clinicopathologic data, and survey completion. Secondary outcomes were completion rate of tumor receptor IHC compared to historic rates and concordance of local vs MSK IHC. Results: From April 2018 to June 2019, 50 patients were enrolled (49 treatment and 1 risk reduction mastectomy). Clinicopathologic, body composition, and survey data, along with breast tissue were collected from all 50 patients. Patient characteristics in table below. Receptor IHC was complete in all patients (100%) compared to a historic rate of 29% (83/286) between 2010-17. Concordance of IHC between sites was 86%, 81% and 84% for subtypes (ER/PR/HER2). Conclusions: Establishing a tissue biobank with clinicopathologic and lifestyle data using locally-adapted protocols is feasible in Nigeria. Patient enrolment is ongoing and updated data will be presented. This initiative also increased local capacity for breast tumor phenotyping, which has critical implications for improving patient care. [Table: see text]

Development of Exercise as Interception Therapy for Cancer: A Review

IMPORTANCE

Observational data linking physical activity and exercise exposure with reduced risk of either development or progression of cancer have fueled interest in the initiation of large-scale definitive trials to test the association of exercise therapy with disease outcomes. However, several major knowledge gaps impede the rational and optimal design of such trials.

OBSERVATIONS

Critical requirements underpinning the success of several recent contemporary anticancer agents have included adequate demonstration of antitumor activity (in phase 1/2 trials) as well as identification of essential prerequisites (eg, biologically effective dose and predictors of response) permitting optimal design of definitive trials. The existing evidence base investigating exercise as a candidate anticancer preventive or treatment strategy is predominantly confined to observational data, which have several inherent limitations. Consequently, the antitumor activity of exercise remains unclear and, perhaps more important, such data are not sufficient to accurately derive the exercise dose, prescription regimen, or patients most likely to benefit from exercise. In adherence with translational frameworks for lifestyle therapy development, the need for early phase 1/2-equivalent trials to fill current knowledge gaps to optimize the development and potential efficacy of exercise therapy is highlighted.

CONCLUSIONS AND RELEVANCE

Exercise therapy has significant promise to be an efficacious and cost-effective therapy to improve cancer outcomes, with few toxic effects. Although most nontraditional therapies in cancer prevention and prognosis fail in definitive trials, these failures provide critical lessons for the continued development of exercise as a candidate anticancer therapy.

Efficacy and Safety of Gemcitabine With Trastuzumab and Pertuzumab After Prior Pertuzumab-Based Therapy Among Patients With Human Epidermal Growth Factor Receptor 2-Positive Metastatic Breast Cancer: A Phase 2 Clinical Trial

IMPORTANCE

Taxanes with trastuzumab and pertuzumab for initial treatment of human epidermal growth factor receptor 2 (ERBB2, formerly HER2)-positive metastatic breast cancer is associated with improved progression-free survival (PFS) and overall survival. While continued use of trastuzumab in therapeutic combinations after disease progression is standard, the efficacy of continuing pertuzumab is unknown.

OBJECTIVE

To evaluate the efficacy and safety of pertuzumab in combination with gemcitabine and trastuzumab after prior treatment with pertuzumab for ERBB2-positive metastatic breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

This is a phase 2 single-arm clinical trial of dual anti-ERBB2 therapy after prior treatment with pertuzumab. The study took place at a single academic center from March 2015 to April 2017 among women with ERBB2-positive metastatic breast cancer, prior pertuzumab-based treatment, and 3 or fewer prior chemotherapy regimens. Data were analyzed between January 2019 and March 2019.

INTERVENTION

Treatment consisted of gemcitabine, 1200 mg/m2 (later amended to 1000 mg/m2) on days 1 and 8 every 3 weeks, plus trastuzumab (8-mg/kg loading dose, then 6 mg/kg) and pertuzumab (840-mg loading dose, then 420 mg) once every 3 weeks.

MAIN OUTCOMES AND MEASURES

The primary end point was 3-month PFS. Based on prior trials, a target rate of 70% or higher was selected as the promising progression-free rate at 3 months. Secondary outcomes included safety, tolerability, and overall survival.

RESULTS

A total of 45 patients (median [range] age, 57.1 [31.7-77.2] years) were enrolled; 22 (49%) were treated in the second-line setting, and 23 (51%) were treated in the third-line setting or beyond. Of these, 22 (49%) received prior trastuzumab emtansine (T-DM1). At a median (range) follow-up of 27.6 (8.3-36.0) months, 3-month PFS was 73.3% (95% CI, 61.5%-87.5%). Overall, median PFS was 5.5 months (95% CI, 5.4-8.2 months). Treatment was well tolerated, with no occurrences of febrile neutropenia or symptomatic left ventricular systolic dysfunction.

CONCLUSIONS AND RELEVANCE

In this phase 2 trial, treatment with gemcitabine, trastuzumab, and pertuzumab after prior pertuzumab-based therapy for ERBB2-positive metastatic breast cancer was associated with a 3-month PFS rate of 73.3% and was well tolerated. Continuation of pertuzumab beyond progression was associated with apparent clinical benefit.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02252887.

Obesity-Associated Extracellular Matrix Remodeling Promotes a Macrophage Phenotype Similar to Tumor-Associated Macrophages

Obesity is associated with adipose inflammation, defined by macrophages encircling dead adipocytes, as well as extracellular matrix (ECM) remodeling and increased risk of breast cancer. Whether ECM affects macrophage phenotype in obesity is uncertain. A better understanding of this relationship could be strategically important to reduce cancer risk or improve outcomes in the obese. Using clinical samples, computational approaches, and in vitro decellularized ECM models, this study quantified the relative abundance of pro-inflammatory (M1) and anti-inflammatory (M2) macrophages in human breast adipose tissue, determined molecular similarities between obesity and tumor-associated macrophages, and assessed the regulatory effect of obese versus lean ECM on macrophage phenotype. Our results suggest that breast adipose tissue contains more M2- than M1-biased macrophages across all body mass index categories. Obesity further increased M2-biased macrophages but did not affect M1-biased macrophage density. Gene Set Enrichment Analysis suggested that breast tissue macrophages from obese versus lean women are more similar to tumor-associated macrophages. These changes positively correlated with adipose tissue interstitial fibrosis, and in vitro experiments indicated that obese ECM directly stimulates M2-biased macrophage functions. However, mammographic density cannot be used as a clinical indicator of these changes. Collectively, these data suggest that obesity-associated interstitial fibrosis promotes a macrophage phenotype similar to tumor-associated macrophages, which may contribute to the link between obesity and breast cancer.

Improving risk assessment of obesity-associated breast cancer

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Background: Elevated body mass index (BMI) is associated with increased risk of estrogen receptor (ER)-positive postmenopausal breast cancer. The risk is also elevated in women with a normal BMI but excess body fat. These risks may be driven by breast white adipose tissue inflammation (WATi), which is associated with elevated aromatase levels and systemic metabolic dysfunction (e.g. hyperinsulinemia). We hypothesized that body fat assessment is superior to BMI for detecting the pathophysiology that promotes obesity-related breast cancer, particularly among normal BMI women. Methods: Non-tumorous breast tissue was collected from women undergoing mastectomy for breast cancer treatment or prevention. Breast WATi was detected by the presence of crown-like structures in the breast, which are composed of a dead/dying adipocyte surrounded by CD68+ macrophages. Body composition was measured prior to mastectomy via dual energy X-ray absorptiometry. Exercise behavior was also assessed prior to surgery using the Godin Leisure Time Exercise Questionnaire. Associations among categorical variables were examined using Χ2 or Fisher’s exact test. Relationships between continuous variables were examined using the Spearman correlation. Results: From April 5, 2016 to August 31, 2018, 100 patients were enrolled; median age 49 (range 29 to 82) years. Breast WATi was present in 56/100 (56%) women and was associated with elevated BMI and body fat levels, breast adipocyte hypertrophy, postmenopausal status, metabolic syndrome and decreased physical activity (P < 0.05). Among 39 women with normal BMI, breast WATi was present in 14 (36%) and was associated with elevated body fat levels, breast adipocyte hypertrophy, dyslipidemia, and decreased physical activity (P < 0.05). There was no statistically significant association between BMI and breast WATi in the normal BMI group. Menopausal status and total fat mass had greater sensitivity and specificity for the detection of breast WATi compared to a BMI-based model (AUC 0.843 vs. 0.779, respectively). Conclusions: Measurement of body fat is superior to BMI for predicting breast inflammation, which has been shown to promote obesity-related breast cancer.

The prognostic significance of white adipose tissue inflammation in advanced-stage, high-grade, and serous endometrial cancers

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Background: Obesity is associated with worse outcomes in endometrial cancer, but the underlying mechanisms are poorly understood. In other obesity-related cancers, white adipose tissue inflammation (WATi) is an independent predictor of shortened cancer-specific survival. We hypothesized that WATi occurs in patients with endometrial cancers and is a prognostic marker of shortened survival. Methods: We conducted a retrospective cohort study in which patients with stage III or IV grade 3 endometrioid (G3) or serous endometrial cancer were included. Eligible subjects had archived omental and/or peri-nodal adipose tissue available. WATi was detected by the presence of dead/dying adipocytes surrounded by CD68+ macrophages forming a crown-like structure (CLS). Clinicopathologic data were abstracted from medical records. For association with WATi, Wilcoxon rank sum test was used for continuous variables, Fisher’s exact test for categorical variables. Log rank test was used to assess the association of WATi and survival. Results: A total of 95 patients who underwent debulking surgery from 2001–2017 were included (median age, 67 years; range, 33-86 years). Of these, 51 (54%) had WATi. The presence of WATi was unaffected by race, tumor histology or stage. Patients with WATi had a higher median body mass index (BMI) than those without WATi (32.17 and 27.33 kg/m2, respectively; P < 0.001) and were more likely to be obese (P = 0.01). Patients with the most severe WATi (n = 20) had shorter progression-free survival (PFS) and a trend suggesting shorter overall survival (OS) than those patients with less severe or no WATi (n = 75) (median PFS 15.8 vs 59.2 months, respectively, P = 0.001; median OS 33.9 vs 59.4 months, respectively, P = 0.059). Conclusions: Visceral adipose inflammation is prevalent in obese patients with advanced G3 and serous endometrial cancer. Severe inflammation was associated with significantly worse PFS.

Abstract P6-15-03: MBC Connect™, an open-access, patient-reported registry of de-identified data from patients living with metastatic breast cancer

Metastatic breast cancer (MBC) remains an incurable disease and is the cause of nearly all deaths from breast cancer. Several barriers prevent efficient research into various questions about living with MBC. A key unmet need is a national database for MBC patient-reported outcomes, which does not exist anywhere in the world. Furthermore, compartmentalized data prevents broad collaborative efforts. Treatment patterns and responses, survival times, and metastatic patterns are not documented systematically and remain unavailable. Large-scale data extraction is challenging, and expensive, and electronic medical records do not provide information regarding patient experiences. Methods: MBC Connect™ was created to help overcome these barriers. MBC Connect, which is sponsored by the Metastatic Breast Cancer Alliance, is a multi-national registry of participant reported information about their experience of MBC. MBC Connect allows MBC patients to voluntarily provide information about their disease, treatment outcomes, and experience of living with their disease so that researchers can gain insight into unmet needs in MBC. MBC Connect has three main goals: 1. Establish an interactive registry of patient-entered, de-identified data for MBC. 2. Create an open-access portal for researchers to study these data. 3. Create a connection between investigators of clinical trials and clinical research studies and registered users who may be interested in clinical trials. Results: MBC Connect collects, via the use of a mobile app (on a smartphone or tablet, iOS and Android compatible) or via a website for desktop users, participant consent, general patient characteristics and demographics, disease characteristics, genetics and tumor mutations, treatment history, quality of life data, and clinical trial experience. This information can be provided by patients living with MBC or their caregiver. The data are collected from responses to surveys and via creation of a treatment profile. The data are de-identified and made available on an open-access Researcher portal, allowing them to be used to advance multiple areas of research into MBC, including both medical treatment aspects and quality of life issues. An interactive feature of MBC Connect is that researchers may submit a request for participants to answer additional surveys. Participants may also be notified about clinical trials for which they may be eligible. In addition, participants will regularly receive “Insights,” which are engaging bytes of information related to MBC. Insights can offer general information about the disease, upcoming events, and other facts, or they can be personalized for the participant based on the information he or she has entered the registry. Conclusions: MBC Connect is a novel platform that aims to accelerate MBC research by providing open access to patient-reported, de-identified data about patients living with MBC. The overarching objective of this technologic initiative is to increase patient engagement with the research community.

Citation Format: Campbell L, De La Torre K, Williams CE, Mertz SA, Pollastro T, Hutton A, Newby J, Ellis MJ, Iyengar NM, Hurlbert MS. MBC Connect™, an open-access, patient-reported registry of de-identified data from patients living with metastatic breast cancer [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 P6-15-03.

Abstract P5-07-05: Obesity, adipose inflammation, and race in patients with early stage breast cancer

Background: Elevated body mass index (BMI) is associated with increased risk of estrogen receptor-positive postmenopausal breast cancer. Mechanistically, most individuals with elevated BMI have breast white adipose tissue inflammation (WATi) which confers increased breast cancer risk, particularly in those with existing benign breast disease. Individuals with WATi have elevated in-breast expression of aromatase and several systemic changes that increase breast cancer risk, including hyperinsulinemia and higher levels of C-reactive protein. However, women with normal BMI but high levels of body fat are also likely to harbor WATi and are at increased risk of postmenopausal breast cancer. The accuracy of BMI for assessing adiposity and predicting obesity-related disorders, including cancer, varies across race and ethnicity. Whether the association between BMI and WATi varies by race is unknown. Here we aimed to characterize relationships among breast WATi and clinicopathologic features in a racially diverse cohort undergoing mastectomy for breast cancer treatment.

Methods: Non-tumorous breast tissue and fasting blood were collected from women undergoing mastectomy for breast cancer treatment or prevention at a single center serving a racially diverse patient population. Breast WATi was detected by the presence of crown-like structures in the breast (CLS-B), which are composed of a dead/dying adipocyte surrounded by CD68+ macrophages. Clinicopathologic data were abstracted from electronic medical records. Associations among categorical variables were examined using Fisher's exact test. Relationships between continuous variables were examined using the Spearman correlation.

Results: As of May 18, 2018 62 patients have been accrued; median age 55 (range 32 to 84). Self-reported race distribution was: 36 (58%) Asian, 5 African American (8%), 20 (32%) Caucasian, and 1 (2%) unknown. Breast tissue has been analyzed for WATi in 60 cases thus far. Clinicopathologic features stratified by the presence or absence of breast WATi are presented in. Breast WAT inflammation was associated with obesity (P=0.02) and a trend to association was observed with dyslipidemia (P&lt;0.09).

VariableBreast WATi Absent (n=25)Breast WATi Present (n=35)Age, years  Median (range)51 (32 to 71)59 (36 to 80)BMI, kg/m2  Median (range)22.5 (18.1 to 35.3)28.0 (19.2 to 38.9)BMI Category  Underweight1 (4%)0 (0%)Normal16 (64%)10 (29%)Overweight5 (20%)18 (51%)Obese3 (12%)7 (20%)Race, n (%)  Asian15 (60%)19 (54%)African American2 (8%)3 (9%)Caucasian8 (32%)12 (34%)Unknown0 (0%)1 (3%)Menopausal Status, n (%)  Pre10 (40%)12 (34%)Post15 (60%)23 (66%)Hypertension, n (%)7 (28%)16 (46%)Diabetes mellitus, n (%)0 (0%)5 (14%)Dyslipidemia, n (%)1 (4%)11 (31%)

Conclusions: Breast adipose inflammation is associated with elevated BMI and possibly metabolic syndrome disorders in a racially diverse population. These findings are consistent with observations from predominantly Caucasian cohorts. Race-specific characteristics will also be examined. Study accrual is ongoing and updated results will be presented.

Citation Format: Iyengar NM, Siegel B, Malik M, Giri DD, Tsai J, Hughes M, Adam A, Williams S, Zhou XK, Rodgers W, Ginter P, Patel A, Yong F, Cherian A, August P, Dannenberg AJ. Obesity, adipose inflammation, and race in patients with early stage breast cancer [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 P5-07-05.

Abstract P1-15-03: Association between exercise, pathological complete response, and treatment tolerability in patients receiving neoadjuvant chemotherapy for operable breast cancer: Results from the CANTO study

Background: Randomized trials, although not all, suggest exercise therapy improves treatment completion rates / relative dose intensity in patients with early-stage breast cancer receiving adjuvant chemotherapy (CT). In addition, preclinical studies show that exercise therapy adds to the antitumor activity of standard CT in murine models of breast cancer. We evaluated the association between exercise and pathologic complete response (pCR) rate (i.e., ypT0ypN0) in patients receiving neoadjuvant CT for operable breast cancer.

Methods: Using a prospective design, patients with stage I-III breast cancer receiving anthracycline-taxane (± trastuzumab) neoadjuvant CT participating in a multicenter, national cohort study in France (CANTO, NCT01993498) completed questionnaire assessing self-reported exercise behavior (GPAQ 16). Multivariate logistic models were performed to determine the relationship between pre-CT exercise exposure (total MET-h/wk categorized into the proportion of patients meeting WHO exercise guidelines, the equivalent of ≥10 MET-h/wk), pCR rates, CT± trastuzumab dose reductions, delays, treatment completion or interruptions for the overall cohort and on the basis of clinical subtype.

Results: Between March, 2012 to December, 2014, a total of 989 patients participating in CANTO received neoadjuvant CT and completed GPAQ 16. Here we present interim analyses on 608 patients. Fifty-four percent of patients engaged on of ≥10 MET-h/wk prior to CT administration. In multivariable analysis for the overall cohort, exercise exposure was not associated with higher pCR (p=0.69). The pCR rate was 27.7% for patients reporting &lt;10 MET h/wkcompared with 28.0% for those reporting ≥ 10 MET-h/wk (OR, 1.02; 95% CI, 0.71-1.45). Stratification analyses indicated no differences on the basis of clinical subtype for hormone receptor (HR) positive/HER2 negative (&lt;10 MET h/wk: 15.1% vs. ≥ 10 MET h/wk: 16.5%; OR, 0.95, 0.41-2.16); HER2 positive (&lt;10 MET h/wk: 38.1% vs. ≥ 10 MET h/wk: 32.5%; OR, 0.62, 0.28-1.35); or triple-negative disease (&lt;10 MET h/wk: 33.3% vs. ≥ 10 MET h/wk: 36.7%; OR, 1.04, 0.52-2.10). Rates of CT dose reductions (&lt;10 MET h/wk: 16.1% vs. ≥ 10 MET h/wk: 18.3%), CT dose delays (&lt;10 MET h/wk: 19.9% vs. ≥ 10 MET h/wk: 19.8%), CT completion (&lt;10 MET h/wk: 12.03% vs. ≥ 10 MET h/wk: 11.45%) trastuzumab interruptions (&lt;10 MET h/wk: 9.01% vs. ≥ 10 MET h/wk: 7.95%) were also not different on the basis of exercise exposure.

Conclusion: On the basis of interim analyses, higher pretreatment exercise exposure is not associated with higher clinical response or treatment tolerability in breast cancer patients receiving uniform conventional neoadjuvant CT. Full results will be presented at the meeting.

Citation Format: Baker JL, Di Meglio A, El Mouhebb M, Iyengar NM, Michiels S, Cottu P, Lerebours F, Coutant C, Lesur A, Tredan O, Soulie P, Vanlemmens L, Jouannaud C, Levy C, Everhard S, Martin A-L, Arveux P, Fabrice A, Vaz Luis I, Jones LW. Association between exercise, pathological complete response, and treatment tolerability in patients receiving neoadjuvant chemotherapy for operable breast cancer: Results from the CANTO study [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 P1-15-03.

Association of Body Fat and Risk of Breast Cancer in Postmenopausal Women With Normal Body Mass Index: A Secondary Analysis of a Randomized Clinical Trial and Observational Study

Importance

Obesity is associated with an increased risk of breast cancer, including the estrogen receptor (ER)-positive subtype in postmenopausal women. Whether excess adiposity is associated with increased risk in women with a normal body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) is unknown.

Objective

To investigate the association between body fat and breast cancer risk in women with normal BMI.

Design, Setting, and Participants

This ad hoc secondary analysis of the Women's Health Initiative (WHI) clinical trial and observational study cohorts was restricted to postmenopausal participants with a BMI ranging from 18.5 to 24.9. Women aged 50 to 79 years were enrolled from October 1, 1993, through December 31, 1998. Of these, 3460 participants underwent body fat measurement with dual-energy x-ray absorptiometry (DXA) at 3 US designated centers with follow-up. At a median follow-up of 16 years (range, 9-20 years), 182 incident breast cancers had been ascertained, and 146 were ER positive. Follow-up was complete on September 30, 2016, and data from October 1, 1993, through September 30, 2016, was analyzed August 2, 2017, through August 21, 2018.

Main Outcomes and Measures

Body fat levels were measured at baseline and years 1, 3, 6, and 9 using DXA. Information on demographic data, medical history, and lifestyle factors was collected at baseline. Invasive breast cancers were confirmed via central review of medical records by physician adjudicators. Blood analyte levels were measured in subsets of participants.

Results

Among the 3460 women included in the analysis (mean [SD] age, 63.6 [7.6] years), multivariable-adjusted hazard ratios for the risk of invasive breast cancer were 1.89 (95% CI, 1.21-2.95) for the highest quartile of whole-body fat and 1.88 (95% CI, 1.18-2.98) for the highest quartile of trunk fat mass. The corresponding adjusted hazard ratios for ER-positive breast cancer were 2.21 (95% CI, 1.23-3.67) and 1.98 (95% CI, 1.18-3.31), respectively. Similar positive associations were observed for serial DXA measurements in time-dependent covariate analyses. Circulating levels of insulin, C-reactive protein, interleukin 6, leptin, and triglycerides were higher, whereas levels of high-density lipoprotein cholesterol and sex hormone-binding globulin were lower in those in the uppermost vs lowest quartiles of trunk fat mass.

Conclusions and Relevance

In postmenopausal women with normal BMI, relatively high body fat levels were associated with an elevated risk of invasive breast cancer and altered levels of circulating metabolic and inflammatory factors. Normal BMI categorization may be an inadequate proxy for the risk of breast cancer in postmenopausal women.

Trial Registration

ClinicalTrials.gov identifier: NCT00000611.

Prostaglandin E2 down-regulates sirtuin 1 (SIRT1), leading to elevated levels of aromatase, providing insights into the obesity-breast cancer connection

Obesity increases the risk of hormone receptor-positive breast cancer in postmenopausal women. Levels of aromatase, the rate-limiting enzyme in estrogen biosynthesis, are increased in the breast tissue of obese women. Both prostaglandin E₂ (PGE₂) and hypoxia-inducible factor 1α (HIF-1α) contribute to the induction of aromatase in adipose stromal cells (ASCs). Sirtuin 1 (SIRT1) binds, deacetylates, and thereby inactivates HIF-1α. Here, we sought to determine whether SIRT1 also plays a role in regulating aromatase expression. We demonstrate that reduced SIRT1 levels are associated with elevated levels of acetyl-HIF-1α, HIF-1α, and aromatase in breast tissue of obese compared with lean women. To determine whether these changes were functionally linked, ASCs were utilized. In ASCs, treatment with PGE₂, which is increased in obese individuals, down-regulated SIRT1 levels, leading to elevated acetyl-HIF-1α and HIF-1α levels and enhanced aromatase gene transcription. Chemical SIRT1 activators (SIRT1720 and resveratrol) suppressed the PGE₂-mediated induction of acetyl-HIF-1α, HIF-1α, and aromatase. Silencing of p300/CBP-associated factor (PCAF), which acetylates HIF-1α, blocked PGE₂-mediated increases in acetyl-HIF-1α, HIF-1α, and aromatase. SIRT1 overexpression or PCAF silencing inhibited the interaction between HIF-1α and p300, a coactivator of aromatase expression, and suppressed p300 binding to the aromatase promoter. PGE₂ acted via prostaglandin E2 receptor 2 (EP₂) and EP₄ to induce activating transcription factor 3 (ATF3), a repressive transcription factor, which bound to a CREB site within the SIRT1 promoter and reduced SIRT1 levels. These findings suggest that reduced SIRT1-mediated deacetylation of HIF-1α contributes to the elevated levels of aromatase in breast tissues of obese women.

Obesity-associated Breast Inflammation among Hispanic/Latina Breast Cancer Patients

Breast white adipose tissue inflammation (BWATi) is associated with obesity and higher breast cancer risk among non-Hispanic white women. Obesity is prevalent in Hispanic/Latina patients with breast cancer, and the occurrence of BWATi in this population is not well-characterized. The association between BWATi and body mass index (BMI) was evaluated in Hispanic/Latina patients with breast cancer who underwent mastectomy. BWATi was defined as the presence of crown-like structures of the breast (CLS-B), detected by CD68 IHC in nontumor breast tissue. BWATi severity was quantified as number of CLS-B/cm² Adipocyte diameter was measured using hematoxylin and eosin-stained breast tissue sections. Preoperative BMI (within 1 week prior to mastectomy) was categorized as normal (18.5-<25.0 kg/m²), overweight (25.0-<30.0 kg/m²), class I obesity (30.0-<35.0 kg/m²), and class II-III obesity (35.0 kg/m² or above). Patient charts were abstracted to record clinicopathologic features and liver function tests <90 days before mastectomy. The study included 91 women (mean age 69 years; range 36-96 years). Prevalence of BWATi increased with BMI (24% in normal weight, 34% in overweight, 57% in class I obesity, and 65% in class II-III obesity; P _trend <0.01). Severe BWATi (>0.27 CLS-B/cm²) was associated with higher BMI (P _trend = 0.046) and greater adipocyte diameter (P = 0.04). Adjusting for BMI, neoadjuvant chemotherapy, and elevated alanine aminotransferase were associated with severe BWATi, and current smoking was associated with mild BWATi (all P < 0.05). BWATi was associated with higher BMI in Hispanic/Latina patients with breast cancer, consistent with previously described associations in other populations.

FGFR1 underlies obesity-associated progression of estrogen receptor-positive breast cancer after estrogen deprivation

Obesity increases breast cancer mortality by promoting resistance to therapy. Here, we identified regulatory pathways in estrogen receptor-positive (ER-positive) tumors that were shared between patients with obesity and those with resistance to neoadjuvant aromatase inhibition. Among these was fibroblast growth factor receptor 1 (FGFR1), a known mediator of endocrine therapy resistance. In a preclinical model with patient-derived ER-positive tumors, diet-induced obesity promoted a similar gene expression signature and sustained the growth of FGFR1-overexpressing tumors after estrogen deprivation. Tumor FGFR1 phosphorylation was elevated with obesity and predicted a shorter disease-free and disease-specific survival for patients treated with tamoxifen. In both human and mouse mammary adipose tissue, FGF1 ligand expression was associated with metabolic dysfunction, weight gain, and adipocyte hypertrophy, implicating the impaired response to a positive energy balance in growth factor production within the tumor niche. In conjunction with these studies, we describe a potentially novel graft-competent model that can be used with patient-derived tissue to elucidate factors specific to extrinsic (host) and intrinsic (tumor) tissue that are critical for obesity-associated tumor promotion. Taken together, we demonstrate that obesity and excess energy establish a tumor environment with features of endocrine therapy resistance and identify a role for ligand-dependent FGFR1 signaling in obesity-associated breast cancer progression.