Aromatase Inhibitor Treatment Research Articles

Impact of a Physical Exercise and Health Education Program on Metabolic Syndrome and Quality of Life in Postmenopausal Breast Cancer Women Undergoing Adjuvant Treatment with Aromatase Inhibitors

Background and Objectives: Adjuvant treatment with aromatase inhibitors (AIs) in breast cancer (BC) survivors can cause adverse effects such as metabolic syndrome (MS) (insulin resistance, central obesity, atherogenic dyslipidemia, and hypertension) associated with morbidity and premature mortality. We evaluate the effect of a multimodal program based on physical exercise and health education on MS and health-related quality of life (QoL) in postmenopausal women with BC under AIs. Methods: A total of 56 postmenopausal women, diagnosed with BC, aged 60 years or older (mean age 67.2 years) and on hormonal treatment with AIs, were included in the multimodal physical exercise and health education program, and evaluated before and after their participation. The assessment of the five criteria of the MS included the following: waist circumference, high blood pressure, fasting glucose, triglycerides, and high-density lipoprotein cholesterol. Two main instruments were used to evaluate the impact of the intervention on QoL: the EORTC QLQ C30 (questionnaire for cancers in general) and the EORTC QLQ BR23 (specifically for breast cancer patients). The EuroQol 5D (EQ-5D) was also used to compare these results. Results: The percentage of women meeting the MS criteria was 37.7% at baseline and fell to 15.1% at 3 months after the intervention (p = 0.02). The intervention significantly reduced hypertension (p < 0.001), central obesity (p < 0.001), and the concentration of triglycerides (p = 0.016). No significant changes were observed in fasting glucose and HDL concentration. A statistically significant improvement was found in QoL (on both the QLQ30 and BR23 scales). A multivariate regression model analysis identified marital status (being married) (95% CI: 1.728–131.615, p = 0.014), and percentage of attendance at health education sessions (95% CI: 1.010–1.211, p = 0.029) as positive predictive variables of improvement in MS. Conclusions: The implementation of multimodal, community-based programs of physical exercise and health education improve the prevalence of MS and specific criteria of MS and QoL in postmenopausal women with breast cancer receiving AI treatment.

Aromatase inhibitors, bone microstructure, and estimated bone strength in postmenopausal women with breast cancer: a 5-year prospective study.

Aromatase inhibitors (AIs) are the standard treatment for early breast cancer (EBC) and are typical causative agents of cancer treatment-induced bone loss. However, the effects of long-term treatment with these drugs on bone microstructure remain unclear. This prospective, single-arm observational study included postmenopausal, non-osteoporotic women with hormone receptor-positive EBC. Patients who underwent dual-energy X-ray absorptiometry (DXA), high-resolution peripheral quantitative computed tomography (HR-pQCT), and tartrate-resistant acid phosphatase-5b (TRACP-5b) or procollagen type I N-terminal propeptide levels were compared at baseline and at 60months after commencing AI treatment. Fifteen women were included in the study, with a median age of 58years and a quartile range of 56.5-62.5years. At 60months, HR-pQCT revealed that the cortical area and thickness decreased with increased cortical porosity in the cortical bone. In addition, the number of trabeculae decreased and trabecular separation increased trabecular bones decreases, and trabecular bone separation opens, resulting in a decrease in the trabecular bone volume fraction. Total bone mineral density (BMD), trabecular volumetric BMD, and cortical volumetric BMD, and estimated bone strength significantly decreased. DXA BMD values significantly decreased in the total hip and femoral neck but not the lumbar spine. TRACP-5b values after 5years of AI treatment showed a significant negative correlation with the rate of change in the total volumetric BMD in the distal tibia. Postmenopausal women who received AIs for 5years for EBC experienced significant deterioration in the bone microstructure, BMD, and estimated bone strength.

Ischaemic cardiotoxicity of aromatase inhibitors in postmenopausal patients with early breast cancer in Denmark: a cohort study of real-world data

For aromatase inhibitor treatment (AIT) in breast cancer, there is an unresolved concern about ischaemic cardiotoxicity. We investigated the association between AIT and ischaemic cardiotoxicity in a prospective cohort of female patients with early breast cancer who received contemporary treatment in Denmark. In this prospective cohort study in Denmark, we identified postmenopausal patients of any age diagnosed with breast cancer as recorded in the nationwide Danish Breast Cancer Cooperative Group (DBCG) clinical database between Jan 1, 2009, and Dec 31, 2020, and linked them to other nationwide registries. Exclusion criteria included having a history of other primary cancer, less than 2 years of residency in Denmark, and no inclusion in a treatment protocol according to the DBCG database, including for metastatic or locally advanced breast cancer. Information on demography, hospital diagnoses, filled prescriptions, laboratory testing, and socioeconomic status were recorded. We stratified the patient cohort according to history (yes vs no) of selected cardiovascular disease defined as ischaemic heart disease, ischaemic stroke, and heart failure, and defined the primary outcome as two-point major adverse cardiovascular events (MACE; acute myocardial infarction or ischaemic stroke). We estimated cause-specific hazard ratios (HRs) according to allocation to AIT versus not in an intention-to-treat analysis using a Cox proportional hazards regression model with age as the underlying time scale, adjusting for demographic characteristics, tumour characteristics, and other anti-cancer treatments. 43 440 postmenopausal patients diagnosed with breast cancer were identified, of whom 32 635 were followed up and included in analyses. Of 29 118 postmenopausal patients with no history of selected cardiovascular disease, we observed 510 two-point MACEs among 22 135 patients allocated to AIT (incidence rate 4·3/1000 person-years of follow-up) and 170 two-point MACEs among 6983 patients not allocated to AIT (4·1/1000 person-years). The adjusted HR was 0·91 (95% CI 0·73-1·14) for patients allocated to AIT versus patients not allocated to AIT. Among 3517 patients with a history of selected cardiovascular disease, we observed 158 two-point MACEs among 2661 patients allocated to AIT (incidence rate 12·4/1000 person-years) and 50 two-point MACEs (12·1/1000 person-years) among 856 patients not allocated to AIT (adjusted HR 0·81 [95% CI 0·58-1·15]). Our findings do not support a clinically relevant ischaemic cardiotoxic potential of AIT in patients with early breast cancer and do not support avoiding AIT prescription in patients with early breast cancer. Bispebjerg and Frederiksberg Hospital, Kræftens Bekæmpelse, Fonden til Lægevidenskabens Fremme, Aase og Ejnar Danielsens Fond, Helsefonden, and Læge Sofus Carl Emil Friis og Hustru Olga Doris Friis' Legat.

8595 Brain Penetration Impedes SERD Efficacy in Breast Cancer Pre-clinical Models

Abstract Disclosure: S.E. Wardell: None. B. Chakraborty: None. S. Artham: None. M.A. Newlin: None. M. Kirkland: None. C. Chang: None. D.P. McDonnell: None. Most breast cancers express the estrogen receptor (ER, ESR1), and agents that target ER remain the cornerstone of interventions used to treat this disease at all stages. Aromatase inhibitors (AI), which block estrogen synthesis, and the selective ER downregulator (SERD) fulvestrant were developed with the goal of achieving absolute inhibition of ER signaling in tumors. However, it has been assumed that the clinical efficacy (and utility) of fulvestrant is somewhat limited by its poor pharmaceutical properties and the requirement that it be administered by intramuscular injection. This, together with the observation that the activating ESR1 mutations selected for during AI treatment are not effectively inhibited by fulvestrant, encouraged the development of new classes of SERDs that achieve sufficient exposure to saturate and degrade ER in tumors. The recent approval of the second-generation SERD elacestrant for the treatment of breast cancers harboring ESR1 mutations was a major advance in approaches to target ER in advanced breast cancer. Several additional oral SERDs have been developed and evaluated as potential treatments for advanced metastatic breast cancer. Despite showing substantial efficacy in pre-clinical assays that assess ER downregulation and gene transcription, and notably equivalent antitumor activities in cell line derived and PDX tumors in immunocompromised mice, the clinical development of the majority of these SERDs has been discontinued for lack of efficacy. In reviewing the available clinical data across many SERD programs, we noted that some drugs demonstrated a paradoxical, non-linear response curve with higher doses exhibiting less efficacy than lower doses. Probing this pharmacology in animal models we determined that the ability of SERDs to cross the blood brain barrier and attenuate ER signaling in the hypothalamus was a key differentiator of SERDs. In validated syngeneic models of breast cancer, we observed doses of fulvestrant having confirmed brain exposure stimulated tumor growth independent of tumor ER-status. We evaluated the ability of several next generation SERDs for their brain penetrance and demonstrated that SERD presence in the brain was associated with a stimulatory effect on tumor growth. Interestingly, administration of a low dose of 17b-estradiol (E2) together with a brain excluded SERD further repressed tumor growth, highlighting a potentially beneficial anti-tumor role for estrogen signaling in the brain. Furthermore, combination of a brain excluded SERM with E2 also resulted in increased tumor growth repression; thus, ER downregulation is dispensable for the cooperative activity observed for estrogens administered together with a peripheral ER antagonist. These data suggest that differences in tissue pharmacology, as opposed to differences in ability to degrade ER, is likely to be a major differentiator of ER modulators. Presentation: 6/3/2024

6471 Adult Height in Male Survivors of Childhood Cancer Treated with Aromatase Inhibitors and Growth Hormone

Abstract Disclosure: N.I. Pollock: None. M. Song: None. A. Wolf: None. Y. Li: None. C. Hawkes: None. N. Motamedi: None. M.R. Denburg: None. S. Mostoufi-Moab: None. Title: Adult Height in Male Survivors of Childhood Cancer Treated with Aromatase Inhibitors and Growth Hormone Objectives: Aromatase inhibitor (AI) therapy in combination with growth hormone (GH), or as monotherapy, may have a role in improving height outcomes in male pediatric patients with GH deficiency (GHD). The effectiveness of AI therapy in the childhood cancer survivors is not known. In this retrospective study, we assess adult height (AH) in childhood cancer survivors treated with AI combined with GH therapy compared to those treated with GH alone. Methods: This was a single center retrospective cohort study of male survivors of childhood cancer treated with GH for diagnosis of GHD between 2007 and 2023. We compared AH outcomes in males treated with GH alone or in combination with off-label use of AI. Demographic and clinical characteristics, including anthropometric measurements, endocrinopathies, and cancer history, were obtained from the medical record. AH was noted as height documented at fusion of growth plates or following 18 years of age. Differences in demographic, clinical, and treatment characteristics were assessed using univariate tests of association. Multivariable regression with stepwise selection was used to examine risk factors associated with AH. All statistical analyses were performed using Stata 18.0. Results: Ninety-two patients were included; 70 were treated with GH monotherapy and 22 with combination AI/GH. Median age at AI initiation was 13.6 years (IQR 12.3-14.3) versus 11.2 years (IQR 8.6-12.9) for GH (unpaired t-test p-value <0.01; 95% CI -4.01, -1.91). A greater proportion of patients in the AI/GH group had been treated with stem cell transplantation, abdominal radiation, total body irradiation, and cis-retinoic acid (Fisher’s exact p-value <0.01). There was no statistically significant difference in AH or AH Z-score between treatment groups, with the median AH Z-score in the AI/GH group -1.95 (IQR -3.11, -0.75) versus -1.39 (IQR -2.65, 0.11) in the GH group. In multivariable linear regression, history of radiation to the spine (β= -5.9, 95% CI -11.2, -0.6), height Z-score (β= 0.3, 95% CI 0.11, 0.46), BMI Z-score (β= 3.2, 95% CI 0.95, 5.5), and advanced bone age at GH or AI treatment initiation (β= -10.1, 95% CI -17.3, -2.9) were significantly associated with AH. Conclusions: Adjunctive treatment with AI and GH was not associated with increased AH outcomes in male survivors of childhood cancer compared to GH monotherapy. Future work is needed to determine optimal adjunctive medical therapy to maximize FAH impacted by cancer therapy for this patient population. Presentation: 6/3/2024

301P Changes in lipid-levels following aromatase inhibitor treatment in early postmenopausal breast cancer

301P Changes in lipid-levels following aromatase inhibitor treatment in early postmenopausal breast cancer

Impact of Aromatase Inhibitors Treatment Duration on Coronary Artery Calcification in Postoperative Patients With Breast Cancer

Impact of Aromatase Inhibitors Treatment Duration on Coronary Artery Calcification in Postoperative Patients With Breast Cancer

Capivasertib and fulvestrant for patients with hormone receptor-positive, HER2-negative advanced breast cancer (CAPItello-291): patient-reported outcomes from a phase 3, randomised, double-blind, placebo-controlled trial

CAPItello-291 is an ongoing phase 3 trial in which capivasertib-fulvestrant significantly improved progression-free survival versus placebo-fulvestrant in patients with hormone receptor-positive, HER2-negative advanced breast cancer who had relapse or disease progression during or after aromatase inhibitor treatment, in both the overall population and in patients with PIK3CA, AKT1, or PTEN-altered tumours. This study further explored patient-reported health-related quality of life (HRQOL), functioning, symptoms, and symptom tolerability in CAPItello-291. This phase 3, randomised, double-blind, placebo-controlled trial, which was conducted across 193 hospitals and cancer centres in 19 countries, enrolled women with any menopausal status or men, aged ≥18 years (≥20 years in Japan), with hormone receptor-positive, HER2-negative locally advanced or metastatic breast cancer who had relapse or disease progression during or after treatment with an aromatase inhibitor, with or without previous cyclin-dependent kinase (CDK) 4 or 6 inhibitor therapy. Patients had an Eastern Cooperative Oncology Group/WHO performance score of 0 or 1 and could have received up to two previous lines of endocrine therapy and up to one previous line of chemotherapy for advanced disease. Patients were randomly assigned (1:1) using block randomisation (stratified according to the presence or absence of liver metastases, previous use of a CDK4/6 inhibitor [yes vs no], and geographical region) to receive oral capivasertib 400 mg (twice daily for 4 days, followed by 3 days off) plus intramuscular fulvestrant 500 mg (every 14 days for the first three injections, then every 28 days) or placebo with matching fulvestrant dosing. The dual primary endpoint of the trial was investigator-assessed progression-free survival assessed both in the overall population and among patients with PIK3CA, AKT1, or PTEN-altered tumours. The EORTC Quality of Life Questionnaire 30-item core module (QLQ-C30) and breast module (QLQ-BR23), Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), and Patient Global Impression of Treatment Tolerability (PGI-TT) questionnaires were used to assess patient-reported outcomes. Evaluation of EORTC QLQ-C30 and EORTC QLQ-BR23 were secondary endpoints and evaluation of PRO-CTCAE and PGI-TT were pre-defined exploratory endpoints, and these endpoints are the subject of analysis in this Article. Data were collected at baseline and prespecified timepoints. Patient-reported outcomes were analysed in all randomly assigned patients with an evaluable baseline assessment and at least one evaluable post-baseline assessment. Change from baseline was assessed using mixed model with repeated measures for EORTC QLQ-C30 and summarised for QLQ-BR23. Time to deterioration was described using the Kaplan-Meier method. PGI-TT and PRO-CTCAE responses were summarised at each treatment cycle. Patient-reported outcomes were not prospectively powered for statistical comparison. The trial is registered with ClinicalTrials.gov, NCT04305496. Between June 2, 2020, and Oct 13, 2021, 901 patients were enrolled, of whom 708 patients were randomly assigned to receive capivasertib-fulvestrant (n=355) or placebo-fulvestrant (n=353). The median age of the patients was 59 years (IQR 51-67) in the capivasertib-fulvestrant group and 58 years (IQR 49-66) in the placebo-fulvestrant group. At data cutoff (Aug 15, 2022), the median duration of follow-up for progression-free survival in censored patients was 13·0 months (IQR 9·1-16·7) for capivasertib-fulvestrant and 12·7 months (IQR 2·0-16·4) for placebo-fulvestrant in the overall population. EORTC QLQ-C30 global health status/quality of life (GHS/QOL) scores were maintained from baseline and were similar between treatment groups throughout the study period (difference in mean change from baseline of -2·5 [95% CI -4·5 to -0·6] with capivasertib-fulvestrant vs -5·6 [-7·9 to -3·4] with placebo-fulvestrant; treatment difference 3·1 [95% CI 0·2 to 6·0]). Median time to deterioration in EORTC QLQ-C30 GHS/QOL was 24·9 months (95% CI 13·8 to not reached) in the capivasertib-fulvestrant group and 12·0 months (10·2 to 15·7) in the placebo-fulvestrant group (hazard ratio [HR] 0·70, 95% CI 0·53 to 0·92). Time to deterioration HRs for all EORTC QLQ-C30 and QLQ-BR23 subscale scores showed little difference between the treatment groups, except for diarrhoea, which was worse in the capivasertib-fulvestrant group than in the placebo-fulvestrant group (HR 2·75, 95% CI 2·01-3·81). In PRO-CTCAE symptom assessment, the proportion of patients reporting loose and watery stools "frequently" or "almost constantly" was 29% higher at cycle 1, day 15 in the capivasertib-fulvestrant group than in the placebo-fulvestrant group, decreasing at subsequent cycles. Other PRO-CTCAE-reported symptoms (rash, mouth or throat sores, itchy skin, and numbness or tingling in hands or feet) were absent or mild in most patients in both groups throughout treatment. According to the PGI-TT, most patients in both groups reported "not at all" or "a little bit" of bother from treatment side-effects. Patient-reported outcomes from CAPItello-291 demonstrated that capivasertib-fulvestrant delayed time to deterioration of GHS/QOL and maintained other dimensions of HRQOL (except symptoms of diarrhoea) similarly to fulvestrant. With the clinical efficacy and manageable safety profile, these exploratory results further support the positive benefit-risk profile of capivasertib-fulvestrant in this population. AstraZeneca.

Androgen receptor-mediated pharmacogenomic expression quantitative trait loci: implications for breast cancer response to AR-targeting therapy

BackgroundEndocrine therapy is the most important treatment modality of breast cancer patients whose tumors express the estrogen receptor α (ERα). The androgen receptor (AR) is also expressed in the vast majority (80–90%) of ERα-positive tumors. AR-targeting drugs are not used in clinical practice, but have been evaluated in multiple trials and preclinical studies.MethodsWe performed a genome-wide study to identify hormone/drug-induced single nucleotide polymorphism (SNP) genotype - dependent gene-expression, known as PGx-eQTL, mediated by either an AR agonist (dihydrotestosterone) or a partial antagonist (enzalutamide), utilizing a previously well characterized lymphoblastic cell line panel. The association of the identified SNPs-gene pairs with breast cancer phenotypes were then examined using three genome-wide association (GWAS) studies that we have published and other studies from the GWAS catalog.ResultsWe identified 13 DHT-mediated PGx-eQTL loci and 23 Enz-mediated PGx-eQTL loci that were associated with breast cancer outcomes post ER antagonist or aromatase inhibitors (AI) treatment, or with pharmacodynamic (PD) effects of AIs. An additional 30 loci were found to be associated with cancer risk and sex-hormone binding globulin levels. The top loci involved the genes IDH2 and TMEM9, the expression of which were suppressed by DHT in a PGx-eQTL SNP genotype-dependent manner. Both of these genes were overexpressed in breast cancer and were associated with a poorer prognosis. Therefore, suppression of these genes by AR agonists may benefit patients with minor allele genotypes for these SNPs.ConclusionsWe identified AR-related PGx-eQTL SNP-gene pairs that were associated with risks, outcomes and PD effects of endocrine therapy that may provide potential biomarkers for individualized treatment of breast cancer.

Clinical utility of an ultra-sensitive ctDNA NGS assay for the detection and monitoring in HR-positive, HER2-negative breast cancer.

e13076 Background: Breast cancer is the most diagnosed cancer in women globally, mainly as hormone receptor HR-positive, HER2-negative. While endocrine therapies have markedly improved clinical outcomes, the threat of disease progression persists. This study introduces an ultra-sensitive circulating tumor DNA (ctDNA) Next-Generation Sequencing (NGS) assay that was designed for in-depth genomic profiling of breast cancer patients undergoing endocrine therapy, aimed at detecting treatment resistance and monitoring disease progression. Methods: In this ongoing investigation, 46 patients with advanced HR-positive, HER2-negative breast cancer were enrolled, and plasma samples were collected subsequent to first-line aromatase inhibitor (AI) treatment and before the initiation of second-line treatment with fulvestrant. The study employed the PredicineCARE ULTRA, an ultra-sensitive liquid biopsy assay with a proprietary NGS panel and exceeds 100,000x coverage, allowing for the ultra-sensitive identification of genomic alterations, surpassing the detection capabilities of standard ctDNA NGS assays with approximately 20,000x coverage. Results: Within the cohort of 46 patients, the ultra-sensitive assay detected 193 somatic mutations, 95 gene copy number variants (CNVs), and a gene fusion involving FGFR3. The most commonly mutated genes, with a prevalence of 20% or more, were TP53 (33%), PIK3CA (26%), ATM (24%), ESR1 (22%), and BRCA2 (20%). These findings were benchmarked against results from a down-sampling algorithm designed to emulate ctDNA assays with 20,000x coverage. The ultra-sensitive assay revealed 31.3% more mutations (193 vs. 147) and 30.1% more CNVs. It was especially proficient in detecting mutations with allele frequencies (MAF) below 0.1%, identifying 10 additional mutations not observed at the standard ctDNA assay sensitivity, with the lowest MAF detected being 0.03% compared to the 0.1% threshold of the standard assay. This heightened sensitivity was evident in genes associated with targeted therapies and drug resistance, identifying 30.7% more variations in PIK3CA and 11.1% more in ESR1, with the lowest MAFs of 0.08% and 0.06%, respectively. The FGFR3-BAIAP2L1 gene fusion was also uniquely detected by the ultra-sensitive assay, with a MAF of 0.09%. Conclusions: The ultra-sensitive ctDNA NGS assay demonstrated superior detection of low-frequency mutations in HR-positive, HER2-negative breast cancer, significantly outperforming standard liquid biopsy assays. This enhanced sensitivity may offer profound implications for identifying more diagnostically positive patients who may benefit from targeted therapy such as PIK3CA and ESR1 inhibitors. This ultra-sensitive ctDNA assay will also enable early detection of treatment resistance and refined disease monitoring, potentially guiding more effective personalized therapies.

A randomized trial of topical cannabis balms for the treatment of aromatase inhibitor–associated musculoskeletal syndrome (AIMSS).

e24129 Background: Aromatase inhibitors (AIs) are commonly used for postmenopausal women with hormone receptor positive breast cancer. Nearly 2 of 3 women on AIs complain of AIMSS leading to poor adherence. Preclinical and clinical pilot data suggest topical cannabinoids can reduce inflammation in arthritis. Methods: We conducted a randomized controlled trial assessing the feasibility and acceptability of two different topical medical cannabis balms for AIMSS. Women with stage 1-3 breast cancer with AIMSS [scoring 4 or higher on at least one of the four screening Modified Score for the Assessment and Quantification of Chronic Rheumatoid Affectations of the Hands (M-SACRAH) questions] were eligible. Patients with skin lesions, use of any cannabis in prior 4 weeks, acupuncture, or plans to increase doses of other analgesics were excluded. Women were randomized 1:1 to cannabidiol (CBD) (2210mg CBD/ < 0.3% THC) vs delta-9-tetrahydrocannabinol (THC) (375mg THC/ < 20mg CBD) predominant balm. Participants enrolled in the Minnesota Medical Cannabis Program and were dispensed balms at state-registered dispensaries. 125cc of balm was applied 3 times daily to hands for 2 weeks. M-SACRAH, brief pain inventory (BPI), and NCI Patient Reported Outcomes Common Terminology Criteria for Adverse Events (PRO-CTCAE) measures were captured weekly. Results: 20 women were enrolled from one academic and one community oncology practice in Minnesota over a 10-month period. Reasons patients with AIMSS did not enroll included patient/clinician not interested, AIMSS not meeting M-SACRAH severity, and patient already using cannabis. Adherence to study protocol through week 2 was 85%. Mean age was 54 years, 85% White/15% Asian, 45% received adjuvant chemotherapy, and 50% reported no lifetime cannabis use. Participants reported improvement in M-SACRAH, BPI, and PRO-CTCAE pain scores from baseline to week 2 (Table 1). No skin toxicity was reported by patients. One patient discontinued balm due to greasy texture. Conclusions: Conducting a randomized trial of topical cannabis using state approved dispensaries is feasible. Both THC and CBD predominant topical balms are well tolerated and appear to reduce AIMSS severity in this pilot study of breast cancer survivors. Further confirmatory studies are warranted. Clinical trial information: NCT05935891 . [Table: see text]

Impact of aromatase inhibitors on mortality and hospitalization costs in patients with breast cancer: A National Inpatient Sample analysis 2020.

e13160 Background: Breast cancer is a significant public health concern globally, affecting millions of individuals each year. Aromatase inhibitors are a class of medications commonly used in the treatment of hormone receptor-positive breast cancer. The significance of the study lies in the impact of aromatase inhibitors on mortality and also healthcare-related costs for the treatment of breast cancer. Methods: The National Inpatient Sample database (2020) was used to identify adult patients with breast cancer using ICD-10 codes. Demographics (age, race, sex, region, and hospital size), co-morbidities, and hospitalization costs were compared between the two groups of patients: those who are on aromatase inhibitors and those who are not. The odds of mortality were analyzed. A p<0.05 was considered statistically significant. Results: Out of 166870 patients who had breast cancer, 12975(7.7%) were on aromatase inhibitors. The aromatase inhibitors group was relatively older (median age, 69.4 years vs 64 years) and predominantly white (71.50% vs 66%) compared to the non-aromatase inhibitors group. The prevalence of heart failure and osteoporosis was greater in the aromatase inhibitors group than in the non-aromatase inhibitors group. The adjusted odds ratio of mortality in the aromatase inhibitors group was 0.45, 95% CI (0.39-0.50, p<0.0001). Furthermore, the average total cost of hospitalization in the aromatase inhibitor group was $6426 less than the non-aromatase inhibitor group. Conclusions: Our study findings indicate that breast cancer patients treated with aromatase inhibitors experienced lower odds of mortality and lesser costs of hospitalization. However, the aromatase inhibitor group was found to have a higher prevalence of heart failure and osteoporosis. Hence, further research needs to be done on potential adverse effects and long-term effects of the aromatase inhibitors treatment.

Effectiveness of gonadotropin-releasing hormone agonists for ovarian function suppression in premenopausal patients with hormone receptor-positive breast cancer: a retrospective single-center real-world study

PurposeThis study evaluated the effectiveness of ovarian function suppression (OFS) of various gonadotropin-releasing hormone agonists (GnRHa) combined with aromatase inhibitors (AI) in premenopausal patients with hormone receptor-positive (HR-positive) breast cancer. Potential risk factors associated with insufficient OFS were analyzed.Patients and methodsPremenopausal HR-positive breast cancer patients who had received AI with GnRHa were studied retrospectively. Patients were divided into different groups according to monthly or trimonthly GnRHa schedules they received, and the effectiveness of OFS was compared between groups. Insufficient OFS was defined as at least one instance of estradiol ≥ 30 pg/ml. Patient data was gathered from medical records for this comparison.ResultsOf the 264 patients enrolled in this study, 117 were administered 3.6 mg of goserelin monthly (goserelin 1 M group), 63 received 3.75 mg of leuprorelin monthly (leuprorelin 1 M group) and 84 were given 11.25 mg of leuprorelin every three months (leuprorelin 3 M group). Overall, 7.20% experienced insufficient OFS. The incidence rates in the three GnRHa depot groups were 7.69%, 6.35%, and 7.14%, respectively, without a significant statistical difference (P = 0.900). Notably, younger patients exhibited a higher likelihood of insufficient OFS [OR = 0.900, 95%CI (0.824–0.982), P = 0.018].ConclusionInsufficient OFS remains a concern during GnRHa and AI treatment. The effectiveness of the three GnRHa depots commonly used in China seems comparable. Younger patients face a heightened risk of insufficient OFS.

Abstract PO2-09-04: Changes in an artificial intelligence model score for breast cancer detection (Transpara) with tamoxifen and aromatase inhibitor treatment

Abstract Artificial intelligence (AI) models applied to mammography have been shown to improve breast cancer (BC) detection and risk estimation. The Transpara AI detection system has been associated with short and longer-term risk of invasive BC. Whether Transpara can identify changes in the breast associated with tamoxifen (TAM) and aromatase inhibitor (AIs) treatment is unknown. We compare changes in the Transpara malignancy score in the unaffected breast of BC cases using TAM or AIs to those of untreated women without cancer. Cases and controls were sampled from the Mayo Clinic Rochester Breast Screening Practice. Eligible cases were women with breast cancer treated with TAM and/or AIs for at least 8 months who had full field digital (FFDM) mammograms within two years prior to start of treatment (pretreatment mammogram). Controls did not have BC, were not using TAM, AIs, or postmenopausal hormones, and had at least two FFDM screening mammograms. Transpara scores (1-10) were calculated for the contralateral breast in cases and a randomly selected side for controls. Two controls were matched to each case on menopausal status at both mammograms, time between mammograms (< 6 months) and baseline Transpara score (±2 units). Conditional logistic regression was used to assess the association of treatment (case (TAM/AIs) vs. control) with change in Transpara score between the pretreatment mammogram and the mammogram taken closest to 13 months later. Change was classified as having a decrease in Transpara score between the two mammograms vs. no change or an increase. Models were adjusted for age and Transpara score at pretreatment mammogram, and time between the two mammograms. We performed analyses on all women combined and stratified by time on treatment, menopausal status, and treatment type (TAM vs. AIs). A total of 134 cases were identified, with 53 on TAM (21 premenopausal and 32 postmenopausal) and 81 on AIs (postmenopausal); 268 controls were matched to the cases. Characteristics of the study population are summarized (Table). Most case mammograms were obtained within six months prior to treatment start [median 2.63 months (interquartile range (IQR), 1.62, 5.72)] and median time on TAM/AIs was 10.9 months (IQR, 8.03, 16.6) at time of second mammogram. The median absolute change in Transpara score between the two mammograms was similar in cases [0 (IQR, -2, 1)] vs. controls [0 (IQR, -1.25, 1)]; 40.3% of cases and 39.2% of controls had any decrease. Conditional logistic models found no evidence for an association between TAM/AIs and decrease in Transpara score [odds ratio (OR) = 1.07; 95% confidence interval (CI), 0.65, 1.78]. When stratified by median time on treatment (10.9 months), there was suggestion of a stronger association for those on treatment for a longer duration (OR = 1.21; 95% CI, 0.61, 2.40 for >10.9 months vs. OR = 0.96; 95% CI, 0.43, 2.13 for < 10.9 months) but these results were not statistically significant. Similarly, odds ratios were stronger in postmenopausal (OR = 1.18; 95% CI, 0.67, 2.07) compared to premenopausal (OR = 0.91; 95% CI, 0.24, 3.45) women, and for AIs (OR = 1.21, 95% CI, 0.64, 2.29) vs. TAM (OR = 0.93; 95% CI, 0.39, 2.22) but none of these results reached statistical significance. In summary, we found no association between treatment with TAM/AIs and change in Transpara score. However, our study had limited power. Also, longer time on treatment as well as investigation of AI-based scores trained directly to assess BC risk may be necessary to identify relevant changes. Citation Format: Yvonne Wang, Christopher Scott, Matthew Jensen, Dan Hursh, Kathleen Brandt, Aaron Norman, Fang Fang Wu, Stacey Winham, Karla Kerlikowske, Celine Vachon. Changes in an artificial intelligence model score for breast cancer detection (Transpara) with tamoxifen and aromatase inhibitor treatment [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-09-04.

Abstract PO4-19-09: Comparison of clinical efficacy between letrozole + ribociclib vs. Fulvestrant + letrozole + ribociclib in Hormone receptor positive, HER2 negative metastatic breast cancer – a randomized, phase 2 study (KCSG BR22-20)

Abstract Background The current standard first-line treatment in advanced or metastatic hormone receptor (HR) positive breast cancer is combination of aromatase inhibitor (AI) and cyclin D kinase-4/6 (CDK4/6) inhibitor. Emergence of ESR1 mutation is a key mechanism of resistance during first-line AI + CDK4/6 inhibitor treatment. Selective estrogen receptor downregulator (SERD) such as elacestrant or fulvestrant is suggested as second-line treatment, but the progression-free survival (PFS) outcome of second-line treatment is reported up to 3.78 months in patients who harbour ESR1 mutation. Recently, early switch of AI + CDK4/6 inhibitor to fulvestrant + CDK4/6 inhibitor at the point of rising ESR1 mutation showed prolongation of PFS up to 6 months, suggesting there may be a new strategy to overcome ESR1 mutation by modifying endocrine treatment. SWOG S0226 suggested that upfront fulvestrant + AI is feasible and associated with prolongation of PFS compared to AI alone. After CDK4/6 inhibitor has been introduced to standard treatment, there were no trials evaluating the role of AI + fulvestrant with CDK4/6 inhibitor. In this trial, we investigated triplet combination of AI + fulvestrant + CDK4/6 inhibitor as a treatment to overcome resistant mechanism such as development of ESR1 mutation when compared to current standard treatment of AI + CDK4/6 inhibitor as the first line treatment in HR positive advanced or metastatic breast cancer. Methods This study is a randomized, multicenter, open-label phase II trial comparing AI plus ribociclib versus AI, fulvestrant plus ribociclib in HR-positive advanced or metastatic breast cancer. De novo patients or patients with treatment-free interval (TFI) over 12 months after completion of adjuvant AI can be enrolled. If patients received adjuvant tamoxifen, patients with TFI less than 12 months can be also enrolled for the study. Prior endocrine treatment or cytotoxic chemotherapy at metastatic setting was not allowed. In cases of premenopausal women, gonadotropin releasing hormone agonist (GnRHa) is administered every 4 weeks with treatment. A total of 202 patients will be enrolled for 30 months, and 30 months of follow-up is planned after last-patient enrolment. Patients are randomized to 1:1, stratified based on the presence of visceral metastasis and previous administration of adjuvant AI. Study treatment of the control arm consists of letrozole 2.5mg daily with ribociclib 600mg (Day 1-Day 21 daily by month, 1 week off) until progression. In the experimental arm fulvestrant 500mg intramuscular injection is added (Day 1, Day 15, Day 29 and every 4 weeks thereafter) until progression. For exploratory analysis of ESR1 mutations, circulating tumor DNA (ctDNA) is collected at baseline, and then every 3 months thereafter. Primary endpoint is to evaluate the difference of 24-months PFS rate. Secondary endpoint included PFS, overall survival (OS), emergence and frequency of ESR1 mutation, overall response rate (ORR) and clinical benefit rate (CBR). The analysis is planned after completion of 30 months of follow-up, which provides approximately 90% power to detect superiority 24 months-PFS rate assumed by Kaplan-Meier curve of letrozole + fulvestrant + ribociclib versus letrozole + ribociclib using a log-rank test, assuming a hazard ratio of 0.64 at a two-sided alpha of 0.2. Citation Format: Jieun Lee, Su-Jin Koh, Jung Hye Kwon, Gun Min Kim, Jee Hung Kim, Ho Young Kim, Hee-Jun Kim, Keon-Uk Park, Kyong Hwa Park, Yeon Hee Park, Mi Sun Ahn, Hee Kyung Ahn, Gyeong-Won Lee, Kyoung Eun Lee, Kyung-Hun Lee, Moon Hee Lee, Sung Sook Lee, Jung Lim Lee, Kyung Hae Jung, Joo Young Jung, In Hae Park. Comparison of clinical efficacy between letrozole + ribociclib vs. Fulvestrant + letrozole + ribociclib in Hormone receptor positive, HER2 negative metastatic breast cancer – a randomized, phase 2 study (KCSG BR22-20) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-19-09.

Abstract PO2-17-03: Patient reported outcomes (PROs) and survival with toremifene versus aromatase inhibitors (AI) in patients with moderate/high-risk premenopausal hormone receptor (HR)-positive breast cancer: A real-world study

Abstract Background: The selective estrogen receptor modulator (SERM) toremifene, a synthetic analogue of tamoxifen, has shown similar efficacy to tamoxifen in patients with HR-positive breast cancer and is widely used in China for the treatment of premenopausal women with breast cancer. Multiple studies have confirmed the benefit of ovarian function suppression (OFS) combined with AI and SERMs in premenopausal women with HR-positive breast cancer. However, to date, there are no data comparing the efficacy and safety of toremifene plus OFS versus AI plus OFS. In this real-world study, we compared PROs and survival with toremifene or AI combined with OFS in patients with moderate/high-risk premenopausal HR-positive breast cancer. Methods: We enrolled premenopausal female patients with HR-positive, moderate/high-risk breast cancer who received OFS combined with toremifene or AI between January 1, 2010 and December 31, 2017 at the Breast Cancer Center of Sun Yat-sen Memorial Hospital. The primary endpoint was PROs, which were collected from January 1 to March 31, 2023, including the SF-36 and five-level EuroQol five-dimensional (EQ-5D-5L) questionnaires. Disease-free-survival (DFS) and safety were secondary endpoints. Associations between treatment group and SF-36 scores were evaluated using a Student’s t test and between treatment group and EQ-5D-5L scores using nonparametric tests. DFS was assessed using the Kaplan–Meier method and Cox regression. Results: A total of 392 patients were enrolled; 171 (43.6%) received toremifene and 221 (56.4%) received AI. Mean ± standard deviation scores for the role physical and general health dimensions of SF-36 were higher in the toremifene group versus the AI group (7.44±1.21 vs 7.15±1.48, P=0.034 and 22.90±3.95 vs 21.78±4.33, P=0.009, respectively). Scores on the anxiety/depression (AD) dimension of EQ-5D-5L were significantly different between the toremifene and AI treatment groups (mean rank: 184.14 vs 206.07, P=0.038); ‘no problems’ was selected by 49.7% and 37.1% of patients in the toremifene and AI groups, respectively. There were no significant differences in the other dimensions of SF-36 and EQ-5D-5L between the toremifene and AI groups (P>0.05). Similar estimated 5- and 8-year DFS rates were reported for the toremifene and AI groups; 96.5% (95% CI: 93.7-99.2) and 91.9% (95% CI: 88.2-95.5), and 87.4% (95% CI: 81.1-93.8) and 87.8% (95% CI: 81.1-94.4), respectively, and the hazard ratio for DFS was 0.75 (95% CI: 0.38-1.46), P=0.39. DFS was also comparable in the two treatment groups when stratified by HER2 status, age (≤40y vs >40y) and estrogen receptor expression level (≤20% vs >20%). Adverse event rates were generally similar in the two treatment groups, except for a higher rate of endometrial thickening (17.5% vs 1.8%, p< 0.001) and a lower rate of morning stiffness (7.6% vs 14.5%, p< 0.001) in the toremifene versus the AI group. Conclusion: Patients who received toremifene plus OFS had better role physical and general health dimensions on SF-36 and AD dimensions of EQ-5D-5L than those receiving AI plus OFS. There were no significant differences in 5- or 8-year DFS between the toremifene and AI groups. Both treatments were generally well tolerated. Citation Format: Yaping Yang, Fengxia Gan, Wenqian Yang, Yuan Xia, Qiang Liu, Chang Gong. Patient reported outcomes (PROs) and survival with toremifene versus aromatase inhibitors (AI) in patients with moderate/high-risk premenopausal hormone receptor (HR)-positive breast cancer: A real-world study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-17-03.

Abstract PO4-19-12: Trial in progress: An Observational Study to Examine Changes in Metabolic Syndrome Components in Patients With Breast Cancer Receiving (Neo)Adjuvant Aromatase Inhibitors

Abstract Background: (Neo) adjuvant systemic therapy has been shown to adversely impact metabolic health manifested as weight gain, dyslipidemia, and insulin resistance, which ultimately lead to the development of metabolic syndrome (MetS). MetS increases the risk of development for type 2 diabetes mellitus and cardiovascular disease and is associated with an increased risk of breast cancer recurrence, death due to breast cancer, and all-cause mortality. We have previously reported that 76% of metabolically healthy women receiving (neo) adjuvant chemotherapy will develop MetS at a median of 15 weeks. The impact of aromatase inhibitors (AIs) on metabolic health has not been systematically assessed in a longitudinal study. We hypothesize that AIs in the (neo) adjuvant setting will alter metabolic parameters and have embarked on a clinical trial to study this. Methods: This is a prospective observational study that will include: postmenopausal patients with newly diagnosed, early-stage hormone receptor (HR)-positive breast cancer with planned (neo)adjuvant treatment with an AI. Participants will be excluded if they have received or have planned treatment with (neo)adjuvant chemotherapy or are currently receiving antidiabetic medications or cholesterol-lowering agents. All patients will undergo a baseline assessment that includes: BMI, physical exam inclusive of blood pressure, waist circumference, assessment of body fat, lipid profile, insulin, metabolic biomarkers, and completion of the Functional Assessment of Cancer Therapy – Endocrine Symptoms (FACT-ES). Following institution of an AI, reassessment of the aforementioned tests will be repeated after 4 months and 12 months of therapy. The primary endpoint is the change in insulin resistance (as measured by HOMA-IR, homeostatic model assessment for insulin resistance) at 4 months. Secondary endpoints include the change in HOMA-IR at 12 months and the change in individual MetS components, metabolic biomarkers, anthropometric measurements, as well as FACT-ES scores from baseline to 4- and 12-months of AI treatment. The mean paired differences will be calculated for HOMA-IR measurements as well as for the secondary endpoints, and the 1-sided paired t-test will be used to test for statistical significance. One-way analysis of covariance will be used to compare means while adjusting for age, race/ethnicity, and BMI. Using a 1-sided paired t-test for the mean difference in HOMA-IR measurements from baseline to 4 months, we will have 80% power to detect an effect size of 0.405 with 40 patients (α = 0.05). Enrollment began in April 2023 and is ongoing. Contact alevee@coh.org for more information. Given the increased recognition of the importance of metabolic health in breast cancer outcomes, this data will inform future trials that focus on maintaining metabolic health in breast cancer survivors. Citation Format: Alexis LeVee, Nora Ruel, Victoria Seewaldt, Joanne Mortimer. Trial in progress: An Observational Study to Examine Changes in Metabolic Syndrome Components in Patients With Breast Cancer Receiving (Neo)Adjuvant Aromatase Inhibitors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-19-12.

Endothelial dysfunction in breast cancer survivors on aromatase inhibitors: changes over time

BackgroundBreast cancer is estimated to comprise about 290,560 new cases in 2022. Aromatase inhibitors (AIs) are recommended as adjuvant treatment for estrogen-receptor positive (ER+) breast carcinoma in postmenopausal women, which includes approximately two-thirds of all women with breast cancer. AIs inhibit the peripheral conversion of androgens to estrogen by deactivation of the aromatase enzyme, leading to a reduction in serum estrogen level in postmenopausal women with ER+ breast carcinoma. Estrogen is known for its cardiovascular (CV) protective properties through a variety of mechanisms including vasodilation of blood vessels and inhibition of vascular injury resulting in the prevention of atherosclerosis. In clinical trials and prospective cohorts, the long-term use of AIs can increase the risk for hypertension and hyperlipidemia. Studies demonstrate mixed results as to the impact of AIs on actual CV events and overall survival.MethodsA single arm longitudinal study of 14 postmenopausal women with ER+ breast cancer prescribed adjuvant AIs at the University of Minnesota (UMN). Subjects with a history of known tobacco use, hypertension, hyperlipidemia, and diabetes were excluded to eliminate potential confounding factors. Participants underwent routine labs, blood pressure assessments, and vascular testing at baseline (prior to starting AIs) and at six months. Vascular assessment was performed using the EndoPAT 2000 and HDI/PulseWave CR-2000 Cardiovascular Profiling System and pulse contour analysis on two occasions as previously described. Vascular measurements were conducted by one trained vascular technician. Assessments were performed in triplicate, and the mean indices were used for analyses. All subjects were on an AI at the follow-up visit. The protocol was approved by the UMN Institutional Review Board and all participants were provided written informed consent. Baseline and follow-up characteristics were compared using Wilcoxon signed-rank tests. Analyses were performed using R version 3.6.1 (R Foundation for Statistical Computing, Vienna, Austria).ResultsAfter six months of AI treatment, EndoPAT® ratio declined to a median 1.12 (Q1: 0.85, Q3: 1.86; p = 0.045; Figure 1) and median estradiol levels decreased to 2 pg/mL (Q1: 2, Q3: 3; p=0.052). There was no evidence of association between change in EndoPAT® and change in estradiol level (p = 0.91). There were no statistically significant changes in small or large arterial elasticity.ConclusionsWe hypothesize that long-term use of AI can lead to persistent endothelial dysfunction, and further investigation is necessary. In our study, patients were on AI for approximately 5-10 years. As a result, we do not have data on whether these changes, such as EndoPAT® ratio and the elasticity of small and large arterial, are reversible with discontinuation of AI. These findings set the stage for a larger study to more conclusively determine the association between AI exposure and cardiovascular outcomes. Further studies should evaluate for multivariate associations withmodifiable risk factors for CV disease.

A Cohort Study to Evaluate Genetic Predictors of Aromatase Inhibitor Musculoskeletal Symptoms: Results from ECOG-ACRIN E1Z11.

Aromatase inhibitor (AI)-associated musculoskeletal symptoms (AIMSS) are common and frequently lead to AI discontinuation. SNPs in candidate genes have been associated with AIMSS and AI discontinuation. E1Z11 is a prospective cohort study designed to validate the association between 10 SNPs and AI discontinuation due to AIMSS. Postmenopausal women with stage I to III hormone receptor-positive breast cancer received anastrozole 1 mg daily and completed patient-reported outcome measures to assess AIMSS (Stanford Health Assessment Questionnaire) at baseline, 3, 6, 9, and 12months. We estimated that 40% of participants would develop AIMSS and 25% would discontinue AI treatment within 12 months. Enrollment of 1,000 women with a fixed number per racial stratum provided 80% power to detect an effect size of 1.5 to 4. SNPs were found in ESR1 (rs2234693, rs2347868, and rs9340835), CYP19A1 (rs1062033 and rs4646), TCL1A (rs11849538, rs2369049, rs7158782, and rs7159713), and HTR2A (rs2296972). Of the 970 evaluable women, 43% developed AIMSS and 12% discontinued AI therapy within 12months. Although more Black and Asian women developed AIMSS than White women (49% vs. 39%, P=0.017; 50% vs. 39%, P=0.004, respectively), the AI discontinuation rates were similar across groups. None of the SNPs were significantly associated with AIMSS or AI discontinuation in the overall population or in distinct cohorts. The OR for rs2296972 (HTR2A) approached significance for developing AIMSS. We were unable to prospectively validate candidate SNPs previously associated with AI discontinuation due to AIMSS. Future analyses will explore additional genetic markers, patient-reported outcome predictors of AIMSS, and differences by race.

Circulating tumour DNA dynamics during alternating chemotherapy and hormonal therapy in metastatic breast cancer: the ALERT study

PurposeAlthough changes in circulating tumour DNA (ctDNA) in breast cancer are well described, the kinetics of their fluctuations has not been described over short timescales. We investigated ctDNA dynamics during alternating cycles of chemotherapy and hormonal treatment in pre-treated patients with oestrogen receptor-positive metastatic breast cancer.MethodsPatients received alternating, 9-week cycles of eribulin and aromatase inhibitors (AIs). The clinical primary endpoint, progression-free survival (PFS), was monitored at 3, 6 and 9 months; secondary endpoints, clinical benefit rate (CBR), safety and tolerability profiles, were also assessed. Importantly, ctDNA fluctuations were monitored using the Oncomine™ Breast cfDNA assay to test whether biomarkers may change rapidly between chemotherapy and aromatase inhibitor (AI) treatment in the setting of advanced breast cancer, potentially reflecting disease dynamics.ResultsThe median PFS was 202 days (95% CI: 135-undefined) and 235 days (95% CI: 235-undefined) at 6 and 9 months, respectively, with a 50% CBR at both 6 and 9 months. Dynamic changes in ctDNA were observed in short timescales between chemotherapy and AI treatment and support the clinical benefit (CB) seen in individual patients and, critically, appear informative of acquired resistance in real time.ConclusionChanges in ctDNA can occur rapidly and reflect changes in patients’ clinical tumour responses (NCT02681523).