Impact of the Breast Cancer Index for Extended Endocrine Decision-Making: First Results of the Prospective BCI Registry Study.

BACKGROUND: The Breast Cancer Index (BCI) test assay provides an individualized risk of late distant recurrence (5-10 years) and predicts the likelihood of benefitting from extended endocrine therapy (EET) in hormone receptor-positive early-stage breast cancer. This analysis aimed to assess the impact of BCI on EET decision-making in current clinical practice. METHODS: The BCI Registry study evaluates long-term outcomes, decision impact, and medication adherence in patients receiving BCI testing as part of routine clinical care. Physicians and patients completed pre-BCI and post-BCI test questionnaires to assess a range of questions, including physician decision-making and confidence regarding EET; patient preferences and concerns about the cost, side effects, drug safety, and benefit of EET; and patient satisfaction regarding treatment recommendations. Pre-BCI and post-BCI test responses were compared using McNemar's test and Wilcoxon signed rank test. RESULTS: Pre-BCI and post-BCI questionnaires were completed for 843 physicians and 823 patients. The mean age at enrollment was 65 years, and 88.4% of patients were postmenopausal. Of the tumors, 74.7% were T1, 53.4% were grade 2, 76.0% were N0, and 13.8% were HER2-positive. Following BCI testing, physicians changed EET recommendations in 40.1% of patients (P<.0001), and 45.1% of patients changed their preferences for EET (P<.0001). In addition, 38.8% of physicians felt more confident in their recommendation (P<.0001), and 41.4% of patients felt more comfortable with their EET decision (P<.0001). Compared with baseline, significantly more patients were less concerned about the cost (20.9%; P<.0001), drug safety (25.4%; P=.0014), and benefit of EET (29.3%; P=.0002). CONCLUSIONS: This analysis in a large patient cohort of the BCI Registry confirms and extends previous findings on the significant decision-making impact of BCI on EET. Incorporating BCI into clinical practice resulted in changes in physician recommendations, increased physician confidence, improved patient satisfaction, and reduced patient concerns regarding the cost, drug safety, and benefit of EET.

Targeting HER2/HER3 co-mutations in metastatic breast cancer: Case reports of exceptional responders to trastuzumab and pertuzumab therapy.

BACKGROUND: Overexpression of HER2 plays an important role in cancer progression and is the target of multiple therapies in HER2-positive breast cancer. Recent studies have also highlighted the presence of activating mutations in HER2, and HER3 that are predicted to enhance HER2 downstream pathway activation in a HER2-dependent manner. METHODS: In this report, we present two exceptional responses in hormone receptor-positive, HER2-nonamplified, HER2/HER3 co-mutated metastatic breast cancer patients who were treated with the anti-HER2-directed monoclonal antibodies, trastuzumab and pertuzumab. RESULTS: Both patients acheived exceptional responses to treatment, suggesting that combined trastuzumab, pertuzumab, and endocrine therapy could be a highly effective therapy for these patients and our observations could help prioritize trastuzumab deruxtecan as an early therapeutic choice for patients whose cancers have activating mutations in HER2.

Activity and safety of enobosarm, a novel, oral, selective androgen receptor modulator, in androgen receptor-positive, oestrogen receptor-positive, and HER2-negative advanced breast cancer (Study G200802): a randomised, open-label, multicentre, multinational, parallel design, phase 2 trial.

BACKGROUND: The androgen receptor is a tumour suppressor in oestrogen receptor-positive breast cancer. The activity and safety of enobosarm, an oral selective androgen receptor modulator, was evaluated in women with oestrogen receptor (ER)-positive, HER2-negative, and androgen receptor (AR)-positive disease. METHODS: Women who were postmenopausal (aged ≥18 years) with previously treated ER-positive, HER2-negative, locally advanced or metastatic breast cancer with an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled in a randomised, open-label, multicentre, multinational, parallel design, phase 2 trial done at 35 cancer treatment centres in nine countries. Participants were stratified on the setting of immediately preceding endocrine therapy and the presence of bone-only metastasis and randomly assigned (1:1) to 9 mg or 18 mg oral enobosarm daily using an interactive web response system. The primary endpoint was clinical benefit rate at 24 weeks in those with centrally confirmed AR-positive disease (ie, the evaluable population). This trial is registered with ClinicalTrials.gov (NCT02463032). FINDINGS: Between Sept 10, 2015, and Nov 28, 2017, 136 (79%) of 172 patients deemed eligible were randomly assigned to 9 mg (n=72) or 18 mg (n=64) oral enobosarm daily. Of these 136 patients, 102 (75%) patients formed the evaluable population (9 mg, n=50; 18 mg, n=52). The median age was 60·5 years (IQR 52·3-69·3) in the 9 mg group and 62·5 years (54·0-69·3) in the 18 mg group. The median follow-up was 7·5 months (IQR 2·9-14·1). At 24 weeks, 16 (32%, 95% CI 20-47) of 50 in the 9 mg group and 15 (29%, 17-43) of 52 in the 18 mg group had clinical benefit. Six (8%) of 75 patients who received 9 mg and ten (16%) of 61 patients who received 18 mg had grade 3 or grade 4 drug-related adverse events, most frequently increased hepatic transaminases (three [4%] of 75 in the 9 mg group and two [3%] of 61 in the 18 mg group), hypercalcaemia (two [3%] and two [3%]), and fatigue (one [1%] and two [3%]). Four deaths (one in the 9 mg group and three in the 18 mg group) were deemed unrelated to the study drug. INTERPRETATION: Enobosarm has anti-tumour activity in patients with ER-positive, HER2-negative advanced breast cancer, showing that AR activation can result in clinical benefit, supporting further clinical investigation of selective AR activation strategies for the treatment of AR-positive, ER-positive, HER2-negative advanced breast cancer. FUNDING: GTx.

Long-Term Follow-Up of the Anthracyclines in Early Breast Cancer Trials (USOR 06-090, NSABP B-46-I/USOR 07132, and NSABP B-49 [NRG Oncology]).

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The primary joint efficacy analysis of the Anthracyclines in Early Breast Cancer (ABC) trials reported in 2017 failed to demonstrate nonanthracycline adjuvant therapy was noninferior to anthracycline-based regimens in high-risk, early breast cancer. Full analyses of the studies had proceeded when the prespecified futility boundary was crossed at a planned futility analysis for the ability to demonstrate noninferiority of a nonanthracycline regimen with continued follow-up. These results were presented with 3.3 years of median follow-up. This manuscript reports results of the final analyses of the study efficacy end points conducted with 6.9 years of median follow-up. Long-term analysis of invasive disease-free survival (IDFS), the primary end point of the ABC trials, remains consistent with the original results, as noninferiority of the nonanthracycline regimens could not be declared on the basis of the original criteria. The secondary end point of recurrence-free interval, which excluded deaths not due to breast cancer as events, favored anthracycline-based regimens, and tests for heterogeneity were significant for hormone receptor status (P = .02) favoring anthracycline regimens for the hormone receptor-negative cohorts. There was no difference in overall survival, and review of the type of IDFS events in the groups suggested reductions in cancer recurrences achieved with anthracycline regimens were offset by late leukemias and deaths unrelated to breast cancer.

Health-related quality of life in the phase III ASCENT trial of sacituzumab govitecan versus standard chemotherapy in metastatic triple-negative breast cancer.

BACKGROUND: The antibody-drug conjugate sacituzumab govitecan (SG) prolongs progression-free survival and overall survival in patients with refractory/relapsed metastatic triple-negative breast cancer (mTNBC). Here, we investigated its effect on health-related quality of life (HRQoL). METHODS: This analysis was based on the open-label phase III ASCENT trial (NCT02574455). Adults with refractory/relapsed mTNBC who had received ≥2 prior systemic therapies (≥1 in the metastatic setting) were randomised 1:1 to SG or treatment of physician's choice (TPC; capecitabine, eribulin, vinorelbine, or gemcitabine). HRQoL was assessed on day 1 of each treatment cycle using the EORTC QLQ-C30. Score changes from baseline were analysed using linear mixed-effect models for repeated measures. Stratified Cox regressions evaluated time to first clinically meaningful change of HRQoL. RESULTS: The analysis population comprised 236 patients randomised to SG and 183 to TPC. For global health status (GHS)/QoL, physical functioning, fatigue, and pain, changes from baseline were superior for SG versus TPC. Compared with TPC, SG was inferior regarding changes from baseline for nausea/vomiting and diarrhoea but non-inferior for other QLQ-C30 domains. Median time to first clinically meaningful worsening was longer for SG than for TPC for physical functioning (22.1 versus 12.1 weeks, P < 0.001), role functioning (11.4 versus 7.1 weeks, P < 0.001), fatigue (7.7 versus 6.0 weeks, P < 0.05), and pain (21.6 versus 9.9 weeks, P < 0.001). CONCLUSIONS: SG was generally associated with greater improvements and delayed worsening of HRQoL scores compared with TPC. This supports the favourable profile of SG as an mTNBC treatment.

A multidisciplinary approach to optimizing care of patients treated with alpelisib.

PURPOSE: The oral, α-specific phosphatidylinositol-3-kinase (PI3Kα) inhibitor alpelisib is the first PI3K inhibitor approved for the treatment of advanced breast cancer. As alpelisib is a relatively new therapeutic option, specific guidance and a multidisciplinary approach are needed to provide optimal patient care. The primary objective of this manuscript is to provide comprehensive guidance on minimizing and managing adverse events (AEs) for patients with advanced breast cancer who are receiving alpelisib. METHODS: Clinical studies, prescribing information, published literature, and relevant guidelines were reviewed to provide recommendations on the prevention and management of alpelisib-associated AEs. RESULTS: The most common AEs associated with alpelisib in the phase 3 SOLAR-1 trial were hyperglycemia and rash (which are considered on-target effects of PI3Kα inhibition) and gastrointestinal AEs, including diarrhea, nausea, and decreased appetite. These AEs require regular monitoring, early recognition, and prompt initiation of appropriate treatment. In addition, there are effective strategies to reduce the onset and severity of frequently observed AEs-in particular, onset of hyperglycemia and rash may be reduced by lifestyle changes (such as reduced intake of carbohydrates and regular exercise) and antihistamine prophylaxis, respectively. To reduce risk of severe hyperglycemia, it is essential to achieve adequate glycemic control prior to initiation of alpelisib treatment. CONCLUSION: Overall, alpelisib-associated AEs are generally manageable with prompt recognition, regular monitoring, and appropriate intervention, preferably with a multidisciplinary approach.

Real-world Evidence of Diagnostic Testing and Treatment Patterns in US Patients With Breast Cancer With Implications for Treatment Biomarkers From RNA Sequencing Data.

OBJECTIVE/BACKGROUND: We performed a retrospective analysis of longitudinal real-world data (RWD) from patients with breast cancer to replicate results from clinical studies and demonstrate the feasibility of generating real-world evidence. We also assessed the value of transcriptome profiling as a complementary tool for determining molecular subtypes. METHODS: De-identified, longitudinal data were analyzed after abstraction from records of patients with breast cancer in the United States (US) structured and stored in the Tempus database. Demographics, clinical characteristics, molecular subtype, treatment history, and survival outcomes were assessed according to strict qualitative criteria. RNA sequencing and clinical data were used to predict molecular subtypes and signaling pathway enrichment. RESULTS: The clinical abstraction cohort (n = 4000) mirrored the demographics and clinical characteristics of patients with breast cancer in the US, indicating feasibility for RWE generation. Among patients who were human epidermal growth factor receptor 2-positive (HER2+), 74.2% received anti-HER2 therapy, with ∼70% starting within 3 months of a positive test result. Most non-treated patients were early stage. In this RWD set, 31.7% of patients with HER2+ immunohistochemistry (IHC) had discordant fluorescence in situ hybridization results recorded. Among patients with multiple HER2 IHC results at diagnosis, 18.6% exhibited intra-test discordance. Through development of a whole-transcriptome model to predict IHC receptor status in the molecular sequenced cohort (n = 400), molecular subtypes were resolved for all patients (n = 36) with equivocal HER2 statuses from abstracted test results. Receptor-related signaling pathways were differentially enriched between clinical molecular subtypes. CONCLUSIONS: RWD in the Tempus database mirrors the overall population of patients with breast cancer in the US. These results suggest that real-time, RWD analyses are feasible in a large, highly heterogeneous database. Furthermore, molecular data may aid deficiencies and discrepancies observed from breast cancer RWD.

Neratinib: an option for HER2-positive metastatic breast cancer.

Metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer is currently incurable. The primary goals of treatment are to prolong survival while optimizing quality of life. Several agents are now available in this setting, including neratinib, tucatinib, ado-trastuzumab emtansine, and trastuzumab deruxtecan. Neratinib in combination with capecitabine was recently approved for the treatment of adult patients with advanced or metastatic breast cancer who have received 2 or more prior anti-HER2-based regimens in the metastatic setting. Neratinib is an oral pan-HER inhibitor that binds covalently to the kinase site, providing irreversible binding. Phase 3 data showed that the combination of neratinib plus capecitabine improved progression-free survival vs lapatinib plus capecitabine. The duration of response was longer among patients in the neratinib arm. Neratinib plus capecitabine was also active against brain metastases associated with refractory, HER2-positive breast cancer, and this combination is listed in guidelines from the National Comprehensive Cancer Network for this indication. When combined with fulvestrant, neratinib demonstrated efficacy in patients with HER2-positive breast cancer, regardless of their hormone receptor status. Ongoing trials are evaluating the ability of neratinib to treat brain metastases, as well as the efficacy and safety of the triplet combination of neratinib, fulvestrant, and trastuzumab in this setting.

Neratinib in the early-stage/extended adjuvant breast cancer patient.

Breast cancer is the most common tumor type observed in women in the United States. The majority of patients are diagnosed at an early stage, but the disease often recurs after initial treatment. Human epidermal growth factor receptor 2 (HER2) gene amplification is present in approximately 20% to 25% of breast tumors and is associated with invasive disease and an aggressive phenotype. The addition of anti-HER2 therapy to chemotherapy has significantly improved the prognosis for patients with these aggressive tumors. However, despite the dramatic advances in survival achieved by targeting HER2, patients with these tumors are still at risk for recurrence after initial treatment. In an effort to address the risk for recurrence, recent clinical trials have evaluated the efficacy and safety of anti-HER2 antibodies and HER2 tyrosine kinase inhibitors as adjuvant or extended adjuvant therapy. Meaningful reductions have been observed in the risk for invasive and distant recurrence, particularly in certain HER2-positive breast cancer subpopulations. To optimize adjuvant treatment, therapies should be prescribed for patient subpopulations based on factors such as underlying risk profile, response to initial therapy, and patient preference. Neratinib is a small-molecule, irreversible tyrosine kinase inhibitor of HER1, HER2, and HER4 that penetrates the blood-brain barrier. This monograph examines neratinib in the setting of early-stage/extended adjuvant breast cancer, with a focus on clinical trial data, the mechanism of action, and ways to optimize clinical use.

Systematic literature review of clinical trials of endocrine therapies for premenopausal women with metastatic HR+ HER2- breast cancer.

Several endocrine-based therapies have recently been evaluated as treatments for premenopausal women with hormone-receptor-positive/human-epidermal-growth-factor-receptor 2 negative (HR+/HER2-) metastatic breast cancer (mBC). We conducted a systematic review and assessed the feasibility of an indirect treatment comparison (ITC) to characterize the comparative efficacy of endocrine-based therapies in this setting. A systematic literature review (SLR) of Medline, EMBASE, Cochrane Library and key conferences was performed to identify randomized clinical trials (RCTs) satisfying the following criteria: (a) included pre/perimenopausal women with HR+/HER2- mBC, (b) included endocrine-based therapies, (c) reported efficacy, safety, or quality of life outcomes, and (d) was published in 2007 or later (when HER2 testing was standardized). The clinical and methodological similarities across trials were assessed to evaluate the feasibility of an ITC. Four RCTs (PALOMA-3, MONARCH-2, KCSG BR10-04 and MONALEESA-7) and eight regimens (palbociclib + fulvestrant + goserelin, fulvestrant + goserelin, abemaciclib + fulvestrant + gonadotropin-releasing hormone agonist [GnRHa], fulvestrant + GnRHa, anastrozole + goserelin, goserelin, ribociclib + NSAI/tamoxifen + goserelin and NSAI/tamoxifen + goserelin) were selected. MONALEESA-7 was the only phase 3 trial investigating endocrine-based therapies as first-line in only pre/perimenopausal women with HR+/HER2- mBC; the other three trials focused on the ET-failure setting and their pre/perimenopausal populations were relatively small. ITCs were methodologically unfeasible due to critical differences in treatment settings and lack of common comparators across trials. Therefore, we were not able to characterize the relative efficacy of the different endocrine-based therapies available in the premenopausal HR+/HER2- mBC setting. This systematic review provides a comprehensive assessment of the available trial evidence on the efficacy and safety of endocrine-based therapies for premenopausal women with HR+/HER2- mBC. Only four trials have reported relevant data in this setting, and MONALEESA-7 is currently the only trial focused on premenopausal HR+ HER2- mBC in the first-line setting.

Evaluation of Miracle Mouthwash plus Hydrocortisone Versus Prednisolone Mouth Rinses as Prophylaxis for Everolimus-Associated Stomatitis: A Randomized Phase II Study.

BACKGROUND: Mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis (mIAS) is a frequent adverse event (AE) associated with mTOR inhibitor therapy and can impact treatment adherence. The objectives are to evaluate two steroid-based mouthrinses for preventing/ameliorating mIAS in patients with metastatic breast cancer (MBC) treated with everolimus. MATERIALS AND METHODS: This prospective, randomized phase II study enrolled 100 postmenopausal patients with hormone receptor-positive MBC within the US Oncology Network who were initiating therapy with an aromatase inhibitor + everolimus (AIE; 10 mg/day). Patients were randomized to prophylactic therapy with one of two oral rinses (Arm 1: Miracle Mouthwash [MMW] 480 mL recipe: 320 mL oral Benadryl [diphenhydramine; Johnson & Johnson, New Brunswick, NJ, USA], 2 g tetracycline, 80 mg hydrocortisone, 40 mL nystatin suspension, water; or Arm 2: prednisolone [P] 15 mg/5 mL oral solution, 1.8% alcohol). Patients were instructed to swish/expectorate 10 mL of the assigned rinse for 1-2 minutes four times daily starting with day 1 of AIE treatment, for the first 12 weeks. RESULTS: A total of 100 patients received treatment (49 MMW; 51 P). The incidence of stomatitis/oral AEs during the first 12 weeks was 35% (n = 17/49) and 37% (19/51) in the MMW and P arms, respectively. The incidence of grade 2 oral AEs was 14% (7/49) and 12% (6/51) with MMW or P, respectively. There were two grade 3 oral AEs (MMW arm) and no grade 4 events. There was one everolimus dose reduction (MMW) and six dose delays (four MMW, two P) and one dose reduction + delay (MMW) during the first 12 weeks of treatment. No patients stopped steroid mouthwash therapy because of rinse-related toxicity. CONCLUSION: Prophylactic use of steroid-containing oral rinses can prevent/ameliorate mIAS in patients with MBC treated with AIE. MMW + hydrocortisone is an affordable option, as is dexamethasone oral rinse. IMPLICATIONS FOR PRACTICE: This prospective phase-II study showed that two steroid-containing mouthrinses substantially reduced incidences of all-grade and grade ≥2 stomatitis and related oral adverse events (AEs), and the number of everolimus dose-delays and/or dose-reduction in metastatic breast cancer (MBC) patients receiving everolimus treatment plus an aromatase inhibitor. Both oral rinses were well tolerated and demonstrated similar efficacy. Prophylactic use of steroid mouth rinse provides a cost-effective option that substantially decreases the incidence and severity of mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis and related oral AEs as well as the need for dose modification in MBC patients undergoing treatment with an mTOR inhibitor.

Genomic Alterations Associated with Recurrence and TNBC Subtype in High-Risk Early Breast Cancers.

The identification of early breast cancer patients who may benefit from adjuvant chemotherapy has evolved to include assessment of clinicopathologic features such as tumor size and nodal status, as well as several gene-expression profiles for ER-positive, HER2-negative cancers. However, these tools do not reliably identify patients at the greatest risk of recurrence. The mutation and copy-number landscape of triple-negative breast cancer (TNBC) subtypes defined by gene expression is also largely unknown, and elucidation of this landscape may shed light on novel therapeutic opportunities. The USO01062 phase III clinical trial of standard chemotherapy (with or without capecitabine) enrolled a cohort of putatively high-risk patients based on clinical features, yet only observed a 5-year disease-free survival event rate of 11.6%. In order to uncover genomic aberrations associated with recurrence, a targeted next-generation sequencing panel was used to compare tumor specimens from patients who had a recurrence event with a matched set who did not. The somatic mutation and copy-number alteration landscapes of high-risk early breast cancer patients were characterized and alterations associated with relapse were identified. Tumor mutational burden was evaluated but was not prognostic in this study, nor did it correlate with PDL1 or CD8 gene expression. However, TNBC subtypes had substantial genomic heterogeneity with a distinct pattern of genomic alterations and putative underlying driver mutations. IMPLICATIONS: The present study uncovers a compendium of genomic alterations with utility to more precisely identify high-risk patients for adjuvant trials of novel therapeutic agents.

A Four-gene Decision Tree Signature Classification of Triple-negative Breast Cancer: Implications for Targeted Therapeutics.

The molecular complexity of triple-negative breast cancers (TNBCs) provides a challenge for patient management. We set out to characterize this heterogeneous disease by combining transcriptomics and genomics data, with the aim of revealing convergent pathway dependencies with the potential for treatment intervention. A Bayesian algorithm was used to integrate molecular profiles in two TNBC cohorts, followed by validation using five independent cohorts (n = 1,168), including three clinical trials. A four-gene decision tree signature was identified, which robustly classified TNBCs into six subtypes. All four genes in the signature (EXO1, TP53BP2, FOXM1, and RSU1) are associated with either genomic instability, malignant growth, or treatment response. One of the six subtypes, MC6, encompassed the largest proportion of tumors (∼50%) in early diagnosed TNBCs. In TNBC patients with metastatic disease, the MC6 proportion was reduced to 25%, and was independently associated with a higher response rate to platinum-based chemotherapy. In TNBC cell line data, platinum sensitivity was recapitulated, and a sensitivity to the inhibition of the phosphatase PPM1D was revealed. Molecularly, MC6-TNBCs displayed high levels of telomeric allelic imbalances, enrichment of CD4+ and CD8+ immune signatures, and reduced expression of genes negatively regulating the MAPK signaling pathway. These observations suggest that our integrative classification approach may identify TNBC patients with discernible and theoretically pharmacologically tractable features that merit further studies in prospective trials.