Management Of HER2-positive Breast Cancer Research Articles

Prognostic significance of ctDNA mutation analysis in patients with HER2-positive breast cancer undergoing neoadjuvant chemotherapy.

e12654 Background: Neoadjuvant chemotherapy (NACT) combined with dual anti-HER2 agents followed by surgical resection is the standard treatment for stage II-III HER2- positive breast cancer (BC). Despite the availability of effective therapies such as ado-trastuzumab emtansine (T-DM1) and neratinib, identifying patients at high risk of disease recurrence remains challenging. To evaluate whether circulating tumor DNA (ctDNA) can be used as a biomarker to assess treatment response in patients with HER2-positive EBC treated with neoadjuvant anti-HER2 therapy. ctDNA burden can serve as a useful determinant for escalating or de-escalating (neo)adjuvant strategy in EBC patients. This study aimed to assess the role of ctDNA mutation analysis using low-pass whole-genome sequencing (lpWGS) and whole exome sequencing (WES) in evaluating blood copy-number burden (bCNB), genomic alterations, mutational signatures, blood tumor mutational burden (bTMB), and minimal residual disease (MRD) monitoring. Methods: A total of 46 HER2-positive BC patients who underwent NACT combined with dual anti-HER2 agents and surgical resection were enrolled, including 28 clinical stage II and 17 III patients. Plasma samples were collected at four time points: before NACT, after 3 cycles, at the completion of NACT, and after surgery. lpWGS was utilized to assess bCNB, while WES was performed to evaluate genomic alterations, mutational signatures, and bTMB. Mutations selected from the baseline sample were monitored for MRD. In cases where lpWGS yielded negative results, targeted NGS sequencing was conducted. Somatic mutations are identified by whole exome sequencing across 20,000 genes (with boosted sequencing coverage for 600 cancer-related genes). Between 4-50 personalized somatic mutations or fusions are selected for each patient. This personalized panel together with a fixed MRD core panel is utilized for MRD detection and monitoring. Results: Among the enrolled patients, nodal metastasis was observed in 29 patients and 29 were hormone receptor-positive, and 36 achieved pCR (78.2%). Positive ctDNA was detected 58.8% of patients. Higher nodal stage was associated with ctDNA positivity at baseline. MRD positivity after chemotherapy was observed in 4 patients and 2 patients achieved pCR TP53 was the most frequently altered gene, followed by PIK3CA, MAP3K1, REV3L, MYC, MAP2K4, ERBB3, ATRX, ATM and ALK. This pattern is comparable to that observed in previous studies on BC. Non-PCR patients commonly exhibit MAP3K1 and MAP2K4 alteration is their ctDNA. Conclusions: The identification of MRD, regardless of pCR status, can be valuable for risk stratification and personalized treatment decision-making. Further studies are warranted to validate these findings and explore the clinical implications of ctDNA mutation analysis in HER2-positive BC management.

Targeting HER2-positive breast cancer cells by a combination of dasatinib and BMS-202: Insight into the molecular pathways

BackgroundRecent investigations have reported the benefits of using a tyrosine kinase inhibitor, dasatinib (DA), as well as programmed death-ligand 1 (PD-L1) inhibitors in the management of several solid tumors, including breast cancer. Nevertheless, the outcome of the combination of these inhibitors on HER2-positive breast cancer is not explored yet.MethodsHerein, we investigated the impact of DA and PD-L1 inhibitor (BMS-202) combination on HER2-positive breast cancer cell lines, SKBR3 and ZR75.ResultsOur data reveal that the combination significantly inhibits cell viability of both cancer cell lines as compared to monotreatment. Moreover, the combination inhibits epithelial-mesenchymal transition (EMT) progression and reduces cancer cell invasion by restoring E-cadherin and β-catenin expressions and loss of vimentin, major biomarkers of EMT. Additionally, the combination reduces the colony formation of both cell lines in comparison with their matched control. Also, the combination considerably inhibits the angiogenesis of the chorioallantoic membrane model compared with monotreatment. Molecular pathway analysis of treated cells shows that this combination blocks HER2, AKT, β-catenin, and JNK1/2/3 activities.ConclusionOur findings implicate that a combination of DA and BMS-202 could have a significant impact on the management of HER2-positive breast cancer.

Systemic Therapies for HER2-Positive Advanced Breast Cancer.

Despite recent advances, HER2-positive advanced breast cancer (ABC) remains a largely incurable disease, with resistance to conventional anti-HER2 drugs ultimately unavoidable for all but a small minority of patients who achieve an enduring remission and possibly cure. Over the past two decades, significant advances in our understanding of the underlying molecular mechanisms of HER2-driven oncogenesis have translated into pharmaceutical advances, with the developing of increasingly sophisticated therapies directed against HER2. These include novel, more potent selective HER2 tyrosine kinase inhibitors (TKIs); new anti-HER2 antibody-drug conjugates; and dual epitope targeting antibodies, with more advanced pharmacological properties and higher affinity. With the introduction of adjuvant T-DM1 for incomplete responders to neoadjuvant therapy, fewer patients are relapsing, but for those who do relapse, disease that may be resistant to standard first- and second-line therapies requires new approaches. Furthermore, the risk of CNS relapse has not been abrogated by current (neo)adjuvant strategies; therefore, current research efforts are being directed towards this challenging site of metastatic disease. In this article, we review the currently available clinical data informing the effective management of HER2-positive breast cancer beyond standard first-line therapy with pertuzumab, trastuzumab, and taxanes, and the management of relapse in patients who have already been exposed to both these agents and T-DM1 for early breast cancer (EBC). We additionally discuss novel anti-HER2 targeted agents and combinations in clinical trials, which may be integrated into standard treatment paradigms in the future.

Trastuzumab-resistant breast cancer cells-derived tumor xenograft models exhibit distinct sensitivity to lapatinib treatment in vivo

BackgroundResistance to HER2-targeted therapies, including the monoclonal antibody trastuzumab and tyrosine kinase inhibitor lapatinib, frequently occurs and currently represents a significant clinical challenge in the management of HER2-positive breast cancer. We previously showed that the trastuzumab-resistant SKBR3-pool2 and BT474-HR20 sublines were refractory to lapatinib in vitro as compared to the parental SKBR3 and BT474 cells, respectively. The in vivo efficacy of lapatinib against trastuzumab-resistant breast cancer remained unclear.ResultsIn tumor xenograft models, both SKBR3-pool2- and BT474-HR20-derived tumors retained their resistance phenotype to trastuzumab; however, those tumors responded differently to the treatment with lapatinib. While lapatinib markedly suppressed growth of SKBR3-pool2-derived tumors, it slightly attenuated BT474-HR20 tumor growth. Immunohistochemistry analyses revealed that lapatinib neither affected the expression of HER3, nor altered the levels of phosphorylated HER3 and FOXO3a in vivo. Interestingly, lapatinib treatment significantly increased the levels of phosphorylated Akt and upregulated the expression of insulin receptor substrate-1 (IRS1) in the tumors-derived from BT474-HR20, but not SKBR3-pool2 cells. ConclusionsOur data indicated that SKBR3-pool2-derived tumors were highly sensitive to lapatinib treatment, whereas BT474-HR20 tumors exhibited resistance to lapatinib. It seemed that the inefficacy of lapatinib against BT474-HR20 tumors in vivo was attributed to lapatinib-induced upregulation of IRS1 and activation of Akt. Thus, the tumor xenograft models-derived from SKBR3-pool2 and BT474-HR20 cells serve as an excellent in vivo system to test the efficacy of other HER2-targeted therapies and novel agents to overcome trastuzumab resistance against HER2-positive breast cancer.

Do statins enhance the antitumor effect of trastuzumab emtansine (T-DM1)?: Real-life cohort.

Human epidermal growth factor receptor 2 (HER2)-targeting therapies have become crucial in the management of HER2-positive breast cancer. Trastuzumab emtansine (T-DM1) is a microtubule inhibitor and HER2-targeted antibody conjugate. T-DM1 resistance is most likely influenced by factors involved in the biological mechanisms of T-DM1 action. This study aimed to examine the efficacy of statins, which influence HER-2-based therapies via the caveolin-1 (CAV-1) protein, in female breast cancer patients receiving T-DM1. Our study included 105 patients with HER2-positive metastatic breast cancer treated with T-DM1. The progression-free survival (PFS) and overall survival (OS) of patients who received statins concurrently with T-DM1 versus those who did not were compared. During the median 39.5 (95% confidence interval [CI]: 35.6-43.5) months of follow-up, 16 (15.2%) patients received statins, and 89 (84.8%) patients did not. Median OS was significantly higher in patients using statins than in patients not using statins (58.8 vs 26.5 months, P = .016). The association between statin use and PFS did not reach statistical significance (34.7 vs 9.9 months, P = .159). Multivariate Cox regression analysis showed that better performance status (hormone receptor [HR]: 0.30, 95% CI: 0.13-0.71, P = .006), use of trastuzumab plus pertuzumab prior to T-DM1 (HR: 0.37, 95% CI: 0.18-0.76, P = .007) and use of statins with T-DM1 (HR: 0.29, 95% CI: 0.12-0.70, P = .006) were independent factors that prolong OS duration. Our study showed that T-DM1 is more effective at treating HER2-positive breast cancer in people who receive statins concurrently with T-DM1 than those who do not.

Flashback Foreword: Anti-HER2 Monoclonal Antibody as a Single Agent

Article Tools FLASHBACK FOREWORD Article Tools OPTIONS & TOOLS Export Citation Track Citation Add To Favorites Rights & Permissions COMPANION ARTICLES Multinational Study of the Efficacy and Safety of Humanized Anti-HER2 Monoclonal Antibody in Women Who Have HER2-Overexpressing Metastatic Breast Cancer That Has Progressed After Chemotherapy for Metastatic Disease. February 28, 2023 ARTICLE CITATION DOI: 10.1200/JCO.22.02679 Journal of Clinical Oncology - published online before print March 7, 2023 PMID: 36881997 Flashback Foreword: Anti-HER2 Monoclonal Antibody as a Single Agent Pamela J. Goodwin , MD, MSc1,2xPamela J. GoodwinSearch for articles by this author Show More 1Department of Medicine, Sinai Health System, University of Toronto, Toronto, Ontario, Canada2Former Associate Editor, Journal of Clinical Oncology, Alexandria, VA https://doi.org/10.1200/JCO.22.02679 First Page Full Text PDF Figures and Tables © 2023 by American Society of Clinical OncologyTHE TAKEAWAYIn 1999, Cobleigh et al1 demonstrated important activity of a single-agent recombinant humanized monoclonal antibody (now known as trastuzumab) targeting the human epidermal growth factor receptor (HER2) in women with pretreated metastatic HER2-positive breast cancer. This, along with subsequent studies of trastuzumab and other agents targeting HER2 in the metastatic and (neo)adjuvant settings, has revolutionized the management of HER2-positive breast cancer, leading to dramatic improvements in outcomes in both the early and metastatic settings.AUTHOR'S DISCLOSURES OF POTENTIAL CONFLICTS OF INTERESTFlashback Foreword: Anti-HER2 Monoclonal Antibody as a Single AgentThe following represents disclosure information provided by the author of this manuscript. All relationships are considered compensated unless otherwise noted. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/jco/authors/author-center.Open Payments is a public database containing information reported by companies about payments made to US-licensed physicians (Open Payments).Pamela J. GoodwinResearch Funding: Epic Sciences (Inst)No other potential conflicts of interest were reported. Companion Multinational Study of the Efficacy and Safety of Humanized Anti-HER2 Monoclonal Antibody in Women Who Have HER2-Overexpressing Metastatic Breast Cancer That Has Progressed After Chemotherapy for Metastatic Disease

Unveiling the Potential of Liquid Biopsy in HER2-Positive Breast Cancer Management.

Simple SummaryBreast cancer (BC) is the most prevailing cancer in women worldwide. Amongst the different BC subtypes, human epidermal growth factor receptor 2 (HER2)-positive tumours are characterised by an overexpression of the HER2 membrane receptor. Nowadays, HER2-status assessment relies on immunohistochemical methodologies in the tumour tissue, which could be complemented by novel methodologies to improve the clinical management of these patients. In this regard, liquid biopsy is an easy, rapid, and minimally invasive tool to obtain circulating tumour components from body fluids. Herein, by reviewing the published studies, we aim to decipher the clinical validity of liquid biopsy in both early and metastatic HER2-positive BC.Invasive breast cancer (BC) is the most common cancer in women with a slightly increasing yearly incidence. BC immunohistochemical characterisation is a crucial tool to define the intrinsic nature of each tumour and personalise BC patients’ clinical management. In this regard, the characterisation of human epidermal growth factor receptor 2 (HER2) status guides physicians to treat with therapies tailored to this membrane receptor. Standardly, a tumour solid biopsy is therefore required, which is an invasive procedure and has difficulties to provide the complete molecular picture of the tumour. To complement these standard-of-care approaches, liquid biopsy is a validated methodology to obtain circulating tumour components such as circulating tumour DNA (ctDNA) and circulating tumour cells (CTCs) from body fluids in an easy-to-perform minimal-invasive manner. However, its clinical validity in cancer is still to be demonstrated. This review focusses on the utilisation of both ctDNA and CTCs in early and metastatic HER2-positive BC tumours. We discuss recently published studies deciphering the capacity of liquid biopsy to determine the response to neoadjuvant and adjuvant therapies as well as to predict patients’ outcomes.

Not all small HER2 positive breast cancers have the same clinical outcome in the North-East of Scotland

HER2-positive breast cancers, representing up to 20% of all breast cancers, are more aggressive and have poorer outcomes. Systemic therapy has been proven to prevent disease recurrence and improve survival. Existing literature provides only limited evidence to support this in smaller HER2-positive tumors. The study aimed to evaluate HER-2 positive breast cancer management and treatment of all T1N0 tumors in the North of Scotland, diagnosed 2012–2019. Clinical-pathological details, comorbidities, treatments and clinical events were retrieved from the Scottish North Cancer Alliance audit database and analyzed using univariate and multivariate analysis including cox-regression and log-rank testing (SPSSv23).Overall, 299 patients (41% screen detected/ 56.9% symptomatic /2.1% other), median age 63 years and median tumor size 13 mm, were included. Most cancers were grade 2/3 (43.1%/ 55.5%). Most patients (59.5%) received treatment with trastuzumab (tT); 40.8% concurrent with chemotherapy and endocrine therapy. 7.7% of patients received neo adjuvant chemotherapy. Median follow-up time was 2.6 years, with recurrence on average occurring 2.9 years after diagnosis. Patients receiving trastuzumab were younger, had a higher grade and larger size tumor. 78.5% of patients in the untreated group (non-tT) were ER positive compared to 65.2% in the treated group (tT). Trastuzumab significantly lowered breast cancer recurrence (Tt=3.4% versus non-Tt=8.3%, p = 0.022 HR= 0.096, 95% CI 0.025–0.361). In conclusion, receiving anti-HER2 treatment significantly improved clinical outcome in this T1N0 patient group. Consideration, at the very least informed discussions with patients, should be undertaken to treat these early stage HER2-positive breast cancers.

Brain Metastases in HER2-Positive Breast Cancer: Current and Novel Treatment Strategies.

Simple SummaryDevelopment of brain metastases is an important event for patients with breast cancer, and it affects both their survival and their quality of life. Patients with HER2-positive breast cancer are more commonly affected by brain metastases compared to patients with HER2-negative/hormone receptor-positive breast cancer. It is essential to find proper therapies that reduce the risk for metastasis in the brain, as well as agents that are active when metastatic lesions develop. Management of HER2-positive breast cancer has drastically improved in recent years due to the development of several drugs targeting the HER2 receptor. This review aims to provide insight into current and novel treatment strategies for patients with brain metastases from HER2-positive breast cancer.Development of brain metastases can occur in up to 30–50% of patients with breast cancer, representing a significant impact on an individual patient in terms of survival and quality of life. Patients with HER2-positive breast cancer have an increased risk of developing brain metastases; however, screening for brain metastases is not currently recommended due to the lack of robust evidence to support survival benefit. In recent years, several novel anti-HER2 agents have led to significant improvements in the outcomes of HER2-positive metastatic breast cancer. Despite these advances, brain and leptomeningeal metastases from HER2-positive breast cancer remain a significant cause of morbidity and mortality, and their optimal management remains an unmet need. This review presents an update on the current and novel treatment strategies for patients with brain metastases from HER2-positive breast cancer and discusses the open questions in the field.

The global landscape of availability, accessibility and affordability of essential diagnostics and therapeutics for the management of HER2-positive breast cancer: The ONCOLLEGE-001 survey

Aim of the StudyBarriers in access to essential care are key determinants of disparities in cancer survival. Breast cancer (BC) is the most common cancer and lead cause of mortality among women, 60 % occurring in low- and middle-income countries (LMs). A quarter of BC are characterized by an over-expression of the epidermal growth factor receptor 2 (HER2). Valuable strategies to diagnose and manage patients with HER2-positive BC have been determined and some considered essential health interventions. ONCOLLEGE-001 is a global survey of availability, accessibility, and affordability of essential HER2 diagnostics and therapeutics. MethodA self-administered questionnaire was shared electronically to oncologists, identified from oncology networks. Data were analyzed using descriptive statistics, per income areas and geographic regions. ResultsWe received 191 responses (84 % response rate). The majority of the responders were from LMs (n = 153) and were physician providers. Immunohistochemistry was the most common HER2 diagnostics available (n = 185). A third of the responders from low/lower-middle and a half of upper-middle income countries had HER2 testing only in the private sector. Trastuzumab was not available for 8 %: when available, 15%–21% reported accessibility only as out-of-pocket expenditure; when not reimbursed, only 10 % of the providers could significantly offer this intervention. Availability of trastuzumab biosimilars was reported in more than a half of the responders (n = 107). ConclusionStark disparities are reported, with high out-of-pocket expenses for HER2 testing and significant financial barriers to access trastuzumab treatments. Policy solutions are urgently warranted for the selection, prioritization, and reimbursement of essential health interventions, to result in improved population health. Policy summary statementthe inclusion of essential services for cancer management should be assured and financed in the benefit packages of healthcare to all. Prioritizing high-value health interventions, including medicines and medical devices, is critical to deliver impactful programs on population health.

Annular atrophic lichen planus induced by anti‐HER2 antibodies

Pertuzumab and trastuzumab are monoclonal antibody inhibitors targeting human epidermal growth factor receptor 2 (HER-2) and are increasingly being utilised in the management of HER2-positive breast cancer, having been demonstrated to improve progression-free survival in conjunction with docetaxel. We present a rare presentation of a lichenoid drug eruption, in an annular atrophic variant, in a 35-year-old woman after initiation of HER2-inhibitor (pertuzumab and trastuzumab) therapy for metastatic breast cancer.

Evolving standards of care and new challenges in the management of HER2-positive breast cancer.

The management of human epidermal growth factor receptor (HER2)-positive breast cancer (BC) has rapidly evolved over the last 20 years. Major advances have led to US Food and Drug Administration approval of 7 HER2-targeted therapies for the treatment of early-stage and/or advanced-stage disease. Although oncologic outcomes continue to improve, most patients with advanced HER2-positive BC ultimately die of their disease because of primary or acquired resistance to therapy, and patients with HER2-positive early BC who have residual invasive disease after preoperative systemic therapy are at a higher risk of distant recurrence and death. The concept of treatment de-escalation and escalation is increasingly important to optimally tailor therapy for patients with HER2-positive BC and is a major focus of the current review. Research efforts in this regard are discussed as well as updates regarding the evolving standard of care in the (neo)adjuvant and metastatic settings, including the use of novel combination therapies. The authors also briefly discuss ongoing challenges in the management of HER2-positive BC (eg, intrinsic vs acquired drug resistance, the identification of predictive biomarkers, the integration of imaging techniques to guide clinical practice), and the treatment of HER2-positive brain metastases. Research aimed at superseding these challenges will be imperative to ensure continued progress in the management of HER2-positive BC going forward.

A Mini-review on HER2 Positive Breast Cancer and its Metastasis: Resistance and Treatment Strategies

HER2 positive breast cancer is an aggressive breast cancer followed by brain metastasis, which emerges at the later stage of breast cancer or after a few years of treatment. HER2+ breast cancer brain metastasis is a complex fatal disease with short survival and resistance to first-line drugs such as Trastuzumab, lapatinib, etc. The resistance can be due to the upregulation/downregulation of various proteins of downstream pathways mainly PI3K/AKT pathway and MAPK pathway. In addition, the Blood-brain Barrier (BBB) and Blood Tumor Barrier (BTB) also hinder the delivery to brain metastases. Thus controlling the altered proteins of the downstream pathway can be a targeted approach to control breast cancer and its brain metastasis. At the same time, targeted delivery to metastatic sites can give a synergistic effect in controlling brain metastasis and increasing the survival period. Various type of targeted nanocarriers such as single, dual, or multitargeted, pH specific, or stimuli sensitive nanocarriers can be employed for providing specific delivery to HER2+ cancer cells. Furthermore, combinations such as Trastuzumab with tyrosine kinase inhibitors (lapatinib, neratinib, afatinib), chemotherapeutic drugs (paclitaxel, doxorubicin, capecitabine), or some natural compounds (curcumin, Lycorine, berberine) with anti-apoptotic activity can provide an additional effect in the management of HER2 positive breast cancer and its metastasis.

Integrating trastuzumab biosimilars and HER2-directed therapies into HER2-positive breast cancer management.

The approval of the humanized monoclonal antibody trastuzumab in 1998 changed the trajectory of treatment and subsequent outcomes for patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer and is now the standard of care in the neoadjuvant, adjuvant, and metastatic settings. However, as with most biologic drugs, trastuzumab comes with a relatively high price tag compared with traditional cytotoxic chemotherapy and contributes to healthcare budgets. Three engineered products related to trastuzumab-2 antibody-drug conjugates, ado-trastuzumab emtansine and fam-trastuzumab deruxtecan-nxki, as well as the subcutaneous trastuzumab/hyaluronidase-have since been approved and have expanded the treatment options for this patient population. The approval of 5 trastuzumab biosimilars as of the end of 2019 holds the promise of considerable cost savings, but challenges to integrating their use into patient care must be addressed. Barriers to their use, including physician uncertainty to switch patients from the reference drug to the therapeutic biosimilar and patients' lack of understanding about biosimilars, are common in the United States. It is also important that all stakeholders, including managed care professionals, pharmacists, and practice administrators, understand how to incorporate trastuzumab biosimilars into formulary discussions, clinical care plans and processes, and educational initiatives for healthcare providers and patients.

Immunotherapy for HER2-Positive Breast Cancer: Changing the Paradigm

To summarize and discuss the available evidence and ongoing efforts in order to establish the efficacy and safety of immunotherapeutic approaches in HER2-positive breast cancer. The introduction into the clinic of anti-HER2–targeted therapies more than 15 years ago resulted in a substantial improvement in the outcome of patients with HER2-overexpressing breast cancer. However, only patients with the highest levels of HER2 expression will potentially benefit from these therapies and, unfortunately, many patients progress or relapse after optimal treatment. As metastatic breast cancer remains an incurable disease, new therapeutic strategies are urgently needed to improve clinical outcomes in these patients. Immunotherapy is emerging as a new treatment modality in breast cancer. Although it has long been regarded as a non-immunogenic disease, new preclinical and clinical studies have emphasized the therapeutic potential of the use of anti-HER2 therapies in combination with immune checkpoint inhibitors in improving outcomes in breast cancer patients. Emerging results from clinical trials evaluating immunotherapeutic agents, either as monotherapy or in combination with anti-HER2–targeted therapies, are showing promising results in the management of HER2-positive breast cancer.

Overcoming trastuzumab resistance in HER2-positive breast cancer using combination therapy.

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC) comprises around 20-30% of all BC subtypes and is correlated with poor prognosis. For many years, trastuzumab, a monoclonal antibody, has been used to inhibit the HER2 activity. Though, the main resistance to trastuzumab has challenged the use of this drug in the management of HER2-positive BC. Therefore, the determination of resistance mechanisms and the incorporation of new agents may lead to the development of a better blockade of the HER family receptor signaling. During the last few years, some therapeutic drugs have been developed for treating patients with trastuzumab-resistant HER2-positive BC that have more effective influences in the management of this condition. In this regard, the present study aimed at reviewing the mechanisms of trastuzumab resistance and the innovative therapies that have been investigated in trastuzumab-resistant HER2-positive BC subjects.

Abstract P6-16-08: Using continuing professional development (CPD) as an investigative tool to improve clinical practice and interdisciplinary team treatment

Abstract Background: Continued and rapid evolution of diagnosis and staging methods along with the development of new treatments has changed the decision-making process for cancer patients into a more complex task. In breast cancer, quality measures related to sentinel lymph node biopsy (SLNB), axillary dissection (AD), HER2 testing and use of HER2-targeted therapy, provide parameters for assessing care quality. We assessed the influence of quality improvement education (QIE) on alignment with BC quality indicators. Methods: 39 members of the interprofessional team at Inova (an integrated care network of 5 hospitals) participated in the QIE components. For a baseline Inova provided deidentified electronic medical records (EMR) data that included a total of 67 breast cancer patients treated between 12/1/16 – 2/28/17. The patients diagnosed with HER2+ breast cancer records were retrospectively reviewed for adherence to quality measures pertaining to HER2 testing, SLNB, AD, and treatment. Follow-up reviews were completed 6 months after the launch of the online component, which included 142 patients. Results: Patient and disease characteristics were generally similar across the 2 cohorts. At baseline, treatment selection for patients with advanced stage cancer was consistent. The original goal of the activity was to assess adherence to quality measures in breast cancer treatment, in our assessment stage the team discovered potential undersampling of sentinel lymph nodes in patients who underwent neoadjuvant chemotherapy for clinically node-positive, with 3 of 8 patients (37.5%) having only 1 or 2 lymph nodes sampled. The educational programming improved recognition of the risk of false negative rates of sampling under 2 lymph nodes in this setting. In addition, the Inova team recommended that the triage protocol be changed to include the medical oncologist earlier in the treatment decision making process in tandem with the surgeon. In the post-program patient data, 26 patients with clinically N1/N2 disease had neoadjuvant therapy and a SLN biopsy. Of these, 3 (11.5%) had only 1 lymph node sampled, suggesting an increased adherence to recommended sampling. The educational program also improved participant knowledge of the phase III APHINITY trial efficacy findings, which was consistent with an increase in the use of pertuzumab-containing adjuvant therapy for early breast cancer (use of TCHP, 0% vs 46% in the pre-program and post-program charts, respectively). In addition, participants in the educational programming increased awareness of the need for reflex testing in the event of an equivocal HER2 IHC result. In the post-program follow-up, no cases of equivocal HER2 IHC staining lacked reflex testing with FISH. Taken together, these findings are consistent with practice change following interventional medical education for incorporating best practices and emerging clinical data in the management of HER2-positive breast cancer. Citation Format: Harnden K, Hester D. Using continuing professional development (CPD) as an investigative tool to improve clinical practice and interdisciplinary team treatment [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 P6-16-08.

A prospective study to assess the clinical utility of serum HER2 extracellular domain in breast cancer with HER2 overexpression.

PurposeWe explored the clinical utility of human epidermal growth factor receptor-2 extracellular domain (HER2/ECD) in patients treated for an invasive breast cancer with HER2 overexpression.MethodsWe prospectively studied HER2/ECD levels in the sera of 334 women included between 2007 and 2014, all treated with trastuzumab. HER2/ECD levels were measured at diagnosis, during treatments, and along the follow-up. We investigated the relationship of HER2/ECD with other clinicopathological parameters at diagnosis, its prognosis value, and its utility during the monitoring of a neoadjuvant treatment and the follow-up.ResultsElevated HER2/ECD at diagnosis correlated positively with parameters associated with tumor aggressiveness. Disease-free survival of non-metastatic patients was significantly shorter in patients with high HER2/ECD at diagnosis (HR = 13.6, 95 % CI 1.6–113.6, P < 0.0001). Progression-free survival of metastatic patients was better for patients with low HER2/ECD (HR = 2.6, 95 % CI 1.2–5.3, P = 0.033). A multivariate analysis revealed that HER2/ECD level at diagnosis was an independent prognosis factor. During neoadjuvant therapy, a significant decrease in HER2/ECD was reported only for the complete histological response group (P = 0.031). During the follow-up, HER2/ECD helped predict relapse, disease progression, and metastases before imaging in 18.6 % cases of the studied cohort.ConclusionsHER2/ECD is a prognosis factor that is valuable in evaluating the neoadjuvant treatment efficiency. HER2/ECD also appears to be a helpful surveillance biomarker for the early diagnosis of relapses and to predict the fate of metastases. This study brings evidences to support the use of HER2/ECD in the management of HER2-positive breast cancer.

Downregulation of LncRNA GAS5 causes trastuzumab resistance in breast cancer.

Therapeutic resistance to trastuzumab caused by dysregulation of long noncoding RNAs (lncRNAs) is a major obstacle to clinical management of HER2-positive breast cancer. To investigate which lncRNAs contribute to trastuzumab resistance, we screened a microarray of lncRNAs involved in the malignant phenotype of trastuzumab-resistant SKBR-3/Tr cells. Expression of the lncRNA GAS5 was decreased in SKBR-3/Tr cells and in breast cancer tissue from trastuzumab-treated patients. Inhibition of GAS5 promoted SKBR-3 cell proliferation, and GAS5 knockdown partially reversed lapatinib-induced inhibition of SKBR-3/Tr cell proliferation. GAS5 suppresses cancer proliferation by acting as a molecular sponge for miR-21, leading to the de-repression of phosphatase and tensin homologs (PTEN), the endogenous target of miR-21. Moreover, mTOR activation associated with reduced GAS5 expression was required to suppress PTEN. This work identifies GAS5 as a novel prognostic marker and candidate drug target for HER2-positive breast cancer.

Abstract P5-09-01: Simulation in continuing professional development in oncologic care: Advancing evidence-based decisions in the management of HER2-positive metastatic breast cancer

Abstract Background: Breast cancer is the second leading cause of cancer death among women. The growth factor receptor HER2 is overexpressed in 20% to 30% of invasive breast cancers, and use of HER2-targeted therapies have improved responses and survival in patients with metastatic breast cancer (MBC). However, the choice of the most appropriate agents and their sequencing is crucial to maximizing beneficial patient outcomes. A study was conducted to determine if simulation-based educational interventions to address underlying clinical practice gaps could improve competence and performance of oncologists in the management of HER2-positive breast cancer. Methods: A cohort of US-practicing oncologists who participated in online simulation-based education was evaluated. The interventions consisted of two cases presented in a platform that allowed physician learners to assess the patient and choose from an extensive database of diagnostic possibilities matching the scope and depth of actual practice. Clinical decisions made by participants were analyzed using a sophisticated decision engine, and instantaneous clinical guidance was provided at each decision point employing current evidence-based and expert faculty recommendations. Participant decisions were collected after clinical guidance and compared with each user's baseline data using a 2-tailed paired T-test to provide P values for assessing the impact of simulation-based education on the clinical decisions made by participants as of 12/4/2014. Results: The assessment sample consisted of 123 oncologists who made clinical decisions within the simulation and proceeded to the concluding debrief section. As a result of clinical guidance provided through simulation, significant improvements were observed in several areas of management of patients with HER2-positive MBC, specifically: •35% improvement (P&amp;lt;.001) in the selection of the preferred treatment regimen (trastuzumab, pertuzumab, with a taxel) in the first-line setting •21% improvement (P=.003) in evidence-based treatment selection for individuals whose disease progressed on first-line therapy •A 35% decrease was seen in the number of participants who selected trastuzumab for individuals whose disease progressed on first-line therapy, which demonstrated an improvement in oncologists ability to select the most appropriate selection based on the current evidence-base •39% (P&amp;lt;.001) improvement in the number of oncologists who ordered adverse event counseling for the patient •Similarly, 33% more participants (P&amp;lt;.001) referred a patient for psychosocial counseling after clinical guidance The data gathered during simulation also provided insights into the remaining gaps, including the choice of the most appropriate, evidence-based first line HER2-targeted regimen in patients with MBC. Conclusion: This study showed improvements in evidence-based practice patterns of oncologists who were selecting therapeutic protocols for patients with HER2-positive MBC, thus demonstrating that simulation-based instruction can result in an increase in evidence-based clinical decisions and, therefore, may play a role in improving the quality of care and patient outcomes. Citation Format: Herrmann TL, Blevins D, Warters M, Peters P. Simulation in continuing professional development in oncologic care: Advancing evidence-based decisions in the management of HER2-positive metastatic breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-09-01.