Factor Receptor 2-positive Breast Cancer Research Articles

Impact of Dose Intensity on Pathologic Complete Response Rate in HER2-Positive Breast Cancer Patients Receiving Neoadjuvant Docetaxel, Carboplatin, Trastuzumab and Pertuzumab (TCHP).

Neoadjuvant chemotherapy is the cornerstone treatment for locally advanced breast cancer. Balancing toxicity and efficacy are a common concern of patients treated with chemotherapy. The objective of this study was to determine the impact of dose intensity on pathologic complete response (pCR) at the time of surgery in patients with human epidermal growth factor receptor 2-positive (HER2+) breast cancer. A retrospective, single-center review was conducted on patients with HER2+ breast cancer who received neoadjuvant docetaxel, carboplatin, trastuzumab and pertuzumab (TCHP) followed by definitive surgery. A total of 159 patients were included in the analysis; pCR was obtained in 66 patients (42%). There was no statistically significant difference between the mean dose intensity of each of the individual agents in TCHP and pCR rates. The mean overall dose intensity of docetaxel, carboplatin, trastuzumab and pertuzumab was 90.5%, 90.9%, 97.5%, and 93.9%, respectively. Although higher chemotherapy dose intensity (>85%) was associated with higher pCR rates, no statistically significant difference was found compared with chemotherapy dose intensity <85%. The TCHP regimen was difficult to tolerate; 104 patients (65%) required a dose reduction or dose delay during treatment due to toxicity. The TCHP regimen, which combines chemotherapy and HER2-directed therapy is effective at obtaining pCR in patients with locally advanced HER2+ breast cancer. These results suggest that the dose intensity of the individual agents did not have a significant impact on pCR rates. Given these findings, providers may be more comfortable allowing dose reductions for greater patient tolerability without sacrificing efficacy.

Abstract P5-13-31: Pik3ca mutations and myc amplification are associated with pathological complete response in human epidermal growth factor receptor 2-positive breast cancer patients receiving pyrotinib combined with trastuzumab neoadjuvant treatment

Abstract Background: Our previous study reported a good efficacy and safety of pyrotinib combined with trastuzumab neoadjuvant treatment in human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients. We further explored the potential biomarkers for the efficacy of pyrotinib combined with trastuzumab neoadjuvant treatment in HER2-positive breast cancer patients. Methods:To date, a total of 162 patients with early-stage breast cancer were enrolled for the neoadjuvant pyrotinib combined with trastuzumab treatment clinical trial (ChiCTR1900022293). By the method of 425 genes next-generation sequencing (NGS), the genomic characteristics of them were evaluated for the potential correlation with postoperative pathological complete response (pCR). Results:. Among the cohort of 162 cases, a total of 43 patients have completed the whole therapy as well as final surgery and acquired qualified sequencing analysis report, and 25 of them achieved total pCR. The most frequently mutated driver genes were TP53 (80%), PIK3CA (46%), ERBB2 (10%), NF1 (8%), NBN (8%), ATRX (8%), respectively. In terms of somatic copy number alterations, the most frequent alterations are gain or amplification of ERBB2 (66%), MYC (24%), CKD12 (14%), CCND1 (12%) and ZNF217 (12%), respectively. The median tumor mutation burden (TMB) was 4.76 mut/Mb (0.00-29.61). Compared with pCR populations, non-pCR populations had higher median TMB but not statistically significant (5.29 vs 3.85 mut/Mb, P=0.141). In addition, the pCR rate of patients with wild-type PIK3CA is significantly higher than that of patients with mutated PIK3CA (80.0% vs 27.8%, P = 0.001), and those with amplified MYC are more likely to achieve pCR (22.2% vs 67.6%, P = 0.023). Conclusions:Preliminary results suggested that HER2-positive breast cancer patients with activating mutations in PIK3CA and amplified MYC are less likely to benefit from pyrotinib combined with trastuzumab neoadjuvant therapy, which need larger sample size to validate. Citation Format: Qiyun Shi, Juncheng Xuhong, Jia Ge, Feng Liu, Yang Lan, Yi Zhang, Luo Tao, Xiuwu BIan, Xiaowei Qi, Jun Jiang. Pik3ca mutations and myc amplification are associated with pathological complete response in human epidermal growth factor receptor 2-positive breast cancer patients receiving pyrotinib combined with trastuzumab neoadjuvant treatment [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-31.

Abstract OT2-26-01: Open-label, multinational, multicenter, phase 3b/4 study of trastuzumab deruxtecan (T-DXd) in patients with or without baseline brain metastasis with previously treated advanced/metastatic human epidermal growth factor receptor 2-positive breast cancer (HER2+ BC): DESTINY-Breast12

Abstract Background: HER2+ BC is associated with a high incidence (up to 50%) of brain metastasis (BM) despite advances in treatment (Zimmer AS et al. Cancer Rep (Hoboken). 2020;e1274; Hurvitz SA et al. Clin Cancer Res. 2019;25:2433-2441). Although several agents have been studied in patients (pts) with HER2+ BC with BM, an unmet medical need remains due to the poor prognosis in this pt population. In DESTINY-Breast01, T-DXd demonstrated efficacy in the overall population and preliminary efficacy in a pt subgroup with stable BM, with a confirmed objective response rate (ORR) of 61.4% and an extracranial confirmed ORR by independent central review (ICR) of 58.3%, respectively, median progression-free survival (PFS) of 19.4 and 18.1 mo, respectively, and median duration of response (DOR) of 20.8 and 16.9 mo, respectively (Modi S et al. Cancer Res. 2021. Abst PD3-06; Jerusalem G et al. Ann Oncol. 2020. Abst 138O). Here we describe a trial evaluating T-DXd in pts ± BM with previously treated advanced/metastatic HER2+ BC. Trial design: DESTINY-Breast12 (NCT04739761) is an open-label, multicenter, international (86 sites in the US, Europe, Australia, and Japan), phase 3b/4 study assessing the efficacy and safety of T-DXd 5.4 mg/kg q3w in pts with HER2+ BC ± BM. Pts will be enrolled in 1 of 2 cohorts (250 pts each): cohort 1 (−BM at baseline) and cohort 2 (+BM at baseline). Pts must have previously treated advanced/metastatic HER2+ BC that has progressed with ≥1 prior anti-HER2-based regimen and received ≤2 lines of therapy in the metastatic setting (excludes pts with prior tucatinib). Pts with BM must have untreated BM not needing immediate local therapy or previously treated stable or progressing BM. Primary endpoints are ORR in cohort 1 and PFS in cohort 2 (both by RECIST version 1.1 per ICR). Secondary endpoints in both cohorts are OS, DOR, time to progression, duration of subsequent therapy, PFS2, safety, and changes in symptoms, functioning, and QOL. Incidence of new symptomatic CNS metastasis (CNSM) is a secondary endpoint in cohort 1, and ORR and CNS ORR by RECIST 1.1 per ICR, CNS PFS and DOR, and time to new CNSM are secondary endpoints in cohort 2. Citation Format: Nancy U Lin, Eva Ciruelos, Guy Jerusalem, Volkmar Müller, Naoki Niikura, Giuseppe Viale, Emma Oscroft, Shawn Anand, Graham Walker, Nadia Harbeck. Open-label, multinational, multicenter, phase 3b/4 study of trastuzumab deruxtecan (T-DXd) in patients with or without baseline brain metastasis with previously treated advanced/metastatic human epidermal growth factor receptor 2-positive breast cancer (HER2+ BC): DESTINY-Breast12 [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT2-26-01.

Abstract OT1-14-02: Phase 3 study of trastuzumab deruxtecan (T-DXd) with or without pertuzumab vs a taxane, trastuzumab and pertuzumab in first-line (1L), human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (mBC): DESTINY-Breast09

Abstract Background: A combination of a taxane, trastuzumab, and pertuzumab (THP) is the standard-of-care (SOC) 1L treatment for patients (pts) with HER2+ mBC; THP demonstrated median progression-free survival (mPFS) of 18.7 mo and overall survival (OS) of 56.5 mo (Swain et al. N Engl J Med. 2015;372:724-734). However, pts eventually develop resistance to treatment. Novel treatment options are necessary in order to delay the emergence of resistance and provide better clinical outcomes, improve quality of life (QOL), and prolong survival in the 1L setting. T-DXd has demonstrated efficacy in pts with heavily pretreated HER2+ mBC, with an objective response rate (ORR) of 61.4%, duration of response (DOR) of 20.8 mo, and mPFS of 19.4 mo (Modi et al. Cancer Res. 2021. Abstract PD3-06). Data from DESTINY-Breast01 supported global approvals of T-DXd in HER2+ mBC. Here we describe a phase 3 trial evaluating the efficacy and safety of T-DXd ± pertuzumab compared with THP in the 1L treatment of HER2+ mBC. Trial design: DESTINY-Breast09 (NCT04784715) is a global, multicenter, randomized, phase 3 trial assessing the efficacy and safety of T-DXd with or without pertuzumab compared with SOC THP as 1L treatment in pts with HER2+ (IHC 3+ or ISH+ assessed locally per ASCO-CAP guidelines and centrally confirmed) advanced or mBC. This study consists of 3 treatment arms: arm A (T-DXd + placebo), arm B (T-DXd + pertuzumab), and arm C (THP). Randomization is 1:1:1 and pts will be stratified by prior treatment status (de novo vs recurrent), hormone receptor status (positive vs negative), and PIK3CA mutation status (detected vs not detected). Pts (N≈1134) must have had no prior chemotherapy or HER2-targeted therapy for advanced or mBC (1 prior line of endocrine therapy is allowed for mBC). The primary endpoint is PFS by blinded independent central review. Secondary endpoints include PFS by investigator assessment, OS, ORR, DOR, PFS2, health-related quality of life (QOL), pharmacokinetics, immunogenicity, and safety. Citation Format: Sara M Tolaney, Romualdo Barroso-Sousa, Zefei Jiang, Yeon Hee Park, Mothaffar Rimawi, Cristina Saura, Andreas Schneeweiss, Masakazu Toi, Tinghui Yu, Jagdish Shetty, Pia Herbolsheimer, Sibylle Loibl. Phase 3 study of trastuzumab deruxtecan (T-DXd) with or without pertuzumab vs a taxane, trastuzumab and pertuzumab in first-line (1L), human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (mBC): DESTINY-Breast09 [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT1-14-02.

Abstract P2-13-35: Pyrotinib combined with fulvestrant in women with hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer: A single-arm phase II clinical trial

Abstract Background: HR+/HER2+ breast cancer is a unique molecular subtype of HER2+ breast cancer, which is characterized by mild biological behavior and is sensitive to endocrine therapy. Although the standard treatment for HR+/HER2+ metastatic breast cancer is chemotherapy combined with anti-HER2 therapy, this combination is not ideal for patients because of the heavy side effects of chemotherapy. Previous studies have shown that endocrine therapy combined with anti-HER2 therapy can also bring survival benefits to these patients. However, due to the limitations of previous treatment, the optimal combination mode of endocrine and anti-HER2 therapies has not been found. Pyrotinib is the most efficient pan-HER tyrosine kinase inhibitor (TKI) with irreversible blocking of HER2, while fulvestrant is the most potent estrogen receptor (ER) inhibitor. Previous cell experiments showed the cross-talk between ER and HER2 receptor pathways, indicating that the two signal pathways were important mechanisms of drug resistance for each other. Further research showed that ER inhibitor fulvestrant had synergistic effect with HER2 inhibitor pyrotinib. Therefore, we firstly explored the efficacy and safety of pyrotinib combined with fulvestrant in the treatment of HR+/HER2+ metastatic breast cancer.Methods: Eligible patients had histologically confirmed HR+/HER2+ metastatic breast cancer with no more than one line of prior treatment for metastatic disease. Those with central nervous system metastases or any prior HER2 TKI were excluded. Patients were treated with oral pyrotinib 400 mg once daily plus intramuscular injection of fulvestrant 500 mg on days 1, 15, and 29, and once every 28 days thereafter. The primary endpoint was progression-free survival (PFS), as assessed by the data and safety monitoring committee. Secondary endpoints included objective response rate, disease control rate (DCR), overall survival and safety. We also explored the efficacy of subgroups defined by different gene signatures, which were identified using comprehensive genomic variation profiling (FoundationOne CDx). This study is registered with ClinicalTrials.gov, NCT04034589.Results: From July 9, 2019 to June 20, 2021, 34 patients were enrolled; 19 (55.8%) patients had visceral metastases. Of 14 patients with measurable disease according to RECIST 1.1, seven (50%) achieved objective response. The DCR was 84.6%. Nine of the 34 included patients discontinued treatment because of disease progression, and PFS was immature. Twelve patients had available data of comprehensive genomic variation profiling, and the results showed that six patients had PIK3CA mutation, ten had TP53 mutation, and 11 had ErbB2 overexpression. The most common treatment-related adverse events were diarrhea and fatigue. The incidence of grade 3 or greater diarrhea was 12.1% (4/33) in patients with available safety data. No patient discontinued treatment because of adverse events. Conclusions: The combination of pyrotinib and fulvestrant was convenient and effective with manageable toxicity, which may offer a chemotherapy-free alternative treatment option for patients with HR+/HER2+ metastatic breast cancer. Citation Format: Ying Wang, Jianli Zhao, Zhongyu Yuan, Guorong Zou, Haiyan Li, Linxiaoxiao Ding, Yaping Yang, Jie Chai, Donggeng Liu, Herui Yao. Pyrotinib combined with fulvestrant in women with hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer: A single-arm phase II clinical trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-13-35.

Abstract P4-05-02: Impact of hormone receptor status on clinicopathological characteristics and outcomes among HER2-positive metastatic breast cancer patients in the ESME database

Abstract Introduction. Evidence suggests that human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (MBC) patients have different clinical characteristics and outcomes according to the hormone receptor (HR) status. We aimed to evaluate the impact of HR status in this population extracted from a large real-world database. Methods. We performed a retrospective analysis of HER2+ MBC patients (pts) included in the real world ESME MBC database (NCT03275311) between 2008 and 2017. Descriptive statistics, the Kaplan-Meier method and Cox proportional hazards models were used to report characteristics, outcomes and prognostic factors. Results. Of 4,145 HER2+ MBC pts eligible for our analysis, 1,449 (35%) had HR-negative (HR-), while 2,696 (65%) had HR-positive (HR+) tumors. Pts with HR- tumors had metastases earlier (median 9.3 vs 28.0 mo from primary cancer), had more often de novo MBC (47.6% vs 38.1%), grade III tumors (50.9% vs 33.6%), visceral metastases (70.9% vs 60.8%) and less often bone only disease (8.4% vs 21.1%) compared to those with HR+ tumors, all p&amp;lt;0.001. Pts with HR+ MBC received less frequently an anti-HER2+ targeted therapy during first line of treatment than pts with HR- tumors (74.9% vs 90.8%, p&amp;lt;0.001). Pts with HR- MBC had significantly worse outcomes than those with HER2+/HR+ MBC, with median overall survival (OS) 42.0 mo [95% CI 38.8-45.2] vs 55.9 mo [95% CI 53.7-59.4], p&amp;lt;0.001, and median progression-free survival (PFS) 9.8 mo [95%CI 9.2-11] vs 12.2 mo [95%CI 11.5-12.9], p=0.012, respectively. The independent prognostic value of HR status was confirmed in a multivariable analysis for OS (HR- versus HR+, hazard ratio=1.25 [1.13-1.39], p&amp;lt;0.001) but not for PFS (hazard ratio=1.03 [95%CI 0.95-1.13], p=0.8) (Table 1 for OS). The multivariable analysis also included tumor grade, age at and time to MBC diagnosis, presence of visceral metastases, number of metastatic sites and performance status as prognostic factors. In the HR+ population, ER and PR statuses were not prognostic. Conclusions. These data confirm the remaining strong and independent adverse prognostic effect of negative hormone receptors among pts with HER2+ MBC treated in the past 12 years. Cox multivariable model for overall survival in patients with HER2-positive MBCCategoriesNHazard ratio95% CIp valueTumor gradeGrade I/II17711&amp;lt;0.001Grade III15741.13[1.03-1.25]NA5811.15[1.01-1.31]ER/PR statusER+/PR+14571&amp;lt;0.001ER+/PR-9711.03[0.92-1.16]ER-/PR+1021.03[0.77-1.36]ER-/PR-13961.25[1.13-1.39]Age at MBC diagnosis&amp;lt;55 years17561&amp;lt;0.001≥55 years21701.26[1.16-1.38]Time to MBC diagnosis&amp;lt;6 months16351&amp;lt;0.0016-24 months5082.53[2.22-2.89]24-60 months8721.75[1.56-1.96]≥60 months9111.19[1.06-1.35]Visceral metastasesNo14061&amp;lt;0.001Yes25201.54[1.38-1.71]No of metastatic sites&amp;lt;330911&amp;lt;0.001≥38351.65[1.48-1.84]ECOG PSPS 010101&amp;lt;0.001PS 18021.62[1.4-1.87]PS 2-43923.34[2.83-3.95]NA17222.34[2.07-2.64] Citation Format: Luc Cabel, Matthieu Carton, Veronique Dieras, Thierry Petit, Severine Guiu, Corinne Veyret, Anthony Goncalves, Lionel Uwer, Paule Augereau, Jean-Marc Ferrero, Christelle Levy, Florence Dalenc, Isabelle Desmoulins, Marie Ange Mouret-Reynier, Marc Debled, Thomas Bachelot, Jean-Christophe Eymard, Barbara Pistilli, Jean Sebastien Frenel, Michael Chevrot, Audrey Mailliez, Marcela Carausu. Impact of hormone receptor status on clinicopathological characteristics and outcomes among HER2-positive metastatic breast cancer patients in the ESME database [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-05-02.

The TILs-US score on ultrasonography can predict the pathological response to neoadjuvant chemotherapy for human epidermal growth factor receptor 2-positive and triple-negative breast cancer

BackgroundThe tumor-infiltrating lymphocyte (TIL)-ultrasonography (US) score determined through characteristic US findings has predictive performance of lymphocyte-predominant breast cancer (LPBC). This study aimed to investigate whether the TIL-US score before neoadjuvant chemotherapy (NAC) can predict the pathological complete response (pCR). MethodsWe evaluated patients with human epidermal growth factor receptor type 2 (HER2)-positive breast cancer (n = 55) and triple-negative breast cancer (TNBC) (n = 24) who underwent surgery after NAC from November 2012 to April 2019. Pre-NAC biopsy examination was performed to examine stromal TILs; the cutoff value for predicting pCR was defined as ≥50% stromal TILs. The TILs-US score was calculated from the pre-NAC US findings. Based on previous data, the cutoff value for predicting pCR was set at ≥4 points. ResultsForty-six patients achieved pCR. The TIL-US score was significantly associated with the pCR rate (p = 0.003) but not the pre-NAC biopsy findings (p = 0.055). Multivariate logistic regression analysis revealed that a TILs-US score ≥4 and HER2 positivity were significant pCR predictors (odds ratio [OR] 3.69; p = 0.031; OR 8.74; p = 0.025). ConclusionsTILs-US scores can be used to evaluate the therapeutic effect of NAC, and may be used as a non-invasive, convenient, and an alternative method to assess stromal TILs in pre-treatment biopsies.

Sociodemographic and Clinical Predictors of Neoadjuvant Chemotherapy in cT1-T2/N0 HER2-Amplified Breast Cancer

The optimal treatment strategy for small node-negative human epidermal growth factor receptor 2-positive (HER2+) breast cancer remains controversial. Neoadjuvant chemotherapy may risk overtreatment, whereas surgery first fails to identify patients with residual disease in need of escalated adjuvant systemic therapy. We investigated patient characteristics associated with receipt of neoadjuvant chemotherapy. Adult women with cT1-T2/N0, HER2+ breast cancer between 2013 and 2017 in the National Cancer Database who underwent surgery within 8 months of diagnosis were included. Patients were classified as receiving neoadjuvant chemotherapy versus a surgery-first approach. We assessed the sociodemographic and clinical predictors of neoadjuvant chemotherapy versus surgery first and associations between neoadjuvant chemotherapy and breast cancer treatments using multivariable regression models. We identified 56,784 women, of whom 12,758 (22%) received neoadjuvant chemotherapy, 29,139 (53%) received adjuvant chemotherapy, 12,907 (24%) received no chemotherapy, and 1980 were missing chemotherapy information. After adjustment, cT2 stage was the strongest predictor of neoadjuvant chemotherapy compared with surgery first. Younger age and later diagnosis year were positively associated with receipt of neoadjuvant chemotherapy. In contrast, hormone receptor positivity, Black race, rural county, and government-funded or no health insurance were inversely associated with neoadjuvant chemotherapy. In multivariable analyses, patients who received neoadjuvant chemotherapy were more likely to have a mastectomy (vs. lumpectomy) and sentinel lymph node biopsy or no nodal surgery (vs. axillary lymph node dissection). Patients who received neoadjuvant chemotherapy were more likely to receive multi-agent (vs. single-agent) chemotherapy than those who received adjuvant chemotherapy. Substantial differences in the utilization of neoadjuvant chemotherapy exist in women with HER2+ breast cancer, which reflect both clinical parameters and disparities. Optimal treatment strategies should be implemented equitably across sociodemographic groups.

FTY720 in resistant human epidermal growth factor receptor 2-positive breast cancer

The prognosis of patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer has considerably improved. However, no reliable treatment besides anti-HER2 strategies has been available. FTY720, a small-molecule compound used for treating refractory multiple sclerosis, has been reported to have beneficial effects against cancers. We therefore evaluated the efficacy of FTY720 in trastuzumab-resistant breast cancer cells and investigated the possible mechanism involved. This study evaluated morphological changes after FTY720 treatment. Antiproliferative WST-1 assays and LDH Cytotoxicity Assay Kits were used to determine the treatment effects of drugs, whereas Western blot analysis was used to evaluate protein expression. Apoptotic events were investigated through annexin V staining and TUNEL assays using flow cytometry. FTY720 was effective in trastuzumab-resistant breast cancer cell lines despite the presence of PIK3CA mutation. Studied on a xenograft mouse model, FTY720-treated groups had statistically significantly poorer HCC1954 xenograft growth in vivo compared with the control group. Our findings suggest that FTY720 can overcome resistance to trastuzumab therapy in patients with HER2-positive breast cancer, with FTY720 plus trastuzumab might offer even better efficacy in vitro and in vivo.

Systemic Treatments for Metastatic Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: Old Certainties and New Frontiers

Epidermal growth factor receptor 2 (EGFR2, also known as HER2) overexpression and/or amplification confers a more aggressive clinical behavior but also represents a therapeutic opportunity for targeted therapies in breast cancer (BC). Over the last 2 decades, the prognosis of HER2-positive metastatic BC patients has improved due to the introduction of anti-HER2 agents including trastuzumab and novel, emerging drugs and combinations such as trastuzumab deruxtecan and tucatinib – trastuzumab - capecitabine. Herein, we provide a critical overview of current clinical recommendations and emerging treatment options for metastatic HER2-positive BC, especially focusing on recently presented and published clinical trials in this setting.

Retrospective Analysis of Preferred Hepatectomy Combined with Systemic Drug Therapy for Breast Cancer Liver Metastases

To understand the efficacy and safety of preferred hepatectomy combined with postoperative systemic drug therapy for breast cancer liver metastases is the objective of the study. We retrospectively analyzed 3 patients with liver metastases included in the initial metastatic sites after breast cancer surgery that preferred hepatectomy and postoperative systemic drug therapy in our department between October 2016 and November 2019, combined with literature review to share our experience. All patients were estrogen receptor and/or human epidermal growth factor receptor-2 positive with good performance status and no obvious drug resistance but still had some unfavorable factors. Patient 1 was 73 y old; patient 2 developed 8 liver metastases after only 7 mo after breast surgery and patient 3 had the largest (6.3 cm) liver metastatic lesion and simultaneous extra-hepatic lymph nodes metastases. They all underwent radical (R0) resection of hepatectomy without complications, combined with systemic drug therapy including timely postoperative chemotherapy, sequential targeted therapy and endocrine therapy. During 28-64 mo of follow-up, they all have eventually achieved clinically complete remission of tumor in the whole body with good quality of life. The longest progression-free survival has been above 64 mo. Preferred hepatectomy combined with postoperative systemic drug therapy was safe and may benefit for estrogen receptor and/or human epidermal growth factor receptor-2 positive breast cancer patients with liver included in the initial metastatic sites who had good performance status, no drug resistance, potential R0 resection, limited and controllable extrahepatic metastasis.

Long-Term Safety and Effectiveness of PF-05280014 (a Trastuzumab Biosimilar) Treatment in Patients with HER2-Positive Metastatic Breast Cancer: Updated Results of a Randomized, Double-Blind Study.

BackgroundPF-05280014 was compared with trastuzumab sourced from the European Union (trastuzumab-EU), each plus paclitaxel, as first-line treatment for human epidermal growth factor receptor 2-positive metastatic breast cancer in a phase III study. Equivalence between treatment groups was demonstrated.ObjectiveThe aim of this study was to report long-term safety and overall survival (OS) over 6 years after the first patient was screened.Patients and methodsRandomized patients received intravenous PF-05280014 or trastuzumab-EU, each plus paclitaxel, until objective disease progression. OS, long-term safety, subgroup safety (patients ongoing after day 378), and time-to-treatment discontinuation (TTD) were assessed based on the final statistical analysis plan amended for the ad-hoc analyses.ResultsOf 707 randomized patients (n = 352, PF-05280014; n = 355, trastuzumab-EU), 252 (71.6%) in the PF-05280014 and 251 (70.7%) in the trastuzumab-EU group discontinued treatment due to objective progression. Overall, 451 (63.8%) patients completed the study. Between groups (PF-05280014; trastuzumab-EU), estimated median TTDs were 12.25 and 12.06 months (p = 0.692); 61 (17.3%) and 67 (18.9%) patients died; stratified hazard ratio for OS was 0.929 (95% confidence interval 0.656–1.316; p = 0.339); estimated survival rates were 82.3 and 77.4% at 2 years and 77.2 and 75.3% at 3 years. The incidences of treatment-emergent adverse events (TEAEs) overall (98.6%; 96.6%) and for grades ≥3 (41.0%; 43.1%) were comparable between groups. In patients (n = 265; n = 264) ongoing after day 378, the incidences of any TEAEs, grade ≥3 TEAEs, and serious TEAEs were comparable between the treatment groups.ConclusionLong-term safety and OS were consistent with previous results and demonstrated no clinically meaningful differences between treatment groups.Trial registrationClinicalTrials.gov: NCT01989676 (21 November 2013); and EudraCT: 2013-001352-34 (18 December 2013).Supplementary InformationThe online version contains supplementary material available at 10.1007/s40259-021-00513-7.

CT Findings From Interstitial Lung Diseases in Patients With Metastatic Breast Cancer Treated With Fam-Trastuzumab Deruxtecan: A Single Institutional Experience.

This single-institute, retrospective cohort study enrolled patients with human epidermal growth factor receptor 2-positive metastatic breast cancer treated with trastuzumab deruxtecan between August 2017 and January 2021 from four previous studies. Of 31 patients, 4 (12.9%) had interstitial lung disease (ILD). The dominant pattern observed on computed tomography was organizing pneumonia (100%), comprising subpleural consolidations in the lung periphery. However, no dominant distribution was observed in radiological lesions of the lungs. Of all the tested patients, lower lobe predominance was noted in 2 (50.0%) patients, upper lobe predominance in 1 (25.0%) patient, and diffused lobe distribution in 1 (25.0%) patient. All events were confined to the Common Terminology Criteria for Adverse Events grade 1 or 2 (100%). None of the patients died. Despite the small number of cases investigated, the incidence of trastuzumab deruxtecan-induced ILD in the Korean population was comparable to that previously reported.

Neoadjuvant pyrotinib plus trastuzumab and nab-paclitaxel for HER2-positive early or locally advanced breast cancer: an exploratory phase II trial.

The anti-tumor activity and acceptable tolerability of pyrotinib plus chemotherapy have been demonstrated in phase III trials in human epidermal growth factor receptor 2-positive metastatic breast cancer (BC). In this study, we assessed the efficacy and safety of neoadjuvant pyrotinib plus trastuzumab and albumin-bound paclitaxel in women with human epidermal growth factor receptor 2-positive early or locally advanced BC. In this single-arm exploratory phase II trial, patients with untreated human epidermal growth factor receptor 2-positive BC (stage IIA-IIIC) received pyrotinib 400 mg once daily, trastuzumab 4 mg/kg loading dose, followed by 2 mg/kg once a week, and albumin-bound paclitaxel 125 mg/m2 once a week for four 21-day cycles before surgery. The primary endpoint of the study was total pathological complete response (pCR) rate, defined as no microscopic invasive tumor remnants in the breast and axillary lymph nodes. The secondary endpoints were investigator-assessed objective response rate (ORR) and adverse event profiles. Between May 17, 2019 and November 26, 2019, a total of 21 patients were enrolled. The total pCR rate was 57.1% (12/21), whereas 23.8% (5/21) and 19.0% (4/21) of patients had minimal and moderate residual disease (RD), respectively. The ORR reached 100% (21/21) at the end of the neoadjuvant therapy. Grade ≥3 treatment-related adverse events were observed in 42.9% (9/21) of patients, including decreased neutrophil count [7 (33.3%)], diarrhoea [6 (28.6%)], decreased white blood cell count [5 (23.8%)], and vomiting [2 (9.5%)]. Adverse event-related dose reduction and interruption of pyrotinib occurred in 6 (28.6%) and 11 (52.4%) patients, respectively. In women with human epidermal growth factor receptor 2-positive early or locally advanced BC, neoadjuvant pyrotinib plus trastuzumab and albumin-bound paclitaxel effectively promoted total pCR rate with an acceptable safety profile (ClinicalTrials.gov, NCT04152057).

Prognostic value of tumor mutation burden and the relationship between tumor mutation burden and immune infiltration in HER2+ breast cancer: a gene expression-based study.

Whether tumor mutation burden (TMB) correlated with improved survival outcomes or promotion of immunotherapies remained controversy in various malignancies. We aimed to explore the prognostic value of TMB and the relationship between TMB and immune infiltration in human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC). We downloaded somatic mutation data and clinical information for 216 HER2+ BC patients from the The Cancer Genome Atlas (TCGA) and cBioPortal databases. Patients were divided into high- and low-TMB groups through TMB calculation. Cox regression analysis was used to establish an immune- and mutant-related risk model based on 5-hub genes. The relationship between 5-hub genes mutants and the level of immune infiltration, as well as the relationship between the risk model and the immune microenvironment were analyzed by "TIMER" database. TMB was negatively correlated with overall survival (OS) and disease-free survival (DFS), and high TMB may inhibit immune infiltration in HER2+ BC. Furthermore, risk score classified effectively patients into low- and high-risk groups in training and validation cohorts. The infiltration of CD4+ T cells and NK cells and the levels of immune checkpoint pathway genes were lower in the high-risk group, which indicated a poor prognosis. Higher TMB correlated with poor survival outcomes and might inhibit the immune infiltrates in HER2+ BC. The 5-hub TMB-related signature conferred lower immune cells infiltration which deserved further validation.

Updates on targeting human epidermal growth factor receptor 2-positive breast cancer: what's to know in 2021.

To highlight recent practice changing clinical trials, focusing on those leading to new drug approvals, in human epidermal growth factor receptor 2-positive (HER2+) breast cancer. The improved disease-free survival of adjuvant trastuzumab emtansine (T-DM1) over trastuzumab in patients with residual disease has made neoadjuvant sequencing of therapy standard for most patients with early stage disease. In patients with metastatic HER2+ breast cancer, trastuzumab deruxtecan has recently shown dramatically improved efficacy over T-DM1. Tucatinib is an oral tyrosine kinase inhibitor with best in class blood-brain barrier penetration. Margetuximab, a novel HER2-targeted chimeric monoclonal antibody with an engineered Fc receptor designed to activate local immune response, was recently approved in heavily pretreated patients based on modest but significant improvement in progression-free survival. Patients with HER2+ breast cancer have a variety of therapeutic options in the early stage and metastatic setting. Optimal sequencing of therapy will depend on patient-specific factors such as site of tumor progression and underlying comorbidities. De-escalation of the first-line metastatic regimen may be considered in select patients with hormone positive/HER2+ breast cancer, by using endocrine therapy instead of chemotherapy in combination with HER2-targeted therapy, which may improve side effects without sacrificing efficacy.

Changes in epicardial adipose tissue among women treated with trastuzumab for breast cancer

BackgroundEpicardial adipose tissue (EAT) as an endocrine organ, secreting hormones, and inflammatory cytokines is associated with adverse cardiovascular outcomes and may have a role in trastuzumab-induced cardiotoxicity (TIC). We sought to assess changes in EAT volume and radiodensity after receiving trastuzumab and if they are associated with TIC. MethodsA total of 185 women treated with trastuzumab for human epidermal growth factor receptor 2-positive breast cancer were retrospectively recruited. All patients underwent echocardiography and CT before and during trastuzumab therapy. The time interval between CT and echocardiography was <10 days. EAT volume and density were quantified by CT. TIC was defined as a left ventricular ejection fraction (LVEF) decrease of >10% and < 53%. ResultsOf the 185 patients, 18 (9.7%) experienced TIC. After receiving trastuzumab, EAT volume and radiodensity were increased, despite similar BMI. TIC group showed a significantly higher increment of EAT volume (21.2 ± 6.3 vs. 11.7 ± 10.5 ml, p < 0.001) and radiodensity (2.7 ± 1.8 vs. 1.5 ± 2.0HU, p < 0.05) than no TIC group. There was a high negative correlation between changes in EAT volume and LVEF (r = −0.70; p < 0.001) and a moderately negative correlation between changes in EAT radiodensity and LVEF (r = −0.50; p < 0.001). Increased EAT volume, but not radiodensity appeared to be a good imaging biomarker for TIC (AUC: 0.79 vs. 0.65, p < 0.05). ConclusionsEAT volume and radiodensity were increased after receiving trastuzumab particularly in the TIC patients despite similar BMI. Notably, the increased EAT volume rather than radiodensity was strongly negatively associated with LVEF and appeared to be a good imaging biomarker of TIC.

Management of Diarrhea in Patients with HER2-Positive Breast Cancer Treated with Neratinib: A Case Series and Summary of the Literature

IntroductionNeratinib and neratinib-based combinations have demonstrated efficacy for treatment of human epidermal growth factor receptor 2–positive (HER2+) early-stage and metastatic breast cancers. However, diarrhea has been reported as a common adverse event leading to neratinib discontinuation. Results from the CONTROL trial suggest that proactive diarrhea management with antidiarrheal prophylaxis or dose escalation of neratinib from a lower starting dose to the full FDA-approved dose of 240 mg/day can reduce the incidence, duration, and severity of neratinib-associated diarrhea in patients with early-stage breast cancer. Dose escalation has been included in the FDA-approved label for both early-stage and metastatic HER2+ breast cancer since June 2021.Case seriesThis series of five cases details real-world clinical implementation of strategies for management of neratinib-induced diarrhea in patients with early-stage and metastatic HER2+ breast cancer, including a patient with a pre-existing gastrointestinal disorder.Management and outcomeIn four of five cases, diarrhea was managed with neratinib dose escalation, and antidiarrheal prophylaxis with loperamide plus colestipol was used in the remaining case. Management of diarrhea allowed all patients to remain on therapy.DiscussionThis case series shows that neratinib-associated diarrhea can be managed effectively with neratinib dose escalation from a lower initial starting dose and/or prophylactic antidiarrheal medications in a real-world clinical setting. The findings highlight the importance of patient-provider communication in proactive management of adverse events. Widespread implementation of the strategies described here may improve adherence and thereby clinical outcomes for patients with HER2+ breast cancer treated with neratinib.

Combination of Carriers with Complementary Intratumoral Microdistributions of Delivered α-Particles May Realize the Promise for 225Ac in Large, Solid Tumors.

α-particle radiotherapy has already been shown to be impervious to most resistance mechanisms. However, in established (i.e., large, vascularized) soft-tissue lesions, the diffusion-limited penetration depths of radiolabeled antibodies or nanocarriers (≤50-80 μm) combined with the short range of α-particles (4-5 cell diameters) may result in only partial tumor irradiation, potentially limiting treatment efficacy. To address this challenge, we combined carriers with complementary intratumoral microdistributions of the delivered α-particles. We used the α-particle generator 225Ac, and we combined a tumor-responsive liposome (which, on tumor uptake, releases into the interstitium a highly diffusing form of its radioactive payload [225Ac-DOTA], potentially penetrating the deeper parts of tumors where antibodies do not reach) with a separately administered, less-penetrating radiolabeled antibody (irradiating the tumor perivascular regions where liposome contents clear too quickly). Methods: In a murine model with orthotopic human epidermal growth factor receptor 2-positive BT474 breast cancer xenografts, the biodistributions of each carrier were evaluated, and the control of tumor growth was monitored after administration of the same total radioactivity of 225Ac delivered by the 225Ac-DOTA-encapsulating liposomes, by the 225Ac-DOTA-SCN--labeled trastuzumab, and by both carriers at equally split radioactivities. Results: Tumor growth was significantly more inhibited when the same total injected radioactivity was divided between the 2 separate carriers than when delivered by either of the carriers alone. The combined carriers enabled more uniform intratumoral microdistributions of α-particles, at a tumor dose that was lower than the dose delivered by the antibody alone. Conclusion: This strategy demonstrates that more uniform microdistributions of the delivered α-particles within established solid tumors improve efficacy even at lower tumor doses. Augmentation of antibody-targeted α-particle therapies with tumor-responsive liposomes may address partial tumor irradiation, improving therapeutic effects.

TAMI-05. FATTY ACID SYNTHESIS IS REQUIRED FOR HER2+ BREAST CANCER BRAIN METASTASIS

Abstract Brain metastases are refractory to therapies that control systemic disease in patients with human epidermal growth factor receptor 2-positive breast cancer and the brain microenvironment contributes to this therapy resistance. Nutrient availability can vary across tissues, therefore metabolic adaptations required for brain metastatic breast cancer growth may introduce liabilities that can be exploited for therapy. Here we assessed how metabolism differs between breast tumors in brain versus extracranial sites and found that fatty acid synthesis is elevated in breast tumors growing in the brain. We determine that this phenotype is an adaptation to decreased lipid availability in the brain relative to other tissues, resulting in site-specific dependency on fatty acid synthesis for breast tumors growing at this site. Genetic or pharmacological inhibition of fatty acid synthase reduces human epidermal growth factor receptor 2-positive breast tumor growth in the brain, demonstrating that differences in nutrient availability across metastatic sites can result in targetable metabolic dependencies.