A multicenter randomized phase II study of sequential epirubicin/cyclophosphamide followed by docetaxel with or without celecoxib or trastuzumab according to HER2 status, as primary chemotherapy for localized invasive breast cancer patients

Harnessing the synergistic potential of NK1R antagonists and selective COX-2 inhibitors for simultaneous targeting of TNBC cells and cancer stem cells

Triple-negative breast cancer (TNBC) lacks the expression of oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), rendering it unresponsive to endocrine therapy and HER2 targeted treatments. Though certain chemotherapeutics targeting the cell cycle have shown efficacy to a certain extent, the presence of chemotherapy-resistant cancer stem cells (CSCs) presents a significant challenge in tackling TNBC. Multiple lines of evidence suggest the upregulation of neuropeptide Substance P (SP), its NK-1 receptor (NK1R) and the Cyclooxygenase-2 (COX-2) enzyme in TNBC patients. Upregulation of the SP/NK1R system and COX-2 influences major signalling pathways involved in cell proliferation, growth, survival, angiogenesis, inflammation, metastasis and stem cell activity. The simultaneous activation and crosstalk between the pathways activated by SP/NK1R and COX-2 consequently increase the levels of key regulators of self-renewal pathways in CSCs, promoting stemness. The combination therapy with NK1R antagonists and COX-2 inhibitors can simultaneously target TNBC cells and CSCs, thereby enhancing treatment efficacy and reducing the risk of recurrence and relapse. This review discusses the rationale for combining NK1R antagonists and COX-2 inhibitors for the better management of TNBC and a novel strategy to deliver drug cargo precisely to the tumour site to address the challenges associated with off-target binding.

Neoadjuvant anthracycline-based (5-FEC) or anthracycline-free (docetaxel/carboplatin) chemotherapy plus trastuzumab and pertuzmab in HER2 + BC patients according to their TOP2A: a multicentre, open-label, non-randomized phase II trial

PURPOSE

Previous studies have reported the benefit of dual HER2-targeting combined to neoadjuvant chemotherapy in HER2-amplified breast cancer (HER2 + BC). Moreover, besides the cardiac toxicity following their association to Trastuzumab, anthracyclines chemotherapy may not profit all patients. The NeoTOP study was designed to evaluate the complementary action of Trastuzumab and Pertuzumab, and the relevance of an anthracycline-based regimen according to TOP2A amplification status.

METHODS

Open-label, multicentre, phase II study. Eligible patients were aged ≥ 18 with untreated, operable, histologically confirmed HER2 + BC. After centralized review of TOP2A status, TOP2A-amplified (TOP2A+) patients received FEC100 for 3 cycles then 3 cycles of Trastuzumab (8 mg/kg then 6 mg/kg), Pertuzumab (840 mg/kg then 420 mg/kg), and Docetaxel (75mg/m2 then 100mg/m2). TOP2A-not amplified (TOP2A-) patients received 6 cycles of Docetaxel (75mg/m2) and Carboplatin (target AUC 6 mg/ml/min) plus Trastuzumab and Pertuzumab. Primary endpoint was pathological Complete Response (pCR) using Chevallier's classification. Secondary endpoints included pCR (Sataloff), Progression-Free Survival (PFS), Overall Survival (OS), and toxicity.

RESULTS

Out of 74 patients, 41 and 33 were allocated to the TOP2A + and TOP2A- groups respectively. pCR rates (Chevallier) were 74.4% (95%CI: 58.9-85.4) vs. 71.9% (95%CI: 54.6-84.4) in the TOP2A + vs. TOP2A- groups. pCR rates (Sataloff), 5-year PFS and OS were 70.6% (95%CI: 53.8-83.2) vs. 61.5% (95%CI: 42.5-77.6), 82.4% (95%CI: 62.2-93.6) vs. 100% (95%CI: 74.1-100), and 90% (95%CI: 69.8-98.3) vs. 100% (95%CI: 74.1-100). Toxicity profile was consistent with previous reports.

CONCLUSION

Our results showed high pCR rates with Trastuzumab and Pertuzumab associated to chemotherapy. They were similar in TOP2A + and TOP2A- groups and the current role of neoadjuvant anthracycline-based chemotherapy remains questioned.

TRIAL REGISTRATION NUMBER

NCT02339532 (registered on 14/12/14).

Racial and Ethnic Disparities in European Breast Cancer Clinical Trials

Breast cancer is the most prevalent female cancer worldwide with known correlations between the race and tumor characteristics of the patients and prognosis. International and US-based studies, however, have reported a disproportionate representation of Black and Hispanic patients in clinical trials. This is the first study assessing race and ethnicity reporting trends and inclusion in European breast cancer trials. The PubMed and ClinicalTrials.gov databases were systematically searched for trials on breast cancer treatment conducted exclusively in Europe between 2010 and 2022. Of the 97 identified trials, race was reported in 10.31%. Multinational participation, but not the study size or trial phase, was significantly associated with higher race reporting trends. These 10 trials featured a White-predominant population, with 1.08% Asian and 0.88% Black patients included. The acquisition of the race and ethnicity data of patients in European trials is lower compared to the U.S. or worldwide studies and does not permit extensive analysis of minority participation. In a limited analysis, the low rates of minority participation are concerning, based on population-based data on minorities in select European countries. These observations should encourage race reporting practices in European breast cancer trials and adequate minority participation to support the generalizability of the results of the studies and promote healthcare equity.

An inflamed tumor cell subpopulation promotes chemotherapy resistance in triple negative breast cancer

Individual cancers are composed of heterogeneous tumor cells with distinct phenotypes and genotypes, with triple negative breast cancers (TNBC) demonstrating the most heterogeneity among breast cancer types. Variability in transcriptional phenotypes could meaningfully limit the efficacy of monotherapies and fuel drug resistance, although to an unknown extent. To determine if transcriptional differences between tumor cells lead to differential drug responses we performed single cell RNA-seq on cell line and PDX models of breast cancer revealing cell subpopulations in states associated with resistance to standard-of-care therapies. We found that TNBC models contained a subpopulation in an inflamed cellular state, often also present in human breast cancer samples. Inflamed cells display evidence of heightened cGAS/STING signaling which we demonstrate is sufficient to cause tumor cell resistance to chemotherapy. Accordingly, inflamed cells were enriched in human tumors taken after neoadjuvant chemotherapy and associated with early recurrence, highlighting the potential for diverse tumor cell states to promote drug resistance.

Differential response of HER2-positive breast cancer to anti-HER2 therapy based on HER2 protein expression level

BACKGROUND

Increasing data indicate that HER2-positive (HER2 + ) breast cancer (BC) subtypes exhibit differential responses to targeted anti-HER2 therapy. This study aims to investigate these differences and the potential underlying molecular mechanisms.

METHODS

A large cohort of BC patients (n = 7390) was utilised. The clinicopathological characteristics and differential gene expression (DGE) of HER2+ immunohistochemical (IHC) subtypes, specifically HER2 IHC 3+ and IHC 2 + /Amplified, were assessed and correlated with pathological complete response (pCR) and survival in the neoadjuvant and adjuvant settings, respectively. The role of oestrogen receptor (ER) status was also investigated.

RESULTS

Compared to HER2 IHC 3+ tumours, BC patients with IHC 2 + /Amplified showed a significantly lower pCR rate (22% versus 57%, P < 0.001), shorter survival regardless of HER2 gene copy number, were less classified as HER2 enriched, and enriched for trastuzumab resistance and ER signalling pathway genes. ER positivity significantly decreased response to anti-HER2 therapy in IHC 2 + /Amplified, but not in IHC 3 + BC patients.

CONCLUSION

In HER2 + BC, overexpression of HER2 protein is the driver of the oncogenic pathway, and it is the main predictor of response to anti-HER2 therapy. ER signalling pathways are more dominant in BC with equivocal HER2 expression. personalised anti-HER2 therapy based on IHC classes should be considered.

Landscape of neoadjuvant therapy in HER2-positive breast cancer: a systematic review and network meta-analysis

BACKGROUND

The recommended preoperative approach for HER2-positive breast cancer is unclear. We aimed to investigate the following: i) what is the optimal neoadjuvant regimen and ii) whether anthracyclines could be excluded.

METHODS

A systematic literature search in Medline, Embase and Web of Science databases was performed. Studies had to satisfy the following criteria: i) randomised controlled trials (RCTs), ii) enroled patients treated preoperatively for HER2-positive BC (breast cancer), iii) at least one treatment group received an anti-HER2 agent, iv) available information of any efficacy end-point and v) published in English. A network meta-analysis with a frequentist framework using random-effects model was used to pool direct and indirect evidence. Pathologic complete response (pCR), event-free survival (EFS) and overall survival (OS) were the efficacy end-points of interest, and selected safety end-points were also analysed.

RESULTS

A total of 11,049 patients with HER2-positive BC (46 RCTs) were included in the network meta-analysis, and 32 different regimens were evaluated. Dual anti-HER2-therapy, with pertuzumab or tyrosine kinase inhibitors, combined with chemotherapy was significantly superior to trastuzumab and chemotherapy in terms of pCR, EFS and OS. However, a higher risk of cardiotoxicity was observed with dual anti-HER2-therapy. Anthracycline-based chemotherapy was not associated with better efficacy outcomes in comparison with non-anthracycline-based chemotherapy. In anthracycline-free regimens, the addition of carboplatin presented numerically better efficacy outcomes.

CONCLUSION

Dual HER2 blockade with chemotherapy is the recommended choice as neoadjuvant therapy for HER2-positive breast cancer, preferably by omitting anthracyclines in favour of carboplatin.

The adverse effects of trastuzumab-containing regimes as a therapy in breast cancer: A piggy-back systematic review and meta-analysis

BACKGROUND

Trastuzumab is a valuable therapy option for women with ERBB2(HER2)+ breast cancer tumours, often used in combination with chemotherapy and alongside other therapies. It is known to have adverse effects, but these have proved difficult to separate from the effects of other concurrent therapies patients are usually taking. This study aims to assess the adverse effects specifically attributable to trastuzumab, and whether they vary by patient subgroup or concurrent therapies.

METHODS

As registered on PROSPERO (CRD42019146541), we used previous systematic reviews as well as the clinicaltrials.gov registry to identify randomised controlled trials in breast cancer which compared treatment regimes with and without trastuzumab. Neoadjuvant, adjuvant and metastatic settings were examined. Data was extracted from those which had, as of July 2022, reported adverse events. Risk of bias was assessed using ROB2. Primary outcomes were adverse events of any type or severity (excluding death). A standard random-effects meta-analysis was performed for each outcome independently. In order to ascertain whether adverse effects differed by individual factors such as age or tumour characteristics, or by use of trastuzumab concurrently with hormone therapy, we examined individual-level patient data for one large trial, HERA.

RESULTS

79 relevant trials were found, of which 20 contained comparable arms of trastuzumab-containing therapy and corresponding matched therapy without trastuzumab. This allowed a comparison of 8669 patients receiving trastuzumab versus 9556 receiving no trastuzumab, which gave a list of 25 statistically and clinically significant adverse effects related to trastuzumab alone: unspecified pain, asthenia, nasopharyngitis, skin disorders (mainly rash), dyspepsia, paraesthesia, infections (often respiratory), increased lacrimation, diarrhoea, myalgia, oedema (limb/peripheral), fever, nose bleeds, cardiac events, insomnia, cough, back pain, dyspnoea, chills, dizziness or vertigo, hypertension, congestive heart failure, increased levels of aspartate aminotransferase, gastrointestinal issues and dehydration. Analysis of individual patient-level data from 5102 patients suggested that nausea is slightly more likely for women taking trastuzumab who are ER+ /also taking hormone therapy than for those who are ER-/not taking hormone therapy; no other potential treatment-subgroup interactions were detected. We found no evidence for significantly increased rates of neutropenia, anaemia or lymphopenia in patients on trastuzumab-containing regimes compared to those on comparable regimes without trastuzumab.

CONCLUSIONS

This meta-analysis should allow clinicians and patients to better identify and quantify the potential adverse effects of adding trastuzumab to their treatment regime for breast cancer, and hence inform their decision-making. However, limitations include serious risk of bias due to heterogeneity in reporting of the outcomes and the open-label nature of the trials.

The Efficacy and Safety of Celecoxib in Addition to Standard Cancer Therapy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The purpose of this meta-analysis was to evaluate the efficacy and safety of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, in addition to standard anticancer therapy. Randomized controlled trials (RCTs) that evaluated the efficacy and safety of celecoxib-combined cancer therapy were systematically searched in PubMed and Embase databases. The endpoints were overall survival (OS), progression-free survival (PFS), disease-free survival (DFS), objective response rate (ORR), disease control rate (DCR), pathological complete response (pCR), and adverse events (AEs). The results of 30 RCTs containing 9655 patients showed limited benefits in celecoxib-combined cancer therapy. However, celecoxib-combined palliative therapy prolonged PFS in epidermal growth factor receptor (EGFR) wild-type patients (HR = 0.57, 95%CI = 0.35–0.94). Moreover, despite a slight increase in thrombocytopenia (RR = 1.35, 95%CI = 1.08–1.69), there was no increase in other toxicities. Celecoxib combined with adjuvant therapy indicated a better OS (HR = 0.850, 95%CI = 0.725–0.996). Furthermore, celecoxib plus neoadjuvant therapy improved the ORR in standard cancer therapy, especially neoadjuvant therapy (overall: RR = 1.13, 95%CI = 1.03–1.23; neoadjuvant therapy: RR = 1.25, 95%CI = 1.09–1.44), but not pCR. Our study indicated that adding celecoxib to palliative therapy prolongs the PFS of EGFR wild-type patients, with good safety profiles. Celecoxib combined with adjuvant therapy prolongs OS, and celecoxib plus neoadjuvant therapy improves the ORR. Thus, celecoxib-combined cancer therapy may be a promising therapy strategy.

Neoadjuvant Treatment with HER2-Targeted Therapies in HER2-Positive Breast Cancer: A Systematic Review and Network Meta-Analysis

Simple Summary

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer causes more aggressive progression of disease and poorer outcomes for patients. HER2-targeted medicines used as neoadjuvant systemic therapy could improve clinical outcomes in early-stage or locally advanced breast cancer patients. The purpose of this systematic review and network meta-analysis was to identify the neoadjuvant anti-HER2 therapy with the best balance between efficacy and safety. We found that trastuzumab emtansine + pertuzumab + chemotherapy had a high pathologic complete response with a low risk of adverse events compared to other neoadjuvant anti-HER2 regimens, while the pertuzumab + trastuzumab + chemotherapy regimen showed the highest disease-free survival. However, further trial data on neoadjuvant regimens with trastuzumab emtansine are needed to confirm these findings.

Abstract

This systematic review aimed to identify neoadjuvant anti-human epidermal growth factor receptor 2 (HER2) therapies with the best balance between efficacy and safety. Methods: A network meta-analysis was applied to estimate the risk ratios along with 95% confidence intervals (CIs) for pathological complete response (pCR) and serious adverse events (SAE). A mixed-effect parametric survival analysis was conducted to assess the disease-free survival (DFS) between treatments. Results: Twenty-one RCTs with eleven regimens of neoadjuvant anti-HER2 therapy (i.e., trastuzumab + chemotherapy (TC), lapatinib + chemotherapy (LC), pertuzumab + chemotherapy (PC), pertuzumab + trastuzumab (PT), trastuzumab emtansine + pertuzumab (T-DM1P), pertuzumab + trastuzumab + chemotherapy (PTC), lapatinib + trastuzumab + chemotherapy (LTC), trastuzumab emtansine + lapatinib + chemotherapy (T-DM1LC), trastuzumab emtansine + pertuzumab + chemotherapy(T-DM1PC), PTC followed by T-DM1P (PTC_T-DM1P), and trastuzumab emtansine (T-DM1)) and chemotherapy alone were included. When compared to TC, only PTC had a significantly higher DFS with a hazard ratio (95% CI) of 0.54 (0.32–0.91). The surface under the cumulative ranking curve (SUCRA) suggested that T-DM1LC (91.9%) was ranked first in achieving pCR, followed by the PTC_T-DM1P (90.5%), PTC (74.8%), and T-DM1PC (73.5%) regimens. For SAEs, LTC, LC, and T-DM1LC presented with the highest risks (SUCRA = 10.7%, 16.8%, and 20.8%), while PT (99.2%), T-DM1P (88%), and T-DM1 (83.9%) were the safest regimens. The T-DM1PC (73.5% vs. 71.6%), T-DM1 (70.5% vs. 83.9%), and PTC_T-DM1P (90.5% vs. 47.3%) regimens offered the optimal balance between pCR and SAE. Conclusions: The T-DM1PC, T-DM1, and PTC_T-DM1P regimens had the optimal balance between efficacy and safety, while DFS was highest for the PTC regimen. However, these results were based on a small number of studies, and additional RCTs assessing the efficacy of regimens with T-DM1 are still needed to confirm these findings.

Comparing Biomarkers for Predicting Pathological Responses to Neoadjuvant Therapy in HER2-Positive Breast Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

The predictive strength and accuracy of some biomarkers for the pathological complete response (pCR) to neoadjuvant therapy for HER2-positive breast cancer remain unclear. This study aimed to compare the accuracy of the HER2-enriched subtype and the presence of PIK3CA mutations, namely, TILs, HRs, and Ki-67, in predicting the pCR to HER2-positive breast cancer therapy.

METHODS

We screened studies that included pCR predicted by one of the following biomarkers: the HER2-enriched subtype and the presence of PIK3CA mutations, TILs, HRs, or Ki-67. We then calculated the pooled sensitivity, specificity, positive and negative predictive values (PPVs and NPVs, respectively), and positive and negative likelihood ratios (LRs). Summary receiver operating characteristic (SROC) curves and areas under the curve (AUCs) were used to estimate the diagnostic accuracy.

RESULTS

The pooled estimates of sensitivity and specificity for the HER2-enriched subtype and the presence of PIK3CA mutations, namely, TILs, HRs, and Ki-67, were 0.66 and 0.62, 0.85 and 0.27, 0.49 and 0.61, 0.54 and 0.64, and 0.68 and 0.51, respectively. The AUC of the HER2-enriched subtype was significantly higher (0.71) than those for the presence of TILs (0.59, p = 0.003), HRs (0.65, p = 0.003), and Ki-67 (0.62, p = 0.005). The AUC of the HER2-enriched subtype had a tendency to be higher than that of the presence of PIK3CA mutations (0.58, p = 0.220). Moreover, it had relatively high PPV (0.58) and LR+ (1.77), similar NPV (0.73), and low LR- (0.54) compared with the other four biomarkers.

CONCLUSIONS

The HER2-enriched subtype has a moderate breast cancer diagnostic accuracy, which is better than those of the presence of PIK3CA mutations, TILs, HRs, and Ki-67.

Clinicopathological features of and neoadjuvant therapy for human epidermal growth factor receptor 2-positive classic invasive lobular carcinoma

Human epidermal growth factor receptor 2 (HER2)-positive classic invasive lobular carcinoma (ILC) is a rare entity, and its specific pathological characteristics and clinical behavior are unclear. Therefore, we retrospectively investigated the clinicopathological features of HER2-positive classic ILC and described HER2-targeted neoadjuvant chemotherapy outcome. Fourteen HER2-positive classic ILC cases were identified, their clinicopathological data were collected, and their clinical management was investigated. In general, HER2 positivity is associated with higher grade carcinoma in ductal lesions; however, our 14 cases had typical morphologic features of classic ILC. We did not identify unique morphologic features in HER2-positive classic ILC with the clinicopathological parameters examined, including age, menopausal status, histological grade, and hormone receptor status. Four of six patients who received HER2-targeted neoadjuvant chemotherapy had a pathological complete or partial response. Based on our findings, clinicopathological features of classic ILC may not predict HER2 overexpression or amplification. HER2-targeted neoadjuvant chemotherapy was effective against some HER2-positive classic ILCs. Taken together, these results demonstrate that HER2 immunohistochemistry and fluorescence in situ hybridization should be considered for all ILC patients regardless of subtype.

Efficacy and safety of neoadjuvant therapy for HER2-positive early breast cancer: a network meta-analysis

Aims:

Currently, there are many approaches available for neoadjuvant therapy for human epidermal growth factor receptor 2 (HER2)-positive breast cancer that improve therapeutic efficacy but are also controversial. We conducted a two-step Bayesian network meta-analysis (NMA) to compare odds ratios (ORs) for pathologic complete response (PCR) and safety endpoints.

Methods:

The Cochrane Central Register of Controlled Trials, PubMed, Embase, and online abstracts from the American Society of Clinical Oncology and San Antonio Breast Cancer Symposium were searched comprehensively and systematically. Phase II/III randomised clinical trials for targeted therapy in at least one arm were included.

Results:

A total of 9779 published manuscripts were identified, and 36 studies including 10,379 patients were finally included in our analysis. The NMA of PCR showed that dual-target therapy is better than single-target therapy and combination chemotherapy is better than monochemotherapy. However, anthracycline did not bring extra benefits, whether combined with dual-target therapy or single-target therapy. On the other hand, the addition of endocrine therapy in the HER2-positive, hormone receptor (HR)-positive subgroup might have additional beneficial effects but without significant statistical difference. By performing a conjoint analysis of the PCR rate and safety endpoints, we found that ‘trastuzumab plus pertuzumab’ and ‘T-DM1 containing regimens’ were well balanced in terms of efficacy and toxicity in all target regimens.

Conclusion:

In summary, trastuzumab plus pertuzumab-based dual-target therapy with combination chemotherapy regimens showed the highest efficacy of all optional regimens. They also achieved the best balance between efficacy and toxicity. As our study showed that anthracycline could be replaced by carboplatin, we strongly recommended TCbHP as the preferred choice for neoadjuvant treatment of HER2-positive breast cancer. We also look forward to the potential value of T-DM1 in improving outcomes, which needs further study in future trials.

Small-Molecule Drug Discovery in Triple Negative Breast Cancer: Current Situation and Future Directions

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, but an effective targeted therapy has not been well-established so far. Considering the lack of effective targets, where do we go next in the current TNBC drug development? A promising intervention for TNBC might lie in de novo small-molecule drugs that precisely target different molecular characteristics of TNBC. However, an ideal single-target drug discovery still faces a huge challenge. Alternatively, other new emerging strategies, such as dual-target drug, drug repurposing, and combination strategies, may provide new insight into the improvement of TNBC therapeutics. In this review, we focus on summarizing the current situation of a series of candidate small-molecule drugs in TNBC therapy, including single-target drugs, dual-target drugs, as well as drug repurposing and combination strategies that will together shed new light on the future directions targeting TNBC vulnerabilities with small-molecule drugs for future therapeutic purposes.

Pathologic and molecular responses to neoadjuvant trastuzumab and/or lapatinib from a phase II randomized trial in HER2-positive breast cancer (TRIO-US B07)

In this multicenter, open-label, randomized phase II investigator-sponsored neoadjuvant trial with funding provided by Sanofi and GlaxoSmithKline (TRIO-US B07, Clinical Trials NCT00769470), participants with early-stage HER2-positive breast cancer (N = 128) were recruited from 13 United States oncology centers throughout the Translational Research in Oncology network. Participants were randomized to receive trastuzumab (T; N = 34), lapatinib (L; N = 36), or both (TL; N = 58) as HER2-targeted therapy, with each participant given one cycle of this designated anti-HER2 therapy alone followed by six cycles of standard combination chemotherapy with the same anti-HER2 therapy. The primary objective was to estimate the rate of pathologic complete response (pCR) at the time of surgery in each of the three arms. In the intent-to-treat population, we observed similar pCR rates between T (47%, 95% confidence interval [CI] 30-65%) and TL (52%, 95% CI 38-65%), and a lower pCR rate with L (25%, 95% CI 13-43%). In the T arm, 100% of participants completed all protocol-specified treatment prior to surgery, as compared to 69% in the L arm and 74% in the TL arm. Tumor or tumor bed tissue was collected whenever possible pre-treatment (N = 110), after one cycle of HER2-targeted therapy alone (N = 89), and at time of surgery (N = 59). Higher-level amplification of HER2 and hormone receptor (HR)-negative status were associated with a higher pCR rate. Large shifts in the tumor, immune, and stromal gene expression occurred after one cycle of HER2-targeted therapy. In contrast to pCR rates, the L-containing arms exhibited greater proliferation reduction than T at this timepoint. Immune expression signatures increased in all arms after one cycle of HER2-targeted therapy, decreasing again by the time of surgery. Our results inform approaches to early assessment of sensitivity to anti-HER2 therapy and shed light on the role of the immune microenvironment in response to HER2-targeted agents.

Neoadjuvant Pyrotinib plus Trastuzumab and Chemotherapy for Stage I-III HER2-Positive Breast Cancer: A Phase II Clinical Trial

LESSONS LEARNED

This is the first trial to explore the neoadjuvant therapy of pyrotinib in HER2-positive operable and locally advanced breast cancer, in combination with epirubicin plus cyclophosphamide followed by docetaxel plus trastuzumab. Results primarily showed that pyrotinib in combination with epirubicin plus cyclophosphamide followed by docetaxel plus trastuzumab was effective and safe in HER2-positive operable and locally advanced breast cancer. A subsequent randomized controlled trial is still warranted to confirm these results.

BACKGROUND

The efficacy and safety of neoadjuvant therapy of pyrotinib, a new irreversible tyrosine kinase inhibitor (TKI), was first estimated in patients with HER2-positive breast cancer in this phase II study, in combination with trastuzumab and chemotherapy.

METHODS

Between February 19, 2019, and November 20, 2019, 20 female Chinese patients with stage I-III HER2-positive breast cancer were assigned to receive eight cycles of neoadjuvant pyrotinib (P) in combination with four cycles of epirubicin (E) and cyclophosphamide (C) followed by four cycles of docetaxel (T) and trastuzumab (H), once every 3 weeks, referred to as P + EC-TH.

RESULTS

A total of 19 patients completed the therapy and final surgery. The total pathological complete response (tpCR) rate was 73.7% (95% confidence interval [CI], 48.8-90.9), and no recurrence or metastasis occurred during the short-term follow-up period. The objective response rate (ORR) was 100% (95% CI, 82.4-100). The most common adverse events (AEs) were diarrhea and leukopenia in 18 of 20 patients (90%), but no grade 5 AEs were reported.

CONCLUSION

This study showed that in HER2-positive operable or locally advanced breast cancer, the tpCR rate of P + EC-TH neoadjuvant therapy was about twice as high as that of EC-TH neoadjuvant therapy reported in other trials, with tolerable side effects.

Repurposing of drugs for triple negative breast cancer: an overview

Breast cancer (BC) is the most frequent cancer among women in the world and it remains a leading cause of cancer death in women globally. Among BCs, triple negative breast cancer (TNBC) is the most aggressive, and for its histochemical and molecular characteristics is also the one whose therapeutic opportunities are most limited. The REpurposing Drugs in Oncology (ReDO) project investigates the potential use of off patent non-cancer drugs as sources of new cancer therapies. Repurposing of old non-cancer drugs, clinically approved, off patent and with known targets into oncological indications, offers potentially cheaper effective and safe drugs. In line with this project, this article describes a comprehensive overview of preclinical or clinical evidence of drugs included in the ReDO database and/or PubMed for repurposing as anticancer drugs into TNBC therapeutic treatments.

Ki-67 response-guided preoperative chemotherapy for HER2-positive breast cancer: results of a randomised Phase 2 study

BACKGROUND

The effectiveness of a therapeutic strategy that switches chemotherapy, based on Ki-67 tumour expression after initial therapy, relative to that of standard chemotherapy, has not been evaluated.

METHODS

Patients were randomly assigned to the control arm or the Ki-67 response-guided arm (Ki-67 arm). Primary tumour biopsies were obtained before treatment, and after three once-weekly doses of paclitaxel and trastuzumab to assess the interim Ki-67 index. In the control arm, paclitaxel and trastuzumab were continued for a total of 12 doses, regardless of the interim Ki-67 index. In the Ki-67 arm, subsequent treatment was based on the interim Ki-67 index. Ki-67 early responder is defined as the absolute Ki-67 value that was <10%, and the percentage of Ki-67-positive tumour cells was reduced by >30% compared with before treatment. Early Ki-67 responders continued to receive the same treatment, while early Ki-67 non-responders were switched to epirubicin plus cyclophosphamide. The primary endpoint was the pathological complete response (pCR) rate.

RESULTS

A total of 237 patients were randomised. There was almost linear correlation between the Ki-67 reduction rate at interim assessment and the pCR rate. The pCR rate in Ki-67 early non-responders in the Ki-67 arm was inferior to that in the control arm (44.1%; 31.4-56.7; P = 0.025).

CONCLUSIONS

The standard chemotherapy protocol remains as the recommended strategy for patients with HER2-positive breast cancer.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registration: UMIN-CTR as UMIN000007074.

Pathological Response to Neoadjuvant Chemotherapy and the Molecular Classification of Locally Advanced Breast Cancer in a Latin American Cohort

BACKGROUND

The majority of patients with breast cancer in Colombia are admitted into oncological centers at locally advanced stages of the disease (53.9%). The aim of this study was to describe the pathological response obtained with neoadjuvant chemotherapy (NACT) according to the molecular classification of breast cancer in patients with locally advanced tumors treated within the National Cancer Institute (NCI) Functional Breast Cancer Unit (FBCU) in Bogotá, Colombia.

MATERIALS AND METHODS

This was an observational, descriptive, historical cohort study of patients with locally advanced breast cancer treated within the NCI FBCU.

RESULTS

We included 414 patients who received NACT and surgical management. Most patients had luminal B HER2-negative tumors (n = 134, 32.4%). The overall rate of pathological complete response (pCR) ypT0/ypN0 was 15.2% (n = 63). Tumors that presented the highest rate of pCR were pure HER2, at 40.5% (n = 15; odds ratio [OR], 6.7); however, with a follow-up of 60 months, only the triple negative tumors presented a statistically significant difference for event-free survival (EFS; median recurrence time, 18 months; range, 1-46) and overall survival (OS; median follow-up, 31 months; range 10-57). The molecular subtype that most recurrences presented was luminal B HER2 negative, at 38.3% (n = 28). The majority of recurrences (93.2 %; n = 68; OR, 5.9) occurred in patients in whom no pathological response was obtained (Chevallier 3 and 4).

CONCLUSION

Pathological response in locally advanced tumors is related to the molecular subtype of breast cancer, finding higher pCR rates in pure HER2 and triple-negative tumors. A direct relationship was found between disease recurrences and the pathological response, evidencing greater tumor recurrence in patients who did not respond to NACT (Chevallier 3 and 4). EFS and OS were greater in patients with pCR, with statistical significance only in triple-negative tumors.

IMPLICATIONS FOR PRACTICE

This research article is of scientific interest, because it describes the clinical and pathological features and analyzes the correlation between pathological response to neoadjuvant chemotherapy and the molecular classification of locally advanced breast cancer in patients treated in the National Cancer Institute in Bogotá, Colombia. It was found that pathological response is related to the molecular subtype of breast cancer. In addition, there is a direct relationship between disease recurrences and pathological response. The survival results were greater in patients with pathological complete response.

Comedications influence immune infiltration and pathological response to neoadjuvant chemotherapy in breast cancer

Immunosurveillance plays an important role in breast cancer (BC) prognosis and progression, and can be geared by immunogenic chemotherapy. In a cohort of 1023 BC patients treated with neoadjuvant chemotherapy (NAC), 40% of the individuals took comedications mostly linked to aging and comorbidities. We systematically analyzed the off-target effects of 1178 concurrent comedications (classified according to the Anatomical Therapeutic Chemical (ATC) Classification System) on the density of tumor-infiltrating lymphocytes (TILs) and pathological complete responses (pCR). At level 1 of the ATC system, the main anatomical classes of drugs were those targeting the nervous system (class N, 39.1%), cardiovascular disorders (class C, 26.6%), alimentary and metabolism (class A, 16.9%), or hormonal preparations (class H, 6.5%). At level 2, the most frequent therapeutic classes were psycholeptics (N05), analgesics (N02), and psychoanaleptics (N06). Pre-NAC TIL density in triple-negative BC (TNBC) was influenced by medications from class H, N, and A, while TIL density in HER2⁺ BC was associated with the use of class C. Psycholeptics (N05) and agents acting on the renin-angiotensin system (C09) were independently associated with pCR in the whole population of BC or TNBC, and in HER2-positive BC, respectively. Importantly, level 3 hypnotics (N05C) alone were able to reduce tumor growth in BC bearing mice and increased the anti-cancer activity of cyclophosphamide in a T cell-dependent manner. These findings prompt for further exploration of drugs interactions in cancer, and for prospective drug-repositioning strategies to improve the efficacy of NAC in BC.

Correlation of circulating pro-angiogenic miRNAs with cardiotoxicity induced by epirubicin/cyclophosphamide followed by docetaxel in patients with breast cancer

OBJECTIVE

This study aimed to evaluate predictive value of 14 pro-angiogenic miRNAs for cardiotoxicity induced by epirubicin/cyclophosphamide follow by docetaxel (EC-D) in breast cancer (BC) patients.

METHODS

Three hundred and sixty-three BC patients receiving EC-D neoadjuvant chemotherapy were consecutively enrolled in this prospective cohort study. Peripheral blood sample was obtained from each patient, and plasma was separated. The expressions of 14 pro-angiogenic miRNAs, cardiac troponin I (cTnI) and N-terminal pro brain natriuretic peptide (NT-proBNP) were evaluated. Left ventricular ejection fraction (LVEF) level at C0, the end of 4 cycles of EC chemotherapy (C4), the end of 4 cycles of docetaxel treatment (C8), 3rd months (M3), 6th months (M6), 9th months (M9) and 12th months (M12) after surgery were assessed.

RESULTS

LVEF decreased at C4, C8, M3, M6, M9 and M12 compared with C0, and the total cardiotoxicity incidence was 5.2%. Additionally, the levels of let-7f, miR-17-5p, miR-20a, miR-126, miR-210 and miR-378 were reduced in cardiotoxicity patients. Multivariate logistic regression revealed that miR-17-5p and miR-20a were independently predictive factors for less cardiotoxicity. Receiver operating characteristics (ROC) curve displayed a satisfactory predictive value for lower cardiotoxicity risk with area under curve (AUC) of 0.842 of the combination of the miR-17-5p and miR-20a expressions. In addition, let-7f,miR-126, miR-210 and miR-378 levels negatively correlated with cTnI expression, and let-7f and miR-130a expressions reversely correlated with NT-proBNP level.CONLUSIONS: miR-17-5p and miR-20a could be served as biomarkers for lower cardiotoxicity induced by EC-D neoadjuvant chemotherapy in BC patients.

Comparative Efficacy and Tolerability of Neoadjuvant Immunotherapy Regimens for Patients with HER2-Positive Breast Cancer: A Network Meta-Analysis

This network meta-analysis addresses the need for evidence-based best-practice treatment regimens for HER2-positive breast cancer. We compared the relative efficacy and tolerability of currently available HER2-positive neoadjuvant immunotherapy regimens based on systematic searches of available randomized controlled trials (RCTs) data. Based on intention-to-treat principle, pathological complete response (pCR), overall serious adverse events (SAEs), and breast-conserving surgery (BCS) rate were analyzed using random-effect, Bayesian network meta-analysis, and standard pairwise meta-analysis. 16 RCTs (3868 patients) were included. Analyzed treatment regimens were as follows: chemotherapy+trastuzumab+pertuzumab (CTP), trastuzumab emtansine+pertuzumab (MP), chemotherapy+trastuzumab (CT), chemotherapy+pertuzumab (CP), trastuzumab+pertuzumab (TP), chemotherapy+trastuzumab+lapatinib (CTL), and chemotherapy+lapatinib (CL), and chemotherapy (C) alone. We found that, for the chance of achieving pCR, CTP was ranked first (SUCRA: 97%), followed by CTL, MP, and CT (SUCRA: 80%, 75%, and 55%, resp.). MP provided the safest regimen (SUCRA: 97%), then TP, C, and TPC (SUCRA: 82%, 76%, and 47%, resp.). CTL proved the most toxic therapy (SUCRA: 7%). No significant difference between neoadjuvant regimens was identified for BCS. Hormone receptor status did not impact ORs for pCR in any regimen. In conclusion, our findings support CTP as the optimum neoadjuvant regimen for HER2-positive breast cancer, with the best pCR and acceptable toxicity compared with CT. MP provides a therapeutic option for patients with poor performance status.

Celecoxib With Neoadjuvant Chemotherapy for Breast Cancer Might Worsen Outcomes Differentially by COX-2 Expression and ER Status: Exploratory Analysis of the REMAGUS02 Trial

PURPOSE

The overexpression of cyclooxygenase 2 (COX-2) gene, also known as prostaglandin-endoperoxide synthase 2 ( PTGS2), occurs in breast cancer, but whether it affects response to anticox drugs remains unclear. We investigated the relationships between PTGS2 expression, celecoxib use during neoadjuvant chemotherapy (NAC), and both event-free survival (EFS) and overall survival (OS).

MATERIALS AND METHODS

We analyzed a cohort of 156 patients with human epidermal growth factor receptor 2 -negative breast cancer from the REMAGUS02 (ISRCTN Registry No. 10059974) trial with pretreatment PTGS2 expression data. Patients were treated by sequential NAC (epirubicin plus cyclophosphamide followed by docetaxel with or without celecoxib). Experimental validation was performed on breast cancer cell lines. The Cancer and Leukemia Group B (CALGB) 30801 ( ClinicalTrials.gov identifier: NCT01041781) trial that tested chemotherapy with or without celecoxib in patients with lung cancer served as an independent validation cohort.

RESULTS

After 94.5 months of follow-up, EFS was significantly lower in the celecoxib group (hazard ratio [HR], 1.7; 95% CI, 1 to 2.88; P = .046). A significant interaction between PTGS2 expression and celecoxib use was detected ( P_interaction = .01). In the PTGS2-low group (n = 100), EFS was lower in the celecoxib arm (HR, 3.01; 95% CI, 1.45 to 6.24; P = .002) than in the standard treatment arm. Celecoxib use was an independent predictor of poor EFS, distant relapse-free survival, and OS. Celecoxib in addition to docetaxel enhanced cell viability in PTGS2-low cell lines but not in PTGS2-high cell lines. In CALGB 30801, a trend toward poorer progression-free survival was observed in the patients with low urinary metabolite of prostaglandin E2 who received celecoxib (HR = 1.57; 95% CI, 0.87 to 2.84; P = .13).

CONCLUSION

Celecoxib use during chemotherapy adversely affected survival in patients with breast cancer, and the effect was more marked in PTGS2-low and/or estrogen receptor-negative tumors. COX-2 inhibitors should preferably be avoided during docetaxel use in patients with breast cancer who are undergoing NAC.

Celecoxib in breast cancer prevention and therapy

Breast cancer has a high incidence worldwide. The results of substantial studis reveal that inflammation plays an important role in the initiation, development, and aggressiveness of many malignancies. The use of celecoxib, a novel NSAID, is repetitively associated with the reduced risk of the occurrence and progression of a number of types of cancer, particularly breast cancer. This observation is also substantiated by various meta-analyses. Clinical trials have been implemented on integration treatment of celecoxib and shown encouraging results. Celecoxib could be treated as a potential candidate for antitumor agent. There are, nonetheless, some unaddressed questions concerning the precise mechanism underlying the anticancer effect of celecoxib as well as its activity against different types of cancer. In this review, we discuss different mechanisms of anticancer effect of celecoxib as well as preclinical/clinical results signifying this beneficial effect.

Neoadjuvant chemotherapy in breast cancer: a dose-dense schedule in real life and putative role of PIK3CA mutations

Background

Dose-dense chemotherapy is one of the treatments of choice for neoadjuvant therapy in breast cancer (BC). Activating mutations in PIK3CA gene predict worse response to neoadjuvant chemotherapy for HER2-positive patients, while their role is less clearly defined for HER2-negative tumors.

Methods

We conducted a phase I/II study of neoadjuvant, sequential, dose-dense anthracycline/taxane chemotherapy, plus trastuzumab in HER2-positive patients and investigated the correlation of pre-treatment PIK3CA mutation status with pathologic complete response (pCR) and long-term outcome in a real-life setting.

Results

we established a dose-dense docetaxel recommended dose of 60 mg/m² and 65 mg/m², with or without trastuzumab, respectively, according to HER2-status, following dose-dense epirubicin-cyclophosphamide (90/600 mg/m²), every 2 weeks. The overall pCR rate was 21.4%; median disease-free survival (DFS) was 52 months and median overall survival (OS) was not yet reached. PIK3CA mutation status was not significantly associated with the pCR rate: 18% for both mutated and wild-type patients. The pCR rate was: 25% in the mutated and 24% in the wild-type (p 0.560) cohort of the HER2-positive subgroup; 33% both in the mutant and wild-type cohort of the triple-negative subgroup; no pCR neither in the mutant nor in the wild-type cohort of the HR-positive/HER2-negative subgroup. Among the HER2-positive population, a trend toward worse DFS was observed in case of mutation, as opposed to the triple negative population.

Conclusions

This study proposes an effective and safe neoadjuvant dose-dense anthracycline/taxane schedule and suggests that PIK3CA mutation analysis can be usefully performed in real-life clinical practice.

Combination of COX-2 expression and PIK3CA mutation as prognostic and predictive markers for celecoxib treatment in breast cancer

COX-2 expression level and prognostic value are still a matter of debate in breast cancer (BC). We addressed these points in the context of PIK3CA mutational status. Based on an interesting study of aspirin efficacy in colorectal cancer, we hypothesized that celecoxib antitumoral activity may be restricted to PIK3CA mutated BC.

COX-2 mRNA expression was analyzed in 446 BC samples and in 61 BC patient-derived xenografts (PDX) using quantitative RT-PCR. The prognostic impact of COX-2 expression level was assessed independently and according to PIK3CA mutational status in our cohort and in a validation set of 817 BC. The antitumoral activity of celecoxib was tested in two triple-negative (TN) PDX with a PIK3CA wild-type (wt) or mutated genotype.

COX-2 mRNA was overexpressed in 2% of BC and significantly associated with TN subtype. Metastasis-free survival (MFS) was significantly better in patients with high COX-2 expression level, the prognosis of whom was similar to patients with PIK3CA mutations. TCGA validation cohort confirmed that patients with low COX-2 expression PIK3CA wt tumors had the worse disease-free survival (DFS) compared to all other subgroups. Celecoxib had a significant antitumoral effect in PIK3CA mutated PDX only. Celecoxib antitumoral activity involved S6 ribosomal protein and AKT phosphorylation.

Low expression of COX-2 has a significant negative impact on the MFS/DFS of BC patients. Antitumoral effect of celecoxib is restricted to PIK3CA mutated PDX. These results suggest that PIK3CA mutation may be a new predictive biomarker for celecoxib efficacy.

The updated network meta-analysis of neoadjuvant therapy for HER2-positive breast cancer

BACKGROUND

We previously described a systematic assessment of the neoadjuvant therapies for human epidermal growth factor receptor-2 (HER2) positive breast cancer, using network meta-analysis. Accumulation of new clinical data has compelled us to update the analysis.

METHODS

Randomized trials comparing different anti-HER2 regimens in the neoadjuvant setting were included, and odds ratio for pathologic complete response (pCR) in seven treatment arms were assessed by pooling effect sizes. Direct and indirect comparisons using a Bayesian statistical model were performed. All statistical tests were two-sided.

RESULTS

A database search identified 993 articles with 13 studies meeting the eligibility criteria, including three new studies with lapatinib (lpnb). In an indirect comparison, dual anti-HER2 agents with CT achieved a better pCR rate than other arms. The credibility intervals of CT + tzmb + lpnb arm were largely reduced compared to our former report, which we added sufficient clinical evidence by this update. Values of surface under the cumulative ranking (SUCRA) suggested that CT + tzmb + pzmb had the highest probability of being the best treatment arm for pCR, widening the difference between the top two dual-HER2 blockade arms compared to our former report. The overall consistency with our first report enhanced the credibility of the results.

CONCLUSION

Network meta-analysis using new clinical data firmly establish that combining two anti-HER2 agents with CT is most effective against HER2-positive breast cancer in the neoadjuvant setting. New pzmb related trials are required to fully determine the best neoadjuvant dual-HER2 blockade regimen.

Impact of clinicopathological characteristics on the efficacy of neoadjuvant therapy in patients with human epidermal growth factor receptor-2-positive breast cancer

Neoadjuvant therapy has become increasingly common in human epidermal growth factor receptor-2 (HER2)-positive breast cancer. In this study, we examined the impact of different clinicopathological characteristics on pathological complete response (pCR) in patients treated with anti-HER2 agents. The PubMed and Embase databases were searched from inception through April 2017 to identify studies that met pre-specified criteria. The odds ratios (ORs) and 95% confidence intervals (CIs) were extracted directly or were calculated with other available information. Eleven randomized controlled trials (RCTs) that involved 3,269 HER2-positive women were included in this meta-analysis. Patients with hormone receptor (HR)-negative breast cancer benefited more from anti-HER2 therapy than did patients with HR-positive tumours (OR, 2.25; 95% CI, 1.93-2.62). Furthermore, this improvement in pCR was independent of anti-HER2 agents, phase, combined chemotherapy, neoadjuvant duration, year the trials started and region where the trials were conducted. Patients with small tumours achieved greater benefits than patients with large tumours (OR, 1.25; 95% CI, 1.00-1.55). Age did not predict an additional benefit from anti-HER2 neoadjuvant treatment (OR, 1.02; 95% CI, 0.73-1.45). The impact of nodal status on pCR was dependent on the anti-HER2 agents. In conclusion, for HER2-targeted neoadjuvant treatment in breast cancer, greater benefits were achieved in patients with small HR-negative tumours compared with patients with large HR-positive tumours. These results may improve drug development and treatment strategies, economic analyses and the design and interpretation of clinical trials.

[Impact of pathological complete response to neoadjuvant chemotherapy in invasive breast cancer according to molecular subtype]

OBJECTIVES

The aim of this study was to evaluate the impact of pathological complete response (pCR) on overall survival (OS) and recurrence-free survival (RFS) according to molecular subtypes in women treated for an invasive breast cancer after neoadjuvant chemotherapy (NAC).

METHODS

All women (n=225) managed with a neoadjuvant chemotherapy for an invasive breast cancer in our institution between January 2007 and December 2013 were included. The characteristics of patients with pCR (pCR-1), breast pCR and axillary pCR were compared to those without pCR (pCR-0) according to the molecular subtypes: luminal A (n=62), luminal B (n=77), Her-2 (n=31) and triple negative (n=55).

RESULTS

NAC concerned 225 patients of whom 36 (16%) had pCR. Achievement of pCR led to significantly better overall survival in women with Her-2 tumors (35% versus 100%, P=0.035) and also to significantly better locoregional survival in women treated for triple negative tumors (P=0.026). Predictive factors of pCR were a high pathologic grade: OR=2.39, IC 95% (1.19-4.83), P=0.008; Her-2 molecular subtype (P=0.008); positive estrogenic hormonal receptors (P=0.006), a positive Her-2 receptor: OR=2.58, IC 95% (1.20-5.54), P=0.01.

CONCLUSION

Achievement of pCR is an intermediate marker of survival in women managed with NAC for breast cancer.

The use of systemic therapies to prevent progression of inflammatory breast cancer: which targeted therapies to add on cytotoxic combinations?

INTRODUCTION

Inflammatory breast cancer is a rare but frequently fatal disease, essentially because of its high ability to develop distant metastases. Even though the prognosis of IBC was significantly improved by multimodal management, including the systematic use of cytotoxic-based induction, the prognosis remains largely dismal. Areas covered: This review presents the main achievements in the systemic treatment of IBC during the past 30 years. It focuses more specifically on recent results obtained with targeted therapies, including anti-HER2 and anti-angiogenic agents. Novel approaches under investigation are presented. Expert commentary: Current management of IBC is subtype-specific and the largest benefit has been achieved in HER2-positive disease. The identification of breakthrough therapeutic advances is eagerly awaited and will require the development of IBC-specific clinical trials. Future clinical investigations should not only aim to increase the pathological response rate but also to eradicate distant metastases, which ultimately lead to patient death.

Long-term outcome of the REMAGUS 02 trial, a multicenter randomised phase II trial in locally advanced breast cancer patients treated with neoadjuvant chemotherapy with or without celecoxib or trastuzumab according to HER2 status

BACKGROUND

The REMAGUS-02 multicenter randomised phase II trial showed that the addition to neoadjuvant chemotherapy (NAC) of trastuzumab in patients with localised HER2-positive breast cancer (BC) increased the pathological complete response (pCR) rate and that the addition of celecoxib in HER2-negative cases did not increase the pCR rate. We report here the long-term follow-up results for disease-free survival (DFS) and overall survival (OS).

PATIENTS AND METHODS

From 2004 to 2007, 340 stage II-III BC patients were randomly assigned to receive neoadjuvant EC-T (four cycles of epirubicin-cyclophosphamide followed by four cycles of docetaxel) +/- celecoxib in HER2-negative cases (n = 220) and ± trastuzumab in HER2-positive cases (n = 120). From September 2005, all patients with HER2-positive BC received adjuvant T (n = 106).

RESULTS

Median follow-up was nearly 8 years (94.4 months, 20-127 m). In the HER2-negative subgroup, addition of celecoxib was not associated with a DFS benefit. Favourable factors were smaller tumour size, expression of progesterone receptor status (PgR) and pCR. In the HER2-positive population, neoadjuvant trastuzumab was not associated with a DFS benefit. Axillary pCR was the only prognostic factor associated with DFS in this group [HR = 0.44, 95% CI = 0.2-0.97], p = 0.035]. To note, DFS and OS were significantly higher in the HER2-positive than in HER2-negative BC patients (HR = 0.58 [0.36-0.92], p = 0.021).

CONCLUSION

Celecoxib combined with NAC provided neither pCR nor survival benefit in patients with HER2-negative BC. Absence of PgR is a major prognostic factor. Neoadjuvant trastuzumab increased pCR rates without translation into a DFS or OS benefit compared with adjuvant trastuzumab only. Axillary pCR could be a more relevant surrogate of survival than in the breast in HER2-positive population. A retrospective comparison shows that patients with HER2-positive tumours have a better outcome than HER2-negative BC patients showing the impact of trastuzumab on the natural history of BC.

Bringing 3D tumor models to the clinic - predictive value for personalized medicine

Current decision-guiding algorithms in cancer drug treatment are based on decades of research and numerous clinical trials. For the majority of patients, this data is successfully applied for a systemic disease management. For a number of patients however, treatment stratification according to clinically based risk criteria will not be sufficient. The most effective treatment options are ideally identified prior to the start of clinical drug therapy. This review will discuss the implementation of three-dimensional (3D) cell culture models as a preclinical testing paradigm for the efficacy of clinical cancer treatment. Patient tumor-derived cells in 3D cultures duplicate the individual tumor microenvironment with a minimum of confounding factors. Clinical implementation of such personalized tumor models requires a high quality of methodological and clinical validation comparable to other biomarkers. A non-systematic literature search demonstrated the small number of prospective studies that have been conducted in this area of research. This may explain the current reluctance of many physicians and insurance providers in implementing this type of assay into the clinical diagnostic routine despite potential benefit for patients. Achieving valid and reproducible results with a high level of evidence is central in improving the acceptance of preclinical 3D tumor models.

HER2-Orientated Therapy in Early and Metastatic Breast Cancer

Due to the enhanced understanding of molecular oncology and signaling pathways in breast cancer (BC), therapy management has undergone a major transformation, especially with the emergence of treatment tailored to individual disease characteristics. In the case of HER2-positive early or metastatic BC, targeted therapies are well established and remain a major focus of ongoing research. The introduction of anti-HER2 biologicals such as trastuzumab, pertuzumab, and T-DM1 has made targeted and personalized treatment possible and has clearly improved disease-free and overall survival in patients with HER2-positive BC. Moreover, neoadjuvant chemotherapy represents a well-established and often favored option for patients with operable BC and a clear indication for postoperative chemotherapy (such as HER2-positive BC). Other trials are trying to identify additional surrogate markers for therapy response and clinical outcome in the neoadjuvant setting and that way open up new perspectives with a possible de-escalation of classical treatment in favor of targeted therapy.

BIRC5 (survivin): a pejorative prognostic marker in stage II/III breast cancer with no response to neoadjuvant chemotherapy

PURPOSE

Neoadjuvant systemic therapy (NAC) is currently used in the treatment of stage II/III breast cancer. Pathological complete response as a surrogate endpoint for clinical outcomes is not completely validated for all subgroups of breast cancers. Therefore, there is a need for reliable predictive tests of the most effective treatment.

METHODS

We used a combination of predictive clinical, pathological, and gene expression-based markers of response to NAC in a prospective phase II multicentre randomized clinical trial in breast cancer patients, with a long follow-up (8 years). This study concerned the subpopulation of 188 patients with similar levels of pathological response rates to sequential epirubicin/cyclophosphamide and docetaxel to determine predictive marker of pCR and DFS. We used a set of 45 genes selected from high throughput analysis and a standardized RT-qPCR. We analyzed the predictive markers of pathological complete response (pCR) and DFS in the overall population and DFS the subpopulation of 159 patients with no pCR.

RESULTS

In the overall population, combining both clinical and genomic variables, large tumor size, low TFF1, and MYBL2 overexpression were significantly associated with pCR. T4 Stage, lymphovascular invasion, negative PR status, histological type, and high values of CCNB1 were associated with DFS. In the no pCR population, only lymphovascular invasion and high values of BIRC5 were associated with DFS.

CONCLUSIONS

We confirm the importance of ER-related and proliferation genes in the prediction of pCR in NAC-treated breast cancer patients. Furthermore, we identified BIRC5 (survivin) as a main pejorative prognostic factor in patients with breast cancers with no pCR. These results also open perspective for predictive markers of new targeted therapies.

[Not Available]

NEOADJUVANT CHEMOTHERAPY IN HER2-POSITIVE AND TRIPLE-NEGATIVE BREAST CANCER: Neoadjuvant chemotherapy is a standard option in the management of operable breast cancer, as effective as adjuvant chemotherapy in term of survival and with the potential to increase the rate of breast conservation. In HER2+ and triple-negative breast cancers, neoadjuvant chemotherapy is associated with a high probability of pathological complete response, which strongly predicts survival outcome. In HER2+ breast cancer, trastuzumab, in combination with neoadjuvant chemotherapy, mostly anthracyclines and taxane-based, demonstrated a significant increase in pathological complete response rate. Recently, dual HER2 blockade strategies (lapatinib-trastuzumab or pertuzumab-trastuzumab) demonstrated a significant improvement in terms of pathological complete response over trastuzumab. In triple-negative breast cancer, recent data indicate that incorporating platinum compounds to neoadjuvant chemotherapy also significantly improves this parameter. Yet, in both subtypes, whether these substantial improvements may lead to significant benefits in terms of survival and breast conserving surgery remains to be demonstrated.

New insights on PI3K/AKT pathway alterations and clinical outcomes in breast cancer

PI3K/AKT signaling pathway plays an important role in tumorigenesis and regulates critical cellular functions including survival, proliferation and metabolism. PIK3CA mutations and AKT activation by phosphorylation (pAKT) are often detected in many cancers and especially at high frequencies in breast cancer. Mounting data suggest that PIK3CA mutations or pAKT are mostly associated with better or insignificant outcomes in estrogen receptor-positive (ER+) early stage breast cancer and tend to be with worse prognosis in ER- disease. pAKT expression has been identified to predict paclitaxel chemotherapy benefit in node-positive breast cancer. Preclinical and neoadjuvant trial data suggest that PIK3CA alterations confer resistance to HER2-targeted therapy and are associated with lower pathological complete response (pCR) rate in HER2-positive breast cancer. However, recent results from randomized clinical trials of adjuvant and metastatic settings show that patients with mutant and wildtype PIK3CA tumors derived similar benefit from anti-HER2 therapy. This article, with our new insights, aims to decipher the mixed data and discusses the influence of the potential confounding factors in the assessments. We also share our views for validation of PI3K/AKT alterations in relation to clinical outcome in the context of specific breast cancer subtypes and treatment modalities towards further advance of the precision medicine for breast cancer treatment.

An optimal stratified Simon two-stage design

In Phase II oncology trials, therapies are increasingly being evaluated for their effectiveness in specific populations of interest. Such targeted trials require designs that allow for stratification based on the participants' molecular characterisation. A targeted design proposed by Jones and Holmgren (JH) Jones CL, Holmgren E: ‘An adaptive Simon two‐stage design for phase 2 studies of targeted therapies’, Contemporary Clinical Trials 28 (2007) 654‐661.determines whether a drug only has activity in a disease sub‐population or in the wider disease population. Their adaptive design uses results from a single interim analysis to decide whether to enrich the study population with a subgroup or not; it is based on two parallel Simon two‐stage designs. We study the JH design in detail and extend it by providing a few alternative ways to control the familywise error rate, in the weak sense as well as the strong sense. We also introduce a novel optimal design by minimising the expected sample size. Our extended design contributes to the much needed framework for conducting Phase II trials in stratified medicine. © 2016 The Authors Pharmaceutical Statistics Published by John Wiley & Sons Ltd

Efficacy, safety and administration timing of trastuzumab in human epidermal growth factor receptor 2 positive breast cancer patients: A meta-analysis

Trastuzumab has been demonstrated to be an effective treatment in patients with human epidermal growth factor receptor-2 (HER-2) positive breast cancer (BC); however, inconsistent results with regards to the long-term survival benefits, safety and optimal administration timing of trastuzumab exist. The present meta-analysis investigated these inconsistencies in patients with HER-2 positive BC that received adjuvant or neoadjuvant trastuzumab. Computerized and manual searches were used to identify eligible randomized control trials (RCTs) to include in the analysis. Based on a fixed or random effects model, hazard and risk ratios were calculated and used to assess the survival advantages and risks of trastuzumab. A total of 14,546 patients from 13 RCTs were included in the analysis; 9 RCTs used an adjuvant setting and 4 RCTs used a neoadjuvant setting. Analysis of RCTs with an adjuvant setting demonstrated that treatment with trastuzumab and chemotherapy in patients with HER-2 positive BC, in comparison with patients receiving chemotherapy alone, improved disease-free survival, overall survival and overall response. However, a higher incidence of neutropenia (P<0.0001), leukopenia (P<0.0001), diarrhea (P=0.002), skin/nail change (P=0.02), left ventricular ejection fraction reduction (P=0.007) and congestive heart failure (P<0.00001) was observed. Notably, the incidence of mortality and cardiac toxicity following concurrent and weekly use of trastuzumab was significantly lower compared to treatment with trastuzumab sequentially and every 3 weeks, respectively. Additionally, trastuzumab improved the pathologic complete response with no additional toxicity in the neoadjuvant setting. The present meta-analysis summarizes that trastuzumab is efficacious in patients with HER-2 positive BC in adjuvant and neoadjuvant settings. Thus, concurrent and weekly administration of trastuzumab is preferable to treatment with trastuzumab sequentially and every 3 weeks. These findings should be considered when using trastuzumab in future clinical practice.

High HER2/Centromeric Probe for Chromosome 17 Fluorescence In Situ Hybridization Ratio Predicts Pathologic Complete Response and Survival Outcome in Patients Receiving Neoadjuvant Systemic Therapy With Trastuzumab for HER2-Overexpressing Locally Advanced Breast Cancer

BACKGROUND

The present study was performed to determine whether the human epidermal growth factor receptor-related 2 (HER2)/centromeric probe for chromosome 17 fluorescence in situ hybridization (FISH) ratio is a predictor of a pathologic complete response (pCR), recurrence-free survival (RFS), and/or overall survival (OS) in patients receiving neoadjuvant systemic treatment (NST) with trastuzumab (NST-T) for HER2+ locally advanced breast cancer (LABC).

PATIENTS AND METHODS

The present retrospective study included 555 patients with HER2+ LABC who had undergone NST and definitive surgery (1999-2012); 373 had concurrently received trastuzumab. HER2-positivity was considered present with an immunohistochemical score of 3+ and/or HER2 FISH ratio of ≥2.0. We used logistic regression analysis and Cox proportional hazard modeling to determine whether a high HER2 FISH ratio, either as a continuous variable or with a cutoff of ≥7.0, would predict for pCR (no invasive disease in the breast and no tumor in the ipsilateral axillary lymph nodes), RFS, and/or OS.

RESULTS

The pCR group's median HER2 FISH ratio was significantly higher than that of the non-pCR group (6.4 vs. 5.2; p = .003). The logistic regression model demonstrated that the independent predictors of pCR included a high HER2 FISH ratio as a continuous variable (p = .04). The multicovariate Cox proportional hazard model showed that a high HER2 FISH ratio (with a cutoff of ≥7.0 or as a continuous variable) was a significant prognostic indicator of longer RFS time (p = .047 and p = .04, respectively). Similarly, a high HER2 FISH ratio of ≥7.0 was associated with longer OS (p = .06).

CONCLUSION

A high HER2 FISH ratio is a predictor of pCR in patients with HER2+ LABC who receive NST-T.

IMPLICATIONS FOR PRACTICE

This study demonstrated the optimal predictive and prognostic value of a HER2/centromeric probe for chromosome 17 FISH ratio for primary HER2+ breast cancer treated with trastuzumab combined with neoadjuvant systemic treatment (NST-T). This suggests that a high HER2 FISH ratio is a potential indicator for a high pathologic complete response rate and a better prognosis when patients are treated with NST-T.

Magnetic resonance examination to predict pathological complete response following neoadjuvant chemotherapy: when is it appropriate for HER2-positive and triple-negative breast cancers?

BACKGROUND

To clarify appropriate timing for magnetic resonance examination to predict pathological complete response to neoadjuvant chemotherapy for patients with human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancers in terms of tumor volume change.

METHODS

Between September 2009 and December 2014, 113 women with HER2-positive (n = 51) and triple-negative (n = 62) invasive breast cancers undergoing neoadjuvant chemotherapy were enrolled. Patients with HER2-positive tumors underwent neoadjuvant chemotherapy with an anthracycline-based regimen followed by docetaxel with trastuzumab. Patients with triple-negative tumors underwent neoadjuvant chemotherapy with anthracycline-based (first in most cases) and taxane-based regimens. Magnetic resonance imaging was performed before neoadjuvant chemotherapy, between the regimens (midpoint examination), and after neoadjuvant chemotherapy (final examination). Response ratio of tumor volume was calculated and receiver-operating characteristic analyses for them for both subtypes were performed at the midpoint and final examinations.

RESULTS

Twenty-eight women with HER2-positive tumors (54.9 %) and 29 women with triple-negative tumors (46.8 %) had pathological complete response. The response ratios were better in cases with pathological complete response than in those without (p = 0.0341, p < 0.0001). The area under the curve at the final examination was higher than that at the midpoint examination for HER2-positive tumors (p = 0.039); whereas for the triple-negative tumors, no significant difference between the two examinations was shown (p = 0.5218).

CONCLUSIONS

Magnetic resonance examination to predict pathological complete response would be feasible after completion of a regimen including trastuzumab for HER2-positive tumors and at the midpoint of neoadjuvant chemotherapy for triple-negative tumors.

New directions in the neoadjuvant treatment of HER2+ breast cancer

Approximately 20% of breast cancer demonstrates amplification of the HER2 gene resulting in overexpression of the HER2 protein on the cell surface. Effective targeting with anti-HER2 monoclonal antibodies (trastuzumab, pertuzumab, trastuzumab-emtansine) and tyrosine kinase inhibitors (lapatinib) dramatically improves the natural history of this aggressive disease. Patients with HER2-overexpressing breast cancer (HER2+) achieve higher rates of pathologic complete response (pCR) to cytotoxic chemotherapy and HER2-targeted therapy in neoadjuvant trials compared with less aggressive subtypes. Moreover, a trend toward a positive correlation between pCR and improved long-term survival appears to be emerging in neoadjuvant clinical trials. This article reviews the various definitions of pCR as an end point in neoadjuvant clinical trials and summarizes the use of anti-HER2-targeted agents in the neoadjuvant setting for HER2+ disease.

Targeted Therapies in Breast Cancer: Implications for Advanced Oncology Practice

The systemic therapeutic management of breast cancer has undergone significant transformation in the past decade. Without targeted therapies, conventional treatment with cytotoxic agents has reached the limit of its potential in terms of patient survival for most types of cancer. Enhanced understanding of the pathogenesis of tumor cell growth and metastasis has led to the identification of signaling growth pathways as targets for these directed therapies. Novel therapies targeted to HER2/neu, epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), poly(ADP ribose) polymerase (PARP), mammalian target of rapamycin (mTOR), histone deacetylase (HDAC), the heat shock protein, and cyclin-dependent kinase (CDK) inhibitors have been developed and have demonstrated some efficacy in breast cancer. Recognition and management of the toxicities associated with targeted therapies is imperative. This review will describe the clinical development and utilization of targeted therapies currently in use or in clinical trials, with a focus on considerations for the oncology advanced practitioner.

Targeting the COX-2 Pathway to Improve Therapeutic Response in the Obese Breast Cancer Patient Population

Multiple studies have demonstrated that obesity is associated with a worse outcome for all breast cancer subtypes and that obese breast cancer patients do not respond as well as normal weight patients to aromatase inhibitor treatment and chemotherapy. While a number of mechanisms have been proposed to explain this link, recent studies have provided evidence that elevated local cyclooxygenase-2 (COX-2) expression and the resulting increase in prostaglandin E2 (PGE2) production may play an important role. COX-2 upregulation in breast tumors is associated with a poor prognosis, a connection generally attributed to PGE2's direct effects on apoptosis and invasion as well as its stimulation of pre-adipocyte aromatase expression and subsequent estrogen production. Research in this area has provided a strong foundation for the hypothesis that COX-2 signaling is involved in the obesity-breast cancer link, and further study regarding the role of COX-2 in this link is warranted.

Can pathologic complete response (pCR) be used as a surrogate marker of survival after neoadjuvant therapy for breast cancer?

Breast cancer is heterogeneous in clinical, morphological, immunohistochemical and biological features, as reflected by several different prognostic subgroups. Neoadjuvant approaches are currently used for the "in vivo" efficacy assessment of treatments. Pathological complete response (pCR) has been reported as a reliable predictive factor of survival in that setting. However, pCR remains a subject of controversy in terms of definition and its evaluation methods. In addition, its predictive value for patient outcome in various breast cancer biological subtypes has been under debate. In this review, we will present the existing definitions of pCR, the impact of its evaluation methods on its rate and the assessment of its predictive value for patient outcome in the molecular subtypes of breast cancer (luminal A and B, Triple Negative and HER2-positive).

Balancing activity and tolerability of neoadjuvant paclitaxel- and docetaxel-based chemotherapy for HER2-positive early stage breast cancer: sensitivity analysis of randomized trials

Paclitaxel and docetaxel represent the most adopted taxanes in the neoadjuvant treatment of HER2-positive breast cancer. Questions still remain with regard to their difference in terms of activity and tolerability. Events for pathological complete response (pCR), severe and febrile neutropenia (FN), and severe neurotoxicity were pooled by adopting a fixed- and random-effect model. A sensitivity analysis to test for the interaction between paclitaxel and docetaxel was accomplished. Absolute differences with 95% confidence intervals (CIs) and the number of patients needed to treat/harm (NNT/NNH) were calculated to derive the Likelihood of being Helped or Harmed (LHH). Data from 15 trials (3601 patients) were included. Paclitaxel significantly increases pCR rate by 6.8% in comparison with docetaxel (43.4%, 95% CI 41.1-45.7% versus 36.6%, 95% CI 34.3-39.0%, p=0.0001), regardless of the chemotherapy backbone, with an absolute difference of 9% and 9.2% for anthracycline-based or free-regimens. Paclitaxel significantly improves pCR versus docetaxel with a single HER2-inhibition by 6.7% (p=0.0012), with no difference if combined with a dual HER2-inhibition. Severe neutropenia and FN are significantly lower with paclitaxel, with an absolute difference of 32.4% (p<0.0001) and 2.5% (p=0.0059), respectively. Conversely, severe neurotoxicity is slightly higher with paclitaxel (3%, p=0.0001). The LHH ratio calculated for pCR and severe neutropenia is 2.0 and 0.7 for paclitaxel and docetaxel. Although the activity of neoadjuvant paclitaxel and docetaxel HER2-positive breast cancer is considered similar, the slight advantage in pCR, the significantly lower neutropenia and FN, do favor paclitaxel (in the weekly fashion) over docetaxel, despite the slightly worst neurotoxicity.

Taxane and anthracycline based neoadjuvant chemotherapy for locally advanced breast cancer: institutional experience

BACKGROUND

The aim of this study was to assess the response rates (clinical and pathological ) with docetaxel and epirubicin combination chemotherapy and its effect on outcome.

MATERIALS AND METHODS

We retrospectively analysed locally advanced breast cancer (LABC) patients who received NACT from January 2008 to December 2012 in our tertiary care centre. LABC constituted 37% of all breast cancer cases and 120 patients fulfilled the eligibility criteria. The regimens used for NACT were, six cycles of DEC (docetaxel 75 mg/m2, epirubicin 75 mg/ m2, cyclophosphamide 500 mg/m2 on Day 1, 3 weekly) and a sequential regimen (4 cycles of FEC, 5-flurouracil 600 mg/m2, epirubicin 75 mg/m2, cyclophosphamide 600 mg/m2 followed by 4 cycles of docetaxel 85 mg/m2).

RESULTS

The median age was 47 years (range 23-72). Ninety six ( 80 %) had T4 disease and 90% had clinically palpable lymph nodes at diagnosis. The median size of primary tumor at presentation was 5.9 cm. Hormone receptor positivity was seen in 55% and HER2/neu positivity, in 25%. Triple negative breast cancers constituted 25 % of the cases. The overall clinical response rate ( complete or partial ) was 85% and pathological complete responses were obtained in 15%. Four cases defaulted, 5 patients died of treatment related toxicity and 15% developed febrile neutropenia on DEC. The median duration of follow up was 22 months. The median time to relapse was 20 months and the 3 year relapse free and overall survival rates were 50% and 70% respectively.

CONCLUSIONS

LABC constituted 37% of all breast cancer cases at our institute. With NACT, pCR was seen in 15% of the cases. Sequential chemotherapy was better tolerated than concurrent anthracyline and taxane chemotherapy with a similar pCR.

Neoadjuvant therapy for breast cancer

Neoadjuvant treatment of breast cancer refers to the use of different treatment modalities prior to surgical excision of the tumor. It has been accepted as a treatment option for patients with nonmetastatic disease, because it renders inoperable tumors operable and increases the rates of breast-conserving surgery, while achieving similar long-term clinical outcomes as adjuvant treatment. The neoadjuvant setting is being increasingly perceived as a research platform, where the biologic effects of traditional anticancer agents can be delineated, prognostic and predictive biomarkers can be identified, and the development of targeted agents can be expedited. Surrogate endpoints that can predict long-term clinical outcome and are evaluable early on, such as the pathologic complete response, offer valuable opportunities for rapid assessment of anticancer agents. Additionally, efforts for molecular profiling of the post-neoadjuvant residual disease hold the potential to lead to personalized therapy for breast cancer patients with early-stage high-risk disease.

Neoadjuvant chemotherapy in breast cancer: what questions remain?

PURPOSE OF REVIEW

Although neoadjuvant therapy (NAT) has become a popular approach in the systemic management of breast cancer, several important clinical questions remain unanswered. In this article, we review the literature pertaining to these questions and discuss the management strategies based on our findings.

RECENT FINDINGS

Currently, the optimal duration of NAT is unclear. At this time, there is no compelling data to support the extension of traditional neoadjuvant chemotherapy regimens. In patients with triple-negative breast cancer, pathologic complete response may be prognostic and the appropriate use of neoadjuvant chemotherapy is crucial to achieve improved survival. In human epidermal growth factor receptor 2 (HER2)-positive disease, it is reasonable to consider dual blockade with trastuzumab and pertuzumab in combination with a taxane in the neoadjuvant setting. Finally, there is currently no evidence to support the use of further adjuvant chemotherapy in those patients with residual disease after NAT.

SUMMARY

There remain many unanswered questions with the use of neoadjuvant chemotherapy in breast cancer, and further randomized clinical trials are needed. The results of these trials will permit the clinicians to develop 'personalized' treatment approaches, thus giving women the best chance of survival.

Comparative effectiveness of neoadjuvant therapy for HER2-positive breast cancer: a network meta-analysis

BACKGROUND

The growing number of antihuman epidermal growth factor receptor-2 (HER2) agents suggests the need for defining the optimal choice of neoadjuvant therapy for HER2-positive breast cancer. This study aims to assess the efficacy and safety of neoadjuvant therapy for HER2-positive breast cancer.

METHODS

Randomized trials that compared different anti-HER2 regimens in the neoadjuvant setting were included. The odds ratio (OR) for pathological complete response (pCR), treatment completion, and safety was utilized for pooling effect sizes. Network meta-analysis using a Bayesian statistical model was performed to combine the direct and indirect evidence of neoadjuvant therapy for HER2-positive breast cancer. All statistical tests were two-sided.

RESULTS

A database search identified 1047 articles, with 10 studies meeting the eligibility criteria. A total of 2247 patients in seven different treatment arms were assessed. Anti-HER2 agents evaluated included trastuzumab (tzmb), lapatinib (lpnb), and pertuzumab (pzmb). Network meta-analysis showed no statistically significant difference between dual targeting treatment arms; however, lpnb reduced treatment completion due to adverse events. Patients in dual targeting arms had statistically significantly more pCR than those in other treatment arms (chemotherapy [CT] + tzmb + pzmb vs CT + tzmb, OR = 2.29, 95% credibility interval = 1.02 to 5.02, P = .02). The surface under the cumulative ranking probability curve indicated that CT + tzmb + pzmb had the highest probability of being the best treatment arm in terms of pCR.

CONCLUSIONS

This study indicates that combining two anti-HER2 agents with CT is the most effective treatment modality in the neoadjuvant setting for HER2-positive breast cancer.