A randomized, 3-arm, neoadjuvant, phase 2 study comparing docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP), TCbHP followed by trastuzumab emtansine and pertuzumab (T-DM1+P), and T-DM1+P in HER2-positive primary breast cancer

Role of imaging based response assesment for adapting neoadjuvant systemic therapy for breast cancer: A systematic review

PURPOSE

The objective of this systematic review is to investigate the role of imaging in response monitoring during neoadjuvant systemic therapy (NST) for breast cancer and assess whether treatment modifications based on imaging response are implemented in clinical practice.

METHODS

A systematic review was conducted, analyzing five clinical practice guidelines and 147 clinical trial publications involving NST for breast cancer. The snowballing technique was employed, using a "start set" of clinical guidelines to trace relevant trials. Additionally, a PubMed search was conducted to identify trials published between 2023-2024. The review analyzed the use of imaging modalities, timing, and response criteria, and whether escalation, de-escalation, or change of treatment occurred based on imaging response.

RESULTS

Imaging was utilized in 81 % (119/147) of the trials, with ultrasound, MRI, and mammography being the most frequently employed modalities. Mid-treatment imaging was applied in 56 % (83/147) of the trials. However, only 15 % (22/147) of the trials implemented treatment modifications based on imaging response, highlighting the limited application of imaging response-guided therapy. No standardized imaging protocols or consistent response-guided treatment strategies were identified across the trials or clinical practice guidelines, with considerable variability in imaging methods, timing, and response criteria.

CONCLUSION

This systematic review underscores the critical need for standardized imaging protocols, response assessment criteria and image-guided treatment decisions. It is therefore evident that imaging for response monitoring during treatment should preferably be performed within clinical trials.

A Retrospective, Single-Center Study Comparing Neoadjuvant ACTHP vs. DCbHP in HER2-Positive Early Breast Cancer Patients

BACKGROUND

Neoadjuvant systemic therapy is the preferred treatment approach for stage II-III HER2-positive breast cancer (BC). Real-life data comparing regimens with or without anthracyclines combined with two HER2 drugs is lacking. We compared the efficacy and toxicity of two commonly used regimens.

METHODS

Retrospective data were collected on patients newly diagnosed with clinical stage II-III HER2-positive BC and treated at Sheba Medical Center, Israel, between September 2017 and June 2022 with either neoadjuvant DCbHP (docetaxel, carboplatin, trastuzumab, pertuzumab) or ACTHP (doxorubicin, cyclophosphamide, paclitaxel trastuzumab pertuzumab). PCR (pathological complete response) (ypT0/isN0) was evaluated in both cohorts and according to HER2 immunohistochemistry (IHC) staining (3+ or 2+ and fluorescence in situ hybridization [FISH] positive), estrogen receptor (ER), tumor size and nodal status. The toxicity indices evaluated were reductions in left ventricle ejection fraction (LVEF), dose reductions, hospitalizations and febrile neutropenia.

RESULTS

Here, 106 received ACTHP and 73 received DCbHP. Median age at diagnosis, ER status, HER2 IHC (2+/FISH pos or 3+) and nodal status were balanced. PCR occurred in 63.1% of patients, 67.0% and 57.5% in the ACTHP and DCbHP groups, respectively (p = 0.129). In patients with HER2 3+ IHC, pCR rates were significantly better with the ACTHP regimen than with DCbHP (83% vs. 62.9%, p < 0.039). No difference was observed among patients with HER2 +2 IHC FISH pos. Symptomatic LVEF decrease was observed in seven patients (6.6%) receiving ACTHP vs. none (0%) receiving DCbHP (p < 0.001).

CONCLUSIONS

PCR rates were similar overall between ACTHP and DCbHP; however, in the HER2 3+ subgroup, ACTHP demonstrated increased efficacy. DCbHP was significantly less cardiotoxic.

The optimal neoadjuvant treatment strategy for HR+/HER2 + breast cancer: a network meta-analysis

The efficacy of neoadjuvant therapy varies significantly with hormone receptor (HR) status for patients with human epidermal growth factor receptor 2 (HER2) positive breast cancer (BC). Despite extensive research on HER2 + BC, the optimal neoadjuvant strategy for HR+/HER2 + BC remains inconclusive. This study aimed to identify the optimal neoadjuvant regimen for HR+/HER2 + BC treatment. We conducted a systematic search for trials comparing neoadjuvant regimens for HR+/HER2 + BC and a network meta-analysis. Odds ratios for pathological complete response (pCR) and hazard ratios for event-free survival (EFS) were calculated. Treatment regimens were ranked using the surface under the cumulative ranking curve. 20 trials with 2809 patients were included. In pCR analysis, three neoadjuvant regimens sequentially ranked at the top, namely those comprising T-DM1, pertuzumab with trastuzumab, and tyrosine kinase inhibitor with trastuzumab, demonstrating significantly higher pCR rates than monotherapies. In EFS analysis, pertuzumab with trastuzumab ranked the first while T-DM1 containing regimen ranked the last. Anthracycline-free regimens showed a marginally higher pCR rate than anthracycline-containing regimens, while carboplatin-containing regimens demonstrated a numerically higher pCR rate than carboplatin-free regimens. Significant heterogeneity was observed in endocrine therapy analysis, which may be caused by different strategies for incorporating endocrine therapy. In conclusion, trastuzumab plus pertuzumab stands out as the optimal neoadjuvant HER2-targeting regimen for HR+/HER2 + BC Furthermore, anthracycline-free carboplatin-containing chemotherapy emerges as a promising combination treatment. Further investigation is required to clarify the role of endocrine therapy in HR+/HER2 + BC to guide its clinical application.

Long-term outcomes of neoadjuvant trastuzumab emtansine + pertuzumab (T-DM1 + P) and docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP) for HER2-positive primary breast cancer: results of the randomized phase 2 JBCRG20 study (Neo-peaks)

PURPOSE

The randomized phase 2 Neo-peaks study examined usefulness of neoadjuvant trastuzumab emtansine + pertuzumab (T-DM1 + P) following docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP) as compared with the standard TCbHP regimen. We previously reported that pCR rate after neoadjuvant therapy tended to be higher with TCbHP followed by T-DM1 + P. We conducted an exploratory analysis of prognosis 5 years after surgery.

METHODS

Neoadjuvant treatment with TCbHP (6 cycles; group A), TCbHP (4 cycles) followed by T-DM1 + P (4 cycles; group B), and T-DM1 + P (4 cycles; group C, + 2 cycles in responders) were compared. Group C non-responders after 4 cycles were switched to an anthracycline-based regimen. We evaluated 5-year disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS).

RESULTS

Data from 203 patients (50, 52, and 101 in groups A-C, respectively) were analyzed. No significant intergroup differences were found for DFS, DDFS, or OS. The 5-year DFS rates (95% CI) were 91.8% (79.6-96.8%), 92.3% (80.8-97.0%), and 88.0% (79.9-93.0%) in groups A-C, respectively. TCbHP followed by T-DM1 + P and T-DM1 + P with response-guided addition of anthracycline therapy resulted in similar long-term prognosis to that of TCbHP.

CONCLUSIONS

In patients who achieved pCR after neoadjuvant therapy with T-DM1 + P, omission of adjuvant anthracycline may be considered, whereas treatment should be adjusted for non-pCR patients with residual disease. T-DM1 + P with response-guided treatment adjustment may be useful for minimizing toxicity.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

UMIN-CTR, UMIN000014649, prospectively registered July 25, 2014. Some of the study results were presented as a Mini Oral session at the ESMO Breast Cancer 2023 (Berlin, Germany, 11-13 May 2023).

Use of Antibody-Drug Conjugates in the Early Setting of Breast Cancer

Antibody-drug conjugates (ADCs) are anticancer agents with the capacity to selectively deliver their payloads to cancer cells. Antibody-drug conjugates consist of a monoclonal antibody backbone connected by a linker to cytotoxic payloads. Antibody-drug conjugate effect occurs either by directly targeting cancer cells via membrane antigen or through "bystander effect." Antibody-drug conjugates have demonstrated efficacy against various types of tumors, including breast cancer. Ado-trastuzumab emtansine is presently the only approved ADC for the treatment of breast cancer in the early setting, while several ADCs are now approved for metastatic breast cancer. Due to the transformative impact that several ADCs have reported in the setting of advanced breast cancer, researchers are now testing more of such compounds in the early setting, to portend benefits to patients through highly potent anticancer drugs. Ongoing trials hold the potential to transform treatment protocols for early breast cancer in the near future. These trials are aiming at evaluating different treatment modulation approaches, as informed by breast cancer risk of recurrence, including toward treatment de-escalation. Efforts are provided in ongoing clinical trials to identify the patients who will benefit most, to pursue paradigms of precision medicine with the novel ADCs. This review focuses on the potential role of ADCs in early breast cancer, providing an overview of the latest progress in their development and how they are implemented in ongoing clinical trials.

Axillary Nodal Response to Neoadjuvant T-DM1 Combined with Pertuzumab in a Prospective Phase II Multi-Institution Clinical Trial

BACKGROUND

Patients with ERBB2 (HER2)-positive breast cancer experience high pathologic complete response (pCR) rates after standard neoadjuvant anti-HER2 systemic therapy. We examined axillary pathologic nodal response to neoadjuvant dual HER2-targeted therapy alone, based on breast pathologic response, in a multi-institution clinical trial.

STUDY DESIGN

Patients with HER2-positive breast cancer were enrolled to a phase II single-arm trial, which administered 6 cycles of neoadjuvant trastuzumab emtansine (T-DM1) plus pertuzumab. Rates of pathologic nodal disease (ypN) in patients who were clinically node-negative (cN0) and node-positive (cN1) were analyzed, by residual breast disease (pCR and residual cancer burden [RCB] I to III).

RESULTS

One hundred fifty-eight patients completed preoperative treatment and proceeded to surgery. Of 92 patients who were cN0, 48 (52.2%) and 10 (10.9%) experienced breast pCR and RCB I, respectively. Of these, 100% were ypN0. Of 34 with RCB II to III, 26 (76.5%) were ypN0. Of 30 patients who were cN1 with breast pCR, 100% were ypN0; of the 12 patients who were cN1 with RCB I, 66.7% were ypN0; and of the 24 patients who were cN1 with RCB II to III, 25% were ypN0. ypN0 rates were significantly different between patients who did and did not experience a pCR, in both cN0 (p = 0.002) and cN1 (p < 0.001) subgroups.

CONCLUSIONS

Patients with HER2-positive breast cancer treated with dual HER2-targeted therapy who experienced a breast pCR or RCB I response were frequently ypN0. These findings support future trials considering omission of axillary surgical staging for patients with HER2-positive breast cancer in neoadjuvant trials of active HER2-targeted regimens, particularly if they experience breast pCR or RCB I.

Real-world data on neoadjuvant chemotherapy with dual-anti HER2 therapy in HER2 positive breast cancer

BACKGROUND

Neoadjuvant chemotherapy with dual-targeted therapy is the standard treatment for human epidermal growth factor 2 (HER2)-positive breast cancer. Although the dual-targeted therapy has significantly improved the pathological complete response (pCR) rate, further investigation is needed to identify biomarkers that predict the response to neoadjuvant therapy.

METHODS

This retrospective study analyzed 353 patients with HER2-positive breast invasive ductal carcinoma. The correlation between clinicopathological factors and pCR rate was evaluated. A nomogram was constructed based on the results of the multivariate logistic regression analysis to predict the probability of pCR.

RESULTS

The breast pCR (b-pCR) rate was 56.1% (198/353) and the total pCR (t-pCR) rate was 52.7% (186/353). Multivariate analysis identified ER status, PR status, HER2 status, Ki-67 index, and neoadjuvant chemotherapy regimens as independent indicators for both b-pCR and t-pCR. The nomogram had an area under the receiver operating characteristic curve (AUC) of 0.73 (95% CI: 0.68-0.78). According to the nomogram, the t- pCR rate was highest in the ER-PR- HER2-positive patients (131/208) and lowest in the ER + PR + HER2-positive patients (19/73). The subgroup analyses showed that there was no significant difference in pCR rate among the neoadjuvant chemotherapy regimens in ER positive, PR positive, HER2 IHC 2 + , Ki67 index < 30% population. However, for ER-PR-HER2-positive patients, the neoadjuvant chemotherapy regimen has a great influence on the pCR rates.

CONCLUSIONS

Patients with ER-negative, PR-negative, HER2 3 + and high KI-67 index were more likely to achieve pCR. THP may be used as an alternative to AC-THP or TCbHP in selected HER2-positive patients.

Meta-analysis of the clinical efficacy and safety of T-DM1 in the treatment of HER2-positive breast cancer

ABSTRACT

This meta-analysis aims to comprehensively evaluate the efficacy and safety of T-DM1 in treating HER2-positive breast cancer, providing insights for clinical practice. We conducted a literature search in PubMed, Cochrane Library, and Embase databases up to September 2023, collecting randomized controlled trials and cohort studies on T-DM1 for HER2-positive breast cancer. Out of 316 initially retrieved articles, 12 studies meeting the quality and inclusion criteria were included after a rigorous screening process. We used RevMan 5.3 software for the meta-analysis, employing fixed or random-effect models. Odds ratios (RRs) and 95% confidence intervals (CIs) were calculated as effect size measures. We conducted sensitivity analyses and assessed publication bias to ensure the results' stability and reliability. In seven studies, T-DM1 treatment significantly prolonged OS in patients with HER2-positive breast cancer [hazard ratio (HR) = 0.70, 95% CI: 0.64-0.77, P < 0.01], and the effect was especially pronounced in patients with advanced disease (HR = 0.64, 95% CI: 0.54-0.76, P < 0.001). Analysis of pCR rates did not show a significant difference (OR = 0.91, 95% CI: 0.48-1.73, P = 0.77). In five studies, ORR improved, but the difference between the two groups was not significant (OR = 1.16, 95% CI: 0.66-2.05, P = 0.61). Analysis of progression-free survival (PFS) showed a significant improvement in the experimental group relative to the control group (HR = 0.69, 95% CI: 0.57-0.84, P = 0.0003). Regarding the incidence of total adverse events, no significant difference was seen between the two groups (OR = 2.16, 95% CI: 0.98-4.79, P = 0.06), but for specific adverse events, such as leukopenia and neutropenia, the T-DM1 group demonstrated a significant reduction relative to the other treatment regimens. The results underscore the potential of T-DM1 in enhancing survival among patients with advanced HER2-positive breast cancer, yet they also highlight variability in effectiveness concerning pCR rate and ORR. The findings on adverse effects underscore the necessity of a balanced consideration of T-DM1's risks and benefits. Future research should focus on a more detailed examination of responses in varied patient populations, long-term outcomes, and a thorough economic evaluation of T-DM1, along with an exploration into treatment resistance. This will provide a more nuanced understanding of T-DM1's role in the treatment landscape of HER2-positive breast cancer.

Neoadjuvant Chemotherapy of Taxanes With or Without Anthracyclines in Different Molecular Subtypes of Breast Cancer: A Propensity Score Matching Study

PURPOSE

To compare the efficacy of taxane (T) based neoadjuvant chemotherapy (NAC) with T and anthracycline (A) based NAC in different molecular types of breast cancer (BC).

METHODS

We retrospectively analyzed the date of NAC for BC from 20 hospitals in China from January 2010 to December 2020, 7870 cases were enrolled. The propensity score matching was used to equalize the baseline characteristics. Pathological complete response (pCR) rate, clinical response rate and breast-conserving rate were analyzed.

RESULTS

The efficacy of 2 regimens were similar in luminal A subtype. The breast-conserving rate was higher in T-based NAC in luminal B subtype (17.9% vs. 10.2%, P = .043).The pCR (T0/isN0M0) and tpCR (T0N0M0) rates in T-based NAC were higher than those in TA-based NAC for triple-negative subtype (pCR: 34.5% vs. 25.8%, P = .041, tpCR: 26.9% vs. 17.1%, P = .008). For HER2+(HR-) subtype, the pCR, and tpCR rates were higher in T-based NAC in insufficient anti-HER2 therapy (P < .05), and those were higher in TA-based NAC in dual-target anti-HER2 therapy (pCR: 69.2% vs. 53.8%, P = .254, tpCR: 61.5% vs. 42.3%, P = .165). For HER2+(HR+) breast cancer, both pCR and tpCR rates were higher in TA group, regardless of the adequacy of anti-HER2 treatment.

CONCLUSIONS

T-based NAC could replace TA-based NAC for luminal A, luminal B, and triple-negative early-stage BC, but anthracyclines cannot be abandoned in HER2+ breast cancer. The development of anthracyclines with lower adverse reactions is one of the directions for the treatment of HER2+ breast cancer.

PR status is a more decisive factor in efficacy of adding pertuzumab into neoadjuvant therapy for HER2-positive and lymph node-positive breast cancer than ER status: a real-world retrospective study in China

BACKGROUND

Although neoadjuvant trastuzumab and pertuzumab (HP)-based regimens are recommended for human epidermal receptor-positive (HER2 +)/lymph node-positive (N +) breast cancer (BC) patients according to NCCN guidelines, it is undeniable that many patients achieved pathological complete response (pCR) after trastuzumab (H)-based regimens without adding pertuzumab to treatment. Patients who specifically benefit from pertuzumab must be identified. The aim of this retrospective study was to evaluate progesterone receptor (PR) status as a predictor of response to the addition of pertuzumab in HER2 + /N + breast cancer.

METHODS

One hundred forty-two patients who were diagnosed as HER2 + /N + BC without distant metastasis and followed by neoadjuvant HP-based or H-based therapy were retrospectively included. The endpoints were pCR and disease-free survival (DFS) times.

RESULTS

In total, the pCR occurred in 25 of 87 patients (28.74%) in group H compared with 32 of 55 (58.18%) in group HP. The results revealed that hormone receptor (HR) status was significantly different on pCR in group HP. The odds of pCR for patients who have HR-positive tumors were 0.160 times (P = 0.011) that for patients with HR-negative tumors by multivariable analysis. Moreover, a similar probability of PR-positive (PR +) patients, whatever estrogen receptor (ER) status was, achieving pCR in group HP was observed. The ROC curves showed different anti-HER2 regimens provide worst predictive value in the PR + cohort (N = AUC = 0.521, 95% CI: 0.348-0.694, P = 0.813) compared with the overall cohort (AUC = 0.644, 95% CI: 0.550-0.738, P = 0.004) and ER + cohort (AUC: 0.559, 95% CI: 0.405-0.713, P = 0.451). And PR status (AUC = 0.760, 95% CI: 0.626-0.894, P = 0.001) had a greater predictive value than ER status (AUC = 0.658, 95% CI: 0.508-0.807, P = 0.048) in group HP. DFS analyses were done on 141 patients. Although ER and PR status did not show significant difference in group HP (P = 0.789 and 0.088, respectively), HP-based therapy contributed to better DFS in the ER - and PR - cohorts (P = 0.035 and 0.015, respectively).

CONCLUSIONS

Compared with ER status, PR status might be a more valuable factor predicting the efficacy of adding pertuzumab into neoadjuvant therapy for HER2 + /N + BC. PR + patients benefit little from the addition of pertuzumab.

Antibody-drug conjugates come of age in oncology

Antibody-drug conjugates (ADCs) combine the specificity of monoclonal antibodies with the potency of highly cytotoxic agents, potentially reducing the severity of side effects by preferentially targeting their payload to the tumour site. ADCs are being increasingly used in combination with other agents, including as first-line cancer therapies. As the technology to produce these complex therapeutics has matured, many more ADCs have been approved or are in late-phase clinical trials. The diversification of antigenic targets as well as bioactive payloads is rapidly broadening the scope of tumour indications for ADCs. Moreover, novel vector protein formats as well as warheads targeting the tumour microenvironment are expected to improve the intratumour distribution or activation of ADCs, and consequently their anticancer activity for difficult-to-treat tumour types. However, toxicity remains a key issue in the development of these agents, and better understanding and management of ADC-related toxicities will be essential for further optimization. This Review provides a broad overview of the recent advances and challenges in ADC development for cancer treatment.

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.

Axillary Downstaging and the Impact of Clinical Axillary Status on Efficacy of Neoadjuvant Therapy for HER2-Positive Breast Cancer: A Network Meta-Analysis

Background: Lymph node downstaging and the achievement of total-pCR (ypT0/is ypN0) after neoadjuvant therapy are of great importance in HER-2 positive breast cancer. We aim to provide an overall review of neoadjuvant regimens for lymph node downstaging and to indirectly compare the total-pCR by various neoadjuvant regimens with network meta-analysis in HER2-positive patients according to their clinical lymph node status. Methods: Five English databases were searched comprehensively and systematically for relevant RCTs and case-control studies. The data extracted from the included studies were analyzed with the use of Review Manager 5.3 or STATA 15.0 software. Results: A total of 1508 published manuscripts were identified, and 17 studies including 4747 patients were finally included in our analysis. The network meta-analysis of total-pCR showed that dual-target therapy is significantly better than single-target therapy in clinically node-positive patients, and carboplatin performed significantly better than anthracycline in single-target condition. Lapatinib performed poorly in clinically node-positive patients. However, lapatinib in combination with trastuzumab was ranked at the top in the clinically node-negative group, and pertuzumab showed dissatisfied performance in contrast to the primacy of pertuzumab in clinically node-positive groups. Conclusion: In summary, different lymph node statuses led to the diverse first choice of neoadjuvant regimen. We highly recommended TCbHP as the first choice for the neoadjuvant treatment in clinically node-positive HER-2 positive breast cancer. Since lapatinib with trastuzumab ranked top in the clinically node-negative group, we looked forward to discovering the potential value of TKI in clinically node-negative patients, which needs further analysis in the future.

Predicting Pathological Complete Response in Neoadjuvant Dual Blockade With Trastuzumab and Pertuzumab in HER2 Gene Amplified Breast Cancer

Background

Dual-targeted therapy is the standard treatment for human epidermal growth factor receptor 2 (HER2)-positive breast cancer, and effective biomarkers to predict the response to neoadjuvant trastuzumab and pertuzumab treatment need further investigation. Here, we developed a predictive model to evaluate the dual-targeted neoadjuvant treatment efficacy in HER2 gene-amplified breast cancer.

Method

This retrospective study included 159 HER2-amplified patients with locally advanced breast cancer who received neoadjuvant trastuzumab, pertuzumab, and chemotherapy. The correlation between clinicopathological factors and pathological complete response (pCR, in the breast and axilla) was evaluated. Patients were randomly assigned into the training set (n=110) and the testing set (n=49). We used an independent cohort (n=65) for external validation. We constructed our predictive nomogram model with the results of risk variables associated with pCR identified in the multivariate logistic analysis. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve, decision curve analysis, and calibration curves were employed to assess the nomogram's performance.

Results

We revealed that the HER2/CEP17 ratio (p=0.001), CD8 levels (p=0.005), and histological grade (p=0.007) were independent indicators for pCR in dual-targeted neoadjuvant treatment after multivariate adjustment. The combined prediction efficacy of the three indicators was significantly higher than that of each single indicator alone. The AUCs were 0.819, 0.773, and 0.744 in the training, testing, and external validation sets, respectively.

Conclusions

The HER2/CEP17 ratio, CD8 levels, and histological grade were significantly correlated with pCR in dual-targeted neoadjuvant treatment. The combined model using these three markers provided a better predictive value for pCR than the HER2/CEP17 ratio, CD8 levels, and the histological grade alone, which showed that an immunological effect partially mediates the predictive impact of neoadjuvant treatment.

Extracellular Vesicles and Cell Pathways Involved in Cancer Chemoresistance

Chemoresistance is a pharmacological condition that allows transformed cells to maintain their proliferative phenotype in the presence of administered anticancer drugs. Recently, extracellular vesicles, including exosomes, have been identified as additional players responsible for the chemoresistance of cancer cells. These are nanovesicles that are released by almost all cell types in both physiological and pathological conditions and contain proteins and nucleic acids as molecular cargo. Extracellular vesicles released in the bloodstream reach recipient cells and confer them novel metabolic properties. Exosomes can foster chemoresistance by promoting prosurvival and antiapoptotic pathways, affecting cancer stem cells and immunotherapies, and stimulating drug efflux. In this context, a crucial role is played by membrane transporters belonging to ABC, SLC, and P-type pump families. These proteins are fundamental in cell metabolism and drug transport in either physiological or pathological conditions. In this review, different roles of extracellular vesicles in drug resistance of cancer cells will be explored.

Neoadjuvant pertuzumab in non‑metastatic HER2‑positive breast tumors: Multicentric study in Peru (NeoHer)

Several clinical trials have demonstrated the benefit of adding pertuzumab to trastuzumab plus neoadjuvant chemotherapy in the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The comparison of outcomes between nonrandomized groups of patients who received similar treatments in routine practice remains difficult. The present study aimed to evaluate the pathological complete response (pCR) rates achieved with pertuzumab among patients in routine clinical care in Peru using real-world data. The definition of pCR used was the absence of residual invasive cancer from the complete resected breast specimen and all sampled regional lymph nodes following completion of neoadjuvant systemic therapy. A total of 44 patients with non-metastatic HER2-positive breast cancer (stages II and III) treated with pertuzumab in the neoadjuvant setting and who underwent surgery at three private clinics in Lima (Peru) were retrospectively evaluated. The pCR was the efficacy endpoint and it was determined and compared with the results from other clinical trials. Furthermore, safety data were described. The median age was 44 years (interquartile range, 39.5-50.5 years) and 65.9% of patients were premenopausal. Regarding the clinical stage, 56.8% were IIA/IIB and 36.4% were IIIA/IIIB/IIIC. All treatment schemes included concurrent trastuzumab. The patients' treatment comprised neoadjuvant therapy of docetaxel/trastuzumab/pertuzumab (THP) with a median of 4 cycles in 30 patients (68.2%) or docetaxel/trastuzumab/pertuzumab/carboplatin (THPCarb) with a median of 6 cycles in 14 patients (31.8%). In total, 70.5% of patients experienced pCR; among hormone receptor-negative cases, 75.0% achieved pCR and in tumors expressing hormone receptors, the rate of pCR was 66.7%. Of those patients subjected to neoadjuvant treatment with THP, 66.7% (20/30) achieved pCR, whereas 78.6% (11/14) of patients who received THPCarb had a pCR. The incidence of drug-related adverse events was 59.1% and in none of the patients, administration was discontinued due to toxicity. The present results of Peruvian patients with HER2 breast cancer treated according to clinical routine demonstrated that dual blockade of HER2 with trastuzumab and pertuzumab in the neoadjuvant setting achieved high rates of pCR even in hormone receptor-positive patients. These results are consistent with those of randomized controlled trials, with a good safety profile.

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.

ErbB inhibitors as neoadjuvant therapy for triple-positive breast cancer: a network meta-analysis

BACKGROUND

Evidence on the effectiveness of ErbB inhibitor interventions for women with triple-positive breast cancer (TPBC) is scarce. Exposure to hormone receptors was reported to eclipse targeted intervention effectiveness. Here, we aimed to explore the optimum targeted regimen for TPBC.

METHODS

We conducted a thorough search of the literature focusing on neoadjuvant targeted therapy with both hormone receptor-positive and HER2 (ErbB2)-positive patients and performed a network meta-analysis comparing the regimens using a random-effects model. The rate of pathological complete response (pCR) (ypT0/is) was the primary outcome. The odds ratio (OR) with 95% confidence interval (CI) was used to assess the association among twelve regimens.

RESULTS

Thirteen studies meeting the inclusion criteria were included. Significantly more TPBC patients receiving ado-trastuzumab emtansine plus lapatinib experienced pCR events than other patients. In the high-performance ranking of the twelve regimens, ado-trastuzumab emtansine plus lapatinib (TDM-1+L) ranked top, followed by ado-trastuzumab emtansine (TDM-1), trastuzumab plus carboplatin, taxanes and pertuzumab (TCHP), trastuzumab plus docetaxel and lapatinib (THL), trastuzumab, taxanes and pertuzumab (THP), ado-trastuzumab emtansine plus pertuzumab (TDM1+P), trastuzumab plus taxanes (TH), trastuzumab plus taxanes and neratinib, taxanes plus pertuzumab (HP), taxanes and neratinib (HN), trastuzumab plus lapatinib (TL), trastuzumab plus pertuzumab (TP) in sequence.

CONCLUSION

Double-targeted therapy in chemotherapy-based regimens was associated with better pCR than single-targeted therapy, and TDM-1+L stood out. For either single-targeted or double-targeted therapies, regimens free of chemotherapy were always worse than those with targeted therapy. Our data support guidelines that recommend combinations of chemotherapies plus targeted therapies in the neoadjuvant setting for early TPBC.

Systematic review and meta-analysis of febrile neutropenia risk with TCH(P) in HER2-positive breast cancer

BACKGROUND

Docetaxel, carboplatin and trastuzumab, with or without pertuzumab (TCH(P)), has become the preferred (neo)adjuvant regimen for HER2-positive breast cancer. However, its associated febrile neutropenia (FN) risk is unclear: pivotal studies reported FN risks < 10%, but in clinical practice, a high FN rate (> 20%) was observed. This systematic review and meta-analysis determine the FN risk associated with TCH(P) and the indication for primary prophylactic granulocyte colony-stimulating factor (PP G-CSF).

METHODS

The MEDLINE, Embase, Web of Science and Cochrane databases were searched for full-text English articles reporting the FN incidence in early breast cancer patients receiving (neo)adjuvant TCH(P). The primary endpoint was the pooled crude FN incidence in patients treated without PP G-CSF using the random effects method. Secondary endpoints were the FN risk with PP G-CSF support, age-related differences in FN and differences in risk with TCH versus TCHP.

RESULTS

Seventeen studies were included in the systematic review. The pooled estimates of FN incidences were 27.6% (95% CI 18.6 to 37.1) in patients who did not receive PP G-CSF (primary meta-analysis, 9 studies, n = 889) versus 5.0% (95% CI 2.6 to 8.0) in patients administered PP G-CSF (secondary meta-analysis, 7 studies, n = 445). Two studies reported non-significant age-related differences in FN. The risk comparison between TCH and TCHP was inconclusive.

CONCLUSIONS

The crude FN risk associated with (neo)adjuvant TCH(P) is over 20%, the upper limit above which the international guidelines unanimously advise PP G-CSF administration. G-CSF prophylaxis effectively reduces FN risk and should become the standard of care with (neo)adjuvant TCH(P).

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.

Exosomal miR-1246 and miR-155 as predictive and prognostic biomarkers for trastuzumab-based therapy resistance in HER2-positive breast cancer

PURPOSE

This study aimed to investigate the predictive and prognostic roles of circulating exosomal miRNAs in breast cancer treated with trastuzumab-based chemotherapy.

METHODS

Circulating exosomal miRNAs from trastuzumab-resistant (n = 4) and -sensitive (n = 4) patients were profiled using miRNA microarray. The predictive and prognostic roles of filtered miRNAs were validated in 107 early-stage and 68 metastatic patients treated with trastuzumab-based chemotherapy through receiver-operating characteristic (ROC) curve analysis, logistic regression and Cox proportional hazards regression analysis, and Kaplan-Meier survival analysis.

RESULTS

MiRNA microarray analysis revealed miR-1246 and miR-155 were the most up-regulated miRs in trastuzumab-resistant HER2-positive breast cancer patients, which were further validated in trastuzumab-resistant patient samples (n = 32) compared with trastuzumab sensitive ones (n = 36). MiR-1246 showed a ROC curve area of 0.750 with 78.1% sensitivity and 75% specificity in discriminating resistant from sensitive patients (p < 0.001), while miR-155 showed a ROC curve area of 0.877 with 68.8% sensitivity and 97.2% specificity (p < 0.001). Predictive factors and multivariate analysis showed that high levels of miR-1246 and miR-155 strongly predicted poor event-free survival (EFS) for early-stage patients, and poor progression-free survival (PFS) for metastatic patients. However, both miRNAs were revealed not to be associated with overall survival (OS). In addition, Kaplan-Meier survival analysis demonstrated that early-stage and metastatic patients with high expression of miR-1246 and miR-155 had poorer EFS or PFS, respectively, than those with decreased expression of both miRs.

CONCLUSIONS

This study demonstrated the valuable roles of circulating exosomal miR-1246 and miR-155 in distinguishing trastuzumab resistant from sensitive patients.

The role of ado-trastuzumab emtansine in current clinical practice

OBJECTIVE

This review reflects the literature from 2019 to 2020 on ado-trastuzumab emtansine's (T-DM1) therapeutic use, clinical controversies, and newest perspectives on use.Data sources: PubMed was used as a database. Search "ado-trastuzumab emtansine" on June 11th, 2020 resulted in 57 publications: 20 clinical trials, two metanalysis, six randomized controlled studies, 13 reviews, and two systematic reviews. Of the 57 publications, 34 were descriptive of the topic in question and were used for this review.Data summary: T-DM1 is now used for patients with HER2 breast cancer who have residual disease post surgery after neoadjuvant chemotherapy (KATHERINE trial). Initial success prompted KRISTINE trial, which investigated whether T-DM1 can be used as a neoadjuvant therapy. While it did have fewer adverse events, T-DM1 was inferior to chemotherapy in treating early breast cancer. Noted shortcomings of the drug were toxicity limited C_max, slow rate of internalization, lack of payload bystander effects, and number of resistance mechanisms. Proposed solutions were pre-treatment with metformin to augment drug internalization by the cell, use of second generation anti-HER2 antibody-drug conjugates to overcome developing resistance, payload swapping to increase bystander effect.

CONCLUSIONS

While T-DM1 has fewer side-effects, it is inferior to chemotherapy in early breast cancer treatment. More research should be done to overcome resistance pathways, identify rate-limiting intracellular processing pathways, improve bystander, and enhance internalization of the drug. Until more research is done, T-DM1 will continue to be used in HER2 positive breast cancer as well as a few other HER2 expressing tumors that fail to respond to neoadjuvant therapy.

T-DM1-induced thrombocytopenia in breast cancer patients: New perspectives

PURPOSE

Human epidermal growth factor receptor 2 (HER2) is overexpressed in 15-20% of patients with breast cancer. HER2 overexpression is the result of a genetic alteration and this marker is associated with poor clinical outcomes. HER2-targeted therapy can significantly improve the prognosis of patients with either early or advanced HER2-positive breast cancer. One such therapy is the antibody drug conjugate (ADC) trastuzumab emtansine (T-DM1), a combination of trastuzumab and the cytotoxic antimicrotubule agent DM1. After T-DM1 binds HER2, DM1 is subsequently released into the cell. T-DM1 is generally well tolerated and has a relatively low incidence of adverse events. However, there are clinical concerns regarding T-DM1-induced high-grade thrombocytopenia.

METHODS

Here, we summarize the incidence of thrombocytopenia from several clinical trials and review experimental studies to explore the causes for T-DM1-induced thrombocytopenia. Progress in several other ADCs targeting HER2-positive breast cancer was also reviewed.

CONCLUSIONS

We conclude that T-DM1 uptake by megakaryocytes occurs through either Fcγ receptor binding or through pinocytosis, and we suggest several methods through which these processes could be interrupted to potentially improve the clinical safety of T-DM1. More generally, we recommend that toxicity should be carefully addressed during the development of ADCs.

Advances in EGFR/HER2-directed clinical research on breast cancer

The discovery of the HER2 molecules has embarked a series of investigations on the efficacy and safety of different types of anti-HER2 therapies for treating breast cancer, with the clinical pathway requiring a more detailed, more precise, and more dynamics therapeutic approaches due to the heterogeneity of the disease. As the "do more" and "do less" approaches are becoming more important to personalize treatment for early HER2-positive breast cancer, recent advances aim at tackling the advanced stage of the disease by using novel therapeutic agents and combination strategies. There are also important points of consideration on prognosis and choice of therapies, including HER2 gene copy number, HER2 heterogeneity, tissue biomarkers, blood-based biomarkers, and HER2 mutation and its treatment. Altogether, these could potentially play a vital role in the journey of HER2-positive breast cancer patient to achieve greater survival benefit and potentially a cure for the disease.