Phase II trial of preoperative paclitaxel, gemcitabine, and trastuzumab combination therapy in HER2 positive stage II/III breast cancer: The Korean Cancer Study Group BR 07-01

Proposing a novel molecular subtyping scheme for predicting distant recurrence-free survival in breast cancer post-neoadjuvant chemotherapy with close correlation to metabolism and senescence

Background

High relapse rates remain a clinical challenge in the management of breast cancer (BC), with distant recurrence being a major driver of patient deterioration. To optimize the surveillance regimen for distant recurrence after neoadjuvant chemotherapy (NAC), we conducted a comprehensive analysis using bioinformatics and machine learning approaches.

Materials and methods

Microarray data were retrieved from the GEO database, and differential expression analysis was performed with the R package 'Limma'. We used the Metascape tool for enrichment analyses, and 'WGCNA' was utilized to establish co-expression networks, selecting the soft threshold power with the 'pickSoftThreshold' algorithm. We integrated ten machine learning algorithms and 101 algorithm combinations to identify key genes associated with distant recurrence in BC. Unsupervised clustering was performed with the R package 'ConsensusCluster Plus'. To further screen the key gene signature of residual cancer burden (RCB), multiple knockdown studies were analyzed with the Genetic Perturbation Similarity Analysis (GPSA) database. Single-cell RNA sequencing (scRNA-seq) analysis was conducted through the Tumour Immune Single-cell Hub (TISCH) database, and the XSum algorithm was used to screen candidate small molecule drugs based on the Connectivity Map (CMAP) database. Molecular docking processes were conducted using Schrodinger software. GMT files containing gene sets associated with metabolism and senescence were obtained from GSEA MutSigDB database. The GSVA score for each gene set across diverse samples was computed using the ssGSEA function implemented in the GSVA package.

Results

Our analysis, which combined Limma, WGCNA, and machine learning approaches, identified 16 RCB-relevant gene signatures influencing distant recurrence-free survival (DRFS) in BC patients following NAC. We then screened GATA3 as the key gene signature of high RCB index using GPSA analysis. A novel molecular subtyping scheme was developed to divide patients into two clusters (C1 and C2) with different distant recurrence risks. This molecular subtyping scheme was found to be closely associated with tumor metabolism and cellular senescence. Patients in cluster C2 had a poorer DRFS than those in cluster C1 (HR: 4.04; 95% CI: 2.60-6.29; log-rank test p < 0.0001). High GATA3 expression, high levels of resting mast cell infiltration, and a high proportion of estrogen receptor (ER)-positive patients contributed to better DRFS in cluster C1. We established a nomogram based on the N stage, RCB class, and molecular subtyping. The ROC curve for 5-year DRFS showed excellent predictive value (AUC=0.91, 95% CI: 0.95-0.86), with a C-index of 0.85 (95% CI: 0.81-0.90). Entinostat was identified as a potential small molecule compound to reverse high RCB after NAC. We also provided a comprehensive review of the EDCs exposures that potentially impact the effectiveness of NAC among BC patients.

Conclusion

This study established a molecular classification scheme associated with tumor metabolism and cancer cell senescence to predict RCB and DRFS in BC patients after NAC. Furthermore, GATA3 was identified and validated as a key gene associated with BC recurrence.

Gemcitabine-Induced Myositis in a Luminal B Breast Cancer patient: A Case Report

Human epidermal growth factor receptor-positive breast cancer is an aggressive cancer which represents approximately a quarter of all breast cancers worldwide. Recent advances have led to the development of targeted therapies, such as trastuzumab (H), which have significantly improved prognosis. Such therapies are currently used alongside other chemotherapeutic agents, such as paclitaxel (P) and gemcitabine (G). The most common side effects of PGH combination therapy include thrombocytopenia and anemias. However, there have been no previous reports of myositis resulting from this combination. We report the case of a 54-year-old metastatic breast cancer patient on PGH therapy who developed muscle weakness. The patient was initially treated with trastuzumab, pertuzumab, and paclitaxel. However, pertuzumab was changed to gemcitabine due to severe diarrhea. After the fourth cycle of PGH, the patient presented with muscle weakness and creatine kinase levels of up to 6755 U/L. Magnetic resonance imaging of the femur and pelvis revealed diffuse bilateral myositis, suggesting a diagnosis of gemcitabine-induced myositis. The patient was placed on intravenous fluids and corticosteroids, which resolved her condition. To our knowledge, this is the first report of gemcitabine-induced myositis in a breast cancer patient. Further studies are needed to determine the underlying mechanisms of gemcitabine-induced myositis and develop preventative measures.

Comparison of two regimens of weekly paclitaxel plus gemcitabine in patients with metastatic breast cancer: propensity score-matched analysis of real-world data

Purpose

Weekly gemcitabine + paclitaxel (wGT) administration is widely applied in real-world clinical practice. The 28-day and 21-day regimens of wGT are the most widely accepted regimens. We evaluated the efficacy and safety of wGT administration in patients with metastatic breast cancer (MBC) and compared the two regimens.

Methods

Patients with human epidermal growth factor receptor 2 (HER-2)-negative MBC who received wGT between October 2013 and October 2016 were identified using an electronic database. The outcome variables included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and safety profile. Propensity score matching was performed to minimize potential confounders.

Results

A total of 140 patients were included. The median PFS and OS was 7.8 [95% confidence interval (CI) = 7.0-8.7] months and 22.5 (95% CI = 18.8-26.1) months, respectively. The toxicity of wGT was manageable. Among the patients, 90 (64.3%) received the 21-day regimen and 50 (35.7%) received the 28-day regimen. A higher number of younger patients and patients receiving later-line therapy received the 28-day regimen. There was no significant difference between the two groups in PFS after propensity score matching, though subgroup analysis showed that patients with early relapse benefited more from the 28-day regimen. The ORR was numerically higher in 28-day regimen (37.8% versus 28.0%, p = 0.310). However, the 21-day regimen was better tolerated than the 28-day regimen.

Conclusion

wGT administration showed efficacy and safety in patients with MBC. The efficacy was comparable between the two regimens after adjustment for confounding factors while the 21-day regimen was better tolerated.

Plain Language Summary

21-day regimen of wGT was well tolerated in patients with metastatic breast cancer Weekly gemcitabine + paclitaxel (wGT) administration is widely applied in real-world clinical practice. The 28-day and 21-day regimens of wGT are the most widely accepted regimens. We evaluated the efficacy and safety of wGT administration in patients with metastatic breast cancer (MBC) and compared the two regimens. Patients with human epidermal growth factor receptor 2 (HER-2)-negative MBC who received wGT between October 2013 and October 2016 were identified using an electronic database. The outcome variables included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and safety profile. Propensity score matching was performed to minimize potential confounders. We found that the efficacy was comparable between the two regimens after adjustment for confounding factors while the 21-day regimen was better tolerated.

Targeting Engineered Nanoparticles for Breast Cancer Therapy

Breast cancer (BC) is the second most common cancer in women globally after lung cancer. Presently, the most important approach for BC treatment consists of surgery, followed by radiotherapy and chemotherapy. The latter therapeutic methods are often unsuccessful in the treatment of BC because of their various side effects and the damage incurred to healthy tissues and organs. Currently, numerous nanoparticles (NPs) have been identified and synthesized to selectively target BC cells without causing any impairments to the adjacent normal tissues or organs. Based on an exploratory study, this comprehensive review aims to provide information on engineered NPs and their payloads as promising tools in the treatment of BC. Therapeutic drugs or natural bioactive compounds generally incorporate engineered NPs of ideal sizes and shapes to enhance their solubility, circulatory half-life, and biodistribution, while reducing their side effects and immunogenicity. Furthermore, ligands such as peptides, antibodies, and nucleic acids on the surface of NPs precisely target BC cells. Studies on the synthesis of engineered NPs and their impact on BC were obtained from PubMed, Science Direct, and Google Scholar. This review provides insights on the importance of engineered NPs and their methodology for validation as a next-generation platform with preventive and therapeutic effects against BC.

Pathologic Complete Response after Neoadjuvant Chemotherapy and Impact on Breast Cancer Recurrence and Survival: A Comprehensive Meta-analysis

PURPOSE

While various studies have highlighted the prognostic significance of pathologic complete response (pCR) after neoadjuvant chemotherapy (NAT), the impact of additional adjuvant therapy after pCR is not known.

EXPERIMENTAL DESIGN

PubMed was searched for studies with NAT for breast cancer and individual patient-level data was extracted for analysis using plot digitizer software. HRs, with 95% probability intervals (PI), measuring the association between pCR and overall survival (OS) or event-free survival (EFS), were estimated using Bayesian piece-wise exponential proportional hazards hierarchical models including pCR as predictor.

RESULTS

Overall, 52 of 3,209 publications met inclusion criteria, totaling 27,895 patients. Patients with a pCR after NAT had significantly better EFS (HR = 0.31; 95% PI, 0.24-0.39), particularly for triple-negative (HR = 0.18; 95% PI, 0.10-0.31) and HER2+ (HR = 0.32; 95% PI, 0.21-0.47) disease. Similarly, pCR after NAT was also associated with improved survival (HR = 0.22; 95% PI, 0.15-0.30). The association of pCR with improved EFS was similar among patients who received subsequent adjuvant chemotherapy (HR = 0.36; 95% PI, 0.19-0.67) and those without adjuvant chemotherapy (HR = 0.36; 95% PI, 0.27-0.54), with no significant difference between the two groups (P = 0.60).

CONCLUSIONS

Achieving pCR following NAT is associated with significantly better EFS and OS, particularly for triple-negative and HER2+ breast cancer. The similar outcomes with or without adjuvant chemotherapy in patients who attain pCR likely reflects tumor biology and systemic clearance of micrometastatic disease, highlighting the potential of escalation/deescalation strategies in the adjuvant setting based on neoadjuvant response.See related commentary by Esserman, p. 2771.

Impact of Molecular Subtype Conversion of Breast Cancers after Neoadjuvant Chemotherapy on Clinical Outcome

PURPOSE

The aim of this study was to examine molecular subtype conversions in patients who underwent neoadjuvant chemotherapy (NAC) and analyze their clinical implications.

MATERIALS AND METHODS

We included consecutive breast cancer patients who received NAC at the National Cancer Center, Korea, between August 2002 and June 2011, and had available data on estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 (HER2) receptor status prior to NAC. Molecular subtypes, hormone receptor (HR) status, and ER and PR Allred scores before and after NAC were compared, and the long-term outcomes were analyzed.

RESULTS

Of 322 patients, 32 (9.9%) achieved a pathologic complete response after NAC. HR+/HER2- tumors tended to convert into triple negative (TN) tumors (10.3%), whereas 34.6% of TN tumors gained HR positivity to become HR+/HER2- tumors. Clinical outcomes of molecular subtype conversion groups were compared against patients who remained as HR+/HER2- throughout. The HR+/HER2- to TN group had significantly poorer recurrence-free survival (RFS) (hazard ratio, 3.54; 95% confidence interval [CI], 1.60 to 7.85) and overall survival (OS) (hazard ratio, 3.73; 95% CI, 1.34 to 10.38). Patients who remained TN throughout had the worst outcomes (for RFS: hazard ratio, 3.70; 95% CI, 1.86 to 7.36; for OS: hazard ratio, 5.85; 95% CI, 2.53 to 13.51), while those who converted from TN to HR+/HER2-showed improved comparable survival outcomes.

CONCLUSION

Molecular subtypes of breast cancers changed frequently after NAC, resulting in different tumor prognostication. Tumor subtyping should be repeated after NAC in patients with breast cancer.

Cardiotoxicity of systemic agents used in breast cancer

Several breast cancer therapies can lead to cardiovascular toxicity: drugs such anthracyclines can cause permanent damage, anti-HER2 agents may cause transitory and reversible cardiac dysfunction and others, such as those used in endocrine therapy, primarily disturb lipid metabolism. Considering the seriousness of these complications, trials are now being conducted to address cardiotoxicity associated with new drugs; however, to fully understand their toxicity profiles, longer follow-up is needed. In this review, we compile the information available about cardiac toxicity related to well-established systemic breast cancer treatments, as well as newer drugs, including antiangiogenics, mTOR inhibitors and novel anti-HER2 agents. We also describe current and next generation cardiac biomarkers and functional tests that can optimize treatment and reduce and prevent the incidence of treatment-related cardiotoxicity.

Clinical usefulness of AJCC response criteria for neoadjuvant chemotherapy in breast cancer

PURPOSE

Recently, the American Joint Committee on Cancer (AJCC) 7th edition proposed new response criteria for neoadjuvant chemotherapy (NAC) in breast cancer. The purpose of this study was to evaluate the clinical usefulness of AJCC response criteria.

METHODS

A total of 398 consecutive stage II or III breast cancer patients who received NAC were enrolled in this study. AJCC response criteria were as follows: (1) complete response (CR)-absence of invasive carcinoma in the breast and node; (2) partial response (PR)-decrease in either or both T or N stage; (3) no response (NR)-no change or increase in either or both T or N stage.

RESULTS

Complete response, PR, and NR by AJCC criteria were 9.8, 59.3, and 30.7 %, respectively. Among the 398 patients, 337 patients were available for both paired pre- and post- breast MRI and chest CT. AJCC response criteria were significantly associated with RECIST criteria (P < 0.001). AJCC response was significantly associated with relapse-free survival (RFS) and overall survival (OS). The 5-year RFS rates were 89.6 % in CR, 74.1 % in PR, and 62.6 % in NR (P = 0.002). The 5-year OS rates were 97.4 % in CR, 88.6 % in PR, and 78.3 % in NR (P = 0.012). When adjusting potential prognostic factors, AJCC response was independently associated with RFS and OS.

CONCLUSIONS

AJCC response criteria for NAC in breast cancer have clinical usefulness in evaluating response of NAC, as well as predicting survival. AJCC response criteria can discriminate among patient subgroups with respect to survival.

HER2-targeted therapy in breast cancer: a systematic review of neoadjuvant trials

Targeting human epidermal growth factor receptor 2 (HER2) during or in sequence with chemotherapy improves overall survival in metastatic and early HER2-overexpressing breast cancer. In this paper we systematically review neoadjuvant clinical trial data in HER2-positive breast cancer and discuss key unanswered clinical questions. All trials of HER2-targeted neoadjuvant therapy were identified through non-date-limited searches of PubMED® and Biosis® and congress abstract book searches from 2000-2011. Eligible trials were prospective, had at least 10 patients and a clear definition of pathological complete response (pCR) rate. A total of 50 trials fulfilled the eligibility criteria; 41 single-arm phase II studies were identified, 37 with trastuzumab and 4 with lapatinib, with significant variability in baseline tumour characteristics and pCR rates (range 12-66.7%). Of 9 randomised phase II/III trials, 4 assessed the addition of trastuzumab to chemotherapy and a further 5 randomised trials assessed different HER2-targeting approaches. Four of these studies assessed dual HER2-targeting approaches, which universally increased pCR at the expense of increased non-cardiac toxicity when lapatinib, but not pertuzumab, was added to trastuzumab. Significant advances have been made in HER2 targeting, resulting in a marked increase in the number of breast cancer patients experiencing tumour pCR. Mature data from randomised neoadjuvant and adjuvant studies are awaited for survival outcomes with combination targeted approaches. Unanswered questions centre on the individualisation of therapy and include; which, if any, chemotherapy backbone should be used, and which patients need dual HER2 blockade?