High risk of recurrence for patients with breast cancer who have human epidermal growth factor receptor 2-positive, node-negative tumors 1 cm or smaller

Multiple metastases of human epidermal growth factor receptor 2‑positive, hormone receptor‑positive, pT1a pN0 breast cancer within 1 year after surgery: A case report

Adjuvant chemotherapy is usually not considered for pT1a pN0 human epidermal growth factor receptor 2 (HER2)-positive breast cancer due to its low recurrence rate. The present report describes a case of pT1a hormone receptor-positive HER2-positive breast cancer with multiple recurrences in the axillary lymph nodes and liver within 1 year after radical surgery. A 58-year-old woman underwent left total mastectomy and sentinel lymph node biopsy for left breast cancer with pathological stage IA (pT1a pN0). The subtype corresponded to luminal B-like breast cancer with a nuclear grade of 3 and a Ki-67 labeling index of 37%. An aromatase inhibitor (letrozole) was planned to be administered for 5 years after surgery, but the patient was diagnosed with multiple liver and axillary lymph node metastases 11 months after surgery. After 1 year of chemotherapy (paclitaxel) in combination with anti-HER2 therapy (pertuzumab and trastuzumab), liver metastases resolved. A complete response of the liver lesion has been maintained 4 years after the anti-HER2 therapy initiation. The present case exhibited two poor prognostic factors: High Ki-67 labeling index and nuclear grade 3. Based on the 'Predict' tool, the present case would be expected to have a cancer-related mortality rate of 6% 10 years after surgery with adjuvant endocrine therapy. Although this value may be controversial for postoperative anti-HER2 therapy, the present case should not be considered to be a low-risk case. When the identification of high-risk pT1a pN0 HER2-positive breast cancer is possible, postoperative anti-HER2 therapy plus chemotherapy would be effective in decreasing the rate of recurrence.

Ferroptosis - a potential feature underlying neratinib-induced colonic epithelial injury

PURPOSE

Neratinib, a small-molecule tyrosine kinase inhibitor (TKI) that irreversibly binds to human epidermal growth factor receptors 1, 2 and 4 (HER1/2/4), is an approved extended adjuvant therapy for patients with HER2-amplified or -overexpressed (HER2-positive) breast cancers. Patients receiving neratinib may experience mild-to-severe symptoms of gut toxicity including abdominal pain and diarrhoea. Despite being a highly prevalent complication in gut health, the biological processes underlying neratinib-induced gut injury, especially in the colon, remains unclear.

METHODS

Real-time quantitative polymerase chain reaction (RT-qPCR) and histology were integrated to study the effect of, and type of cell death induced by neratinib on colonic tissues collected from female Albino Wistar rats dosed with neratinib (50 mg/kg) daily for 28 days. Additionally, previously published bulk RNA-sequencing and CRISPR-screening datasets on human glioblastoma SF268 cell line and glioblastoma T895 xenograft, and mouse TBCP1 breast cancer cell line were leveraged to elucidate potential mechanisms of neratinib-induced cell death.

RESULTS

The severity of colonic epithelial injury, especially degeneration of surface lining colonocytes and infiltration of immune cells, was more pronounced in the distal colon than the proximal colon. Sequencing showed that apoptotic gene signature was enriched in neratinib-treated SF268 cells while ferroptotic gene signature was enriched in neratinib-treated TBCP1 cells and T895 xenograft. However, we found that ferroptosis, but less likely apoptosis, was a potential histopathological feature underlying colonic injury in rats treated with neratinib.

CONCLUSION

Ferroptosis is a potential feature of neratinib-induced colonic injury and that targeting molecular machinery governing neratinib-induced ferroptosis may represent an attractive therapeutic approach to ameliorate symptoms of gut toxicity.

Trastuzumab, a monoclonal anti-HER2 antibody modulates cytotoxicity against cholangiocarcinoma via multiple mechanisms

Cholangiocarcinoma (CCA) is an aggressive and fatal cancer. The prognosis is very poor and no optimal chemotherapy has been established. Human epidermal growth factor receptor 2 (HER2, neu, and erbB2) is highly-expressed in breast cancer and is expressed in many other tumors but poorly expressed in CCA. The anti-HER2 antibody, trastuzumab, has been used for the treatment of HER2-positive breast and gastric cancer. In this study, we examined the surface expression of HER2 on seven Thai liver-fluke-associated CCA cell lines by flow cytometry, and found all of these CCA cells were weakly positive for HER2. MTT assay revealed that trastuzumab directly suppressed the growth of CCA. By using FcR-bearing recombinant Jurkat T-cell-expressing firefly luciferase gene under the control of NFAT response elements, we defined the activities of antibody-dependent cytotoxicity (ADCC) and antibody-dependent cell phagocytosis (ADCP). ADCC was confirmed by using expanded NK cells. ADCP was confirmed by using mouse peritoneal macrophages and human monocyte-derived macrophages as effector cells. Rabbit serum was administered to test the complement-dependent cytotoxicity (CDC) activity of trastuzumab. Finally, we evaluated the efficacy of trastuzumab in in vivo patient-derived cell xenograft and patient-derived xenograft (PDX) models. Our results showed that a distinct population of CCA (liver-fluke-associated CCA) expressed HER2. Trastuzumab demonstrated a potent inhibitory effect on even HER2 weakly positive CCA both in vitro and in vivo via multiple mechanisms. Thus, HER2 is a promising target in anti-CCA therapy, and trastuzumab can be considered a promising antibody immunotherapy agent for the treatment of CCA.

Adjuvant Trastuzumab Emtansine Versus Paclitaxel Plus Trastuzumab for Stage I Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: 5-Year Results and Correlative Analyses From ATEMPT

PURPOSE

Long-term outcomes of patients with stage I human epidermal growth factor receptor 2 (HER2)-positive breast cancer receiving adjuvant trastuzumab emtansine (T-DM1) remain undefined, and prognostic predictors represent an unmet need.

METHODS

In the ATEMPT phase II trial, patients with stage I centrally confirmed HER2-positive breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for 1 year or paclitaxel plus trastuzumab (TH). Coprimary objectives were to compare the incidence of clinically relevant toxicities between arms and to evaluate invasive disease-free survival (iDFS) with T-DM1. Correlative analyses included the HER2DX genomic tool, multiomic evaluations of HER2 heterogeneity, and predictors of thrombocytopenia.

RESULTS

After a median follow-up of 5.8 years, 11 iDFS events were observed in the T-DM1 arm, consistent with a 5-year iDFS of 97.0% (95% CI, 95.2 to 98.7). At 5 years, the recurrence-free interval (RFI) was 98.3% (95% CI, 97.0 to 99.7), the overall survival was 97.8% (95% CI, 96.3 to 99.3), and the breast cancer-specific survival was 99.4% (95% CI, 98.6 to 100). Comparable iDFS was observed with T-DM1 irrespective of tumor size, hormone receptor status, centrally determined HER2 immunohistochemical score, and receipt of T-DM1 for more or less than 6 months. Although ATEMPT was not powered for this end point, the 5-year iDFS in the TH arm was 91.1%. Among patients with sufficient tissue for HER2DX testing (n = 187), 5-year outcomes significantly differed according to HER2DX risk score, with better RFI (98.1% v 81.8%, hazard ratio [HR], 0.10, P = .01) and iDFS (96.3% v 81.8%, HR, 0.20, P = .047) among patients with HER2DX low-risk versus high-risk tumors, respectively.

CONCLUSION

Adjuvant T-DM1 for 1 year leads to outstanding long-term outcomes for patients with stage I HER2-positive breast cancer. A high HER2DX risk score predicted a higher risk of recurrence in ATEMPT.

The survival benefit of adjuvant trastuzumab with or without chemotherapy in the management of small (T1mic, T1a, T1b, T1c), node negative HER2+ breast cancer

There is limited data regarding the added benefit of adjuvant systemic therapy in the management of small, node-negative, HER2+ breast cancer. In a multi-institutional retrospective analysis using the American Society of Clinical Oncology CancerLinQ database, we compared survival outcomes among T1a-c N0 HER2+ patients diagnosed between 2010 to 2021 who received locoregional therapy alone or in combination with adjuvant trastuzumab (+/- chemotherapy). Primary outcomes were invasive disease-free survival (iDFS) and overall survival (OS). Of the 1,184 patients, 436 received locoregional therapy alone. We found a statistically significant improvement in iDFS (HR 0.73, P = 0.003) and OS (HR 0.63, P = 0.023) on univariate analysis with adjuvant trastuzumab with or without chemotherapy which remained statistically significant on multivariate analysis. Three-arm univariate analysis found that iDFS was significantly improved with trastuzumab monotherapy (P = 0.003) and combination therapy (P = 0.027) compared to observation. Subgroup data suggests that T1b/c tumors derive the greatest benefit.

Quality-adjusted life years for HER2-positive, early-stage breast cancer using trastuzumab-containing regimens in the context of cost-effectiveness studies: a systematic review

INTRODUCTION

This study aims to provide a comprehensive assessment of economic and health-related quality of life (HRQoL) outcomes for human epidermal growth factor receptor 2 (HER2)-positive, early-stage breast cancer patients treated with trastuzumab-containing regimens, by focusing on both Incremental Cost-Effectiveness Ratios (ICERs) and quality-adjusted life years (QALYs).

METHODS

A systematic search was conducted across PubMed, Embase, and Scopus databases without language or publication year restrictions. Two independent reviewers screened eligible studies, extracted data, and assessed methodology and reporting quality using the Drummond checklist and Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022), respectively. Costs were converted to US dollars (US$) for 2023 for cross-study comparison.

RESULTS

Twenty-two articles, primarily from high-income countries (HICs), were included, with ICERs ranging from US$13,176/QALY to US$254,510/QALY, falling within country-specific cost-effectiveness thresholds. A notable association was observed between higher QALYs and lower ICERs, indicating a favorable cost-effectiveness and health outcome relationship. EQ-5D was the most utilized instrument for assessing health state utility values, with diverse targeted populations.

CONCLUSIONS

Studies reporting higher QALYs tend to have lower ICERs, indicating a positive relationship between cost-effectiveness and health outcomes. However, challenges such as methodological heterogeneity and transparency in utility valuation persist, underscoring the need for standardized guidelines and collaborative efforts among stakeholders.

REGISTRATION

PROSPERO ID: CRD42021259826.

Trastuzumab deruxtecan in previously treated HER2-positive metastatic or unresectable breast cancer: Real-life data from the temporary use authorization program in France

BACKGROUND

Early access program (formerly cohort Temporary Authorization for Use) was granted for trastuzumab deruxtecan (T-DXd) in France based on DESTINY-Breast01 trial which demonstrated its efficacy and safety in HER2-positive metastatic/unresectable breast cancer after ≥2 anti-HER2-based regimens received at metastatic stage.

METHODS

This multicenter real-world early access program included HER2-positive metastatic/unresectable breast patients pretreated with at least two lines of anti-HER2 regimens who received T-DXd 5.4 mg/kg intravenously in monotherapy every 3 weeks.

RESULTS

Four hundred and fifty-nine patients (median age, 58 years; hormone receptor-positive, 67%; brain metastases, 28.1%) received T-DXd. Before inclusion, 81.7% of patients had radiation therapy and 76.5% had undergone surgery. Median number of prior metastatic treatment lines was four (range, 2-22); 99.8% patients had received trastuzumab, 94.8% trastuzumab emtansine and 79.3% pertuzumab. Follow-up was performed from September 30, 2020 to March 30, 2021; when the early access program stopped, the median duration of T-DXd treatment was 3.4 (range, 0-7.8) months. In 160 patients with available tumor assessment, objective response rate was 56.7% and 12.1% had progression. In 57 patients with available brain tumor assessment, complete or partial intracranial response was reported for 35.7% patients and 5.4% had progression. A total of 17 (3.7%) patients with interstitial lung disease (ILD) was reported with no cases of ILD-related death.

CONCLUSIONS

In this early access program in patients with heavily pretreated HER2-positive metastatic/unresectable breast cancer, T-DXd had antitumor activity with a similar response to that reported in previous clinical studies. T-DXd was well tolerated and no new safety signals were observed.

Real-world clinical outcomes of patients with stage I HER2-positive breast cancer treated with adjuvant paclitaxel and trastuzumab

Up to 20% of breast cancer overexpress HER2 protein, making it a reliable target for antibody-based treatments. In early HER2-positive breast cancer avoiding anthracycline-based chemotherapy is a challenge. Based on the single-arm phase II APT trial results, adjuvant paclitaxel/trastuzumab is an accepted regimen for patients with stage I HER2-positive disease. In our retrospective study of 240 patients, the median tumor size was 12.0 mm (IQR 9 -15), and 204 (85%) had estrogen receptor-positive disease. After a median follow-up of 4.6 years, 3-year real-world disease-free survival, distant DFS, and overall survival were 98.8% (95% confidence interval (CI), 96.2-99.6), 99.2% (95% CI, 96.7-99.8), and 98.3% (95% CI, 96.2-99.6), respectively. In a real-world setting, an adjuvant paclitaxel/trastuzumab regimen was associated with low recurrence rates among women with stage I, HER2-positive breast cancer. Additionally, we reviewed other treatment optimization strategies attempted or ongoing in HER2-positive breast cancer.

Cardiotoxicity in breast cancer treatment: Causes and mitigation

Survivorship issues and treatment related toxicities have considerably increased in breast cancer patients following improved therapeutic options. Cardiotoxicity has been a major treatment related side effects in these patients. Despite this being a well-known entity, the real magnitude of the problem remains an enigma. The amount of research in mitigation of cardiotoxicity or its management in breast cancer survivors is limited and there is an urgent need for finding solutions for the problem. In this article, we are reviewing the agents that cause cardiotoxicity and suggesting a proposal for follow up of breast cancer survivors in an attempt to reduce the magnitude of impact on their quality of life.

The immune checkpoint adenosine 2A receptor is associated with aggressive clinical outcomes and reflects an immunosuppressive tumor microenvironment in human breast cancer

Background

The crosstalk between the immune system and cancer cells has aroused considerable interest over the past decades. To escape immune surveillance cancer cells evolve various strategies orchestrating tumor microenvironment. The discovery of the inhibitory immune checkpoints was a major breakthrough due to their crucial contribution to immune evasion. The A2AR receptor represents one of the most essential pathways within the TME. It is involved in several processes such as hypoxia, tumor progression, and chemoresistance. However, its clinical and immunological significance in human breast cancer remains elusive.

Methods

The mRNA expression and protein analysis were performed by RT-qPCR and immunohistochemistry. The log-rank (Mantel-Cox) test was used to estimate Kaplan-Meier analysis for overall survival. Using large-scale microarray data (METABRIC), digital cytometry was conducted to estimate cell abundance. Analysis was performed using RStudio software (7.8 + 2023.03.0) with EPIC, CIBERSORT, and ImmuneCellAI algorithms. Tumor purity, stromal and immune scores were calculated using the ESTIMATE computational method. Finally, analysis of gene set enrichment (GSEA) and the TISCH2 scRNA-seq database were carried out.

Results

Gene and protein analysis showed that A2AR was overexpressed in breast tumors and was significantly associated with high grade, elevated Ki-67, aggressive molecular and histological subtypes, as well as poor survival. On tumor infiltrating immune cells, A2AR was found to correlate positively with PD-1 and negatively with CTLA-4. On the other hand, our findings disclosed more profuse infiltration of protumoral cells such as M0 and M2 macrophages, Tregs, endothelial and exhausted CD8+ T cells within A2ARhigh tumors. According to the Single-Cell database, A2AR is expressed in malignant, stromal and immune cells. Moreover, it is related to tumor purity, stromal and immune scores. Our results also revealed that CD8+T cells from A2ARhigh patients exhibited an exhausted functional profile. Finally, GSEA analysis highlighted the association of A2AR with biological mechanisms involved in tumor escape and progression.

Conclusion

The present study is the first to elucidate the clinical and immunological relevance of A2AR in breast cancer patients. In light of these findings, A2AR could be deemed a promising therapeutic target to overcome immune evasion prevailing within the TME of breast cancer patients.

Identifying clinicopathological risk factors for regional lymph node metastasis in Chinese patients with T1 breast cancer: a population-based study

Objectives

To analyze clinicopathological risk factors and regular pattern of regional lymph node metastasis (LNM) in Chinese patients with T1 breast cancer and the effect on overall survival (OS) and disease-free survival (DFS).

Materials and methods

Between 1999 and 2020, breast cancer patients meeting inclusion criteria of unilateral, no distant metastatic site, and T1 invasive ductal carcinoma were reviewed. Clinical pathology characteristics were retrieved from medical records. Survival analysis was performed using Kaplan-Meier methods and an adjusted Cox proportional hazards model.

Results

We enrolled 11,407 eligible patients as a discovery cohort to explore risk factors for LNM and 3484 patients with stage T1N0 as a survival analysis cohort to identify the effect of those risk factors on OS and DFS. Compared with patients with N- status, patients with N+ status had a younger age, larger tumor size, higher Ki67 level, higher grade, higher HR+ and HER2+ percentages, and higher luminal B and HER2-positive subtype percentages. Logistic regression indicated that age was a protective factor and tumor size/higher grade/HR+ and HER2+ risk factors for LNM. Compared with limited LNM (N1) patients, extensive LNM (N2/3) patients had larger tumor sizes, higher Ki67 levels, higher grades, higher HR- and HER2+ percentages, and lower luminal A subtype percentages. Logistic regression indicated that HR+ was a protective factor and tumor size/higher grade/HER2+ risk factors for extensive LNM. Kaplan-Meier analysis indicated that grade was a predictor of both OS and DFS; HR was a predictor of OS but not DFS. Multivariate survival analysis using the Cox regression model demonstrated age and Ki67 level to be predictors of OS and grade and HER2 status of DFS in stage T1N0 patients.

Conclusion

In T1 breast cancer patients, there were several differences between N- and N+ patients, limited LNM and extensive LNM patients. Besides, HR+ plays a dual role in regional LNM. In patients without LNM, age and Ki67 level are predictors of OS, and grade and HER2 are predictors of DFS.

A Multi-Centre Randomized Study Comparing Two Standard of Care Chemotherapy Regimens for Lower-Risk HER2-Positive Breast Cancer

BACKGROUND

Neither paclitaxel plus trastuzumab (P-H) nor docetaxel-cyclophosphamide plus trastuzumab (TC-H) have been prospectively compared in HER2-positive early-stage breast cancer (EBC). A randomized trial was performed to assess the feasibility of a larger study.

METHODS

Lower-risk HER2-positive EBC patients were randomized to either P-H or TC-H treatment arms. The co-primary feasibility outcomes were: ≥75% patient acceptability rate, active trial participation of ≥50% of medical oncologists, ≥75% and ≥90% treatment completion, and receipt rate of planned cycles of chemotherapy, respectively.

SECONDARY OUTCOMES

Febrile neutropenia (FN) rate, treatment-related hospitalizations, health-related quality of life (HR-QoL) questionnaires. Analyses were performed by per protocol and intention-to-treat.

RESULTS

Between May 2019 and March 2021, 49 of 52 patients agreed to study participation (94% acceptability rate). Fifteen (65%) of 23 medical oncologists approached patients. Rates of FN were higher (8.3% vs. 0%) in the TC-H vs. P-H arm. Median (IQR) changes in scores from baseline in FACT-Taxane Trial Outcome Index at 24 weeks were -4 (-10, -1) vs. -6.5 (-15, -2) for TC-H and P-H arms, respectively.

CONCLUSIONS

A randomized trial comparing P-H and TC-H was feasible. Expansion to a larger trial would be feasible to explore patient-reported outcomes of these adjuvant HER2 chemotherapy regimens.

Cardioprotective Agents for the Primary Prevention of Trastuzumab-Associated Cardiotoxicity: A Systematic Review and Meta-Analysis

There are significant considerations about the prevention of cardiotoxicity caused by trastuzumab therapy in patients with breast cancer, leading to discontinuation. Recently, randomized controlled trials (RCTs) have evaluated the effects of early commitment of beta-blockers (BBs), angiotensin receptor blockers (ARBs) and angiotensin converting enzyme inhibitors (ACEIs) during trastuzumab chemotherapy in order to prevent the related cardiotoxicity. The present systematic review and meta-analysis of six RCTs included patients who have predominantly non-metastatic, HER2-positive, breast cancer and received trastuzumab as primary or adjuvant therapy. Those patients did not have any obvious cardiac dysfunction or any previous therapy with cardioprotective agent. We evaluated the efficacy of the aforementioned medications for primary prevention of cardiotoxicity, using random effects models. Any preventive treatment did not reduce cardiotoxicity occurrence compared to controls (Odds ratios (OR) = 0.92, 95% CI 0.54-1.56, p = 0.75). Results were similar for ACEIs/ARBs and beta-blockers. Treatment with ACEIs/ARBs led to a slight, but significant, increase in LVEF in patients compared to the placebo group. Only two studies reported less likelihood of discontinuation of trastuzumab treatment. More adequately powered RCTs are needed to determine the efficacy of routine prophylactic therapy.

Pregnancy Associated Invasive Apocrine Carcinoma of the Breast: Case Report from Ethiopia

We present a case report on a case of invasive apocrine carcinoma of breast during pregnancy at a tertiary referral hospital in Ethiopia. The patient's case in this report signifies the challenging clinical situation that the patient, developing fetus and treating physicians have to go through and the need to improve maternal-fetal medicine and oncologic setup and treatment guidelines in Ethiopia. Our case also illustrates the huge disparity between the management of both breast cancer and its occurrence during pregnancy in low-income countries like Ethiopia and developed nations elsewhere. Our case report shows a rare histological finding. The patient has invasive apocrine carcinoma of the breast. To our knowledge, it is the first case to be reported in the country.

Adjuvant paclitaxel and trastuzumab for node-negative, HER2-positive breast cancer: final 10-year analysis of the open-label, single-arm, phase 2 APT trial

BACKGROUND

We aimed to report on long-term outcomes of patients with small, node-negative, HER2-positive breast cancer treated with adjuvant paclitaxel and trastuzumab and to establish potential biomarkers to predict prognosis.

METHODS

In this open-label, single-arm, phase 2 study, patients aged 18 years or older, with small (≤3 cm), node-negative, HER2-positive breast cancer, and an Eastern Cooperative Oncology Group performance status of 0-1, were recruited from 16 institutions in 13 cities in the USA. Eligible patients were given intravenous paclitaxel (80 mg/m²) with intravenous trastuzumab (loading dose of 4 mg/kg, subsequent doses 2 mg/kg) weekly for 12 weeks, followed by trastuzumab (weekly at 2 mg/kg or once every 3 weeks at 6 mg/kg) for 40 weeks to complete a full year of trastuzumab. The primary endpoint was 3-year invasive disease-free survival. Here, we report 10-year survival outcomes, assessed in all participants who received protocol-defined treatment, with exploratory analyses using the HER2DX genomic tool. This study is registered on ClinicalTrials.gov, NCT00542451, and is closed to accrual.

FINDINGS

Between Oct 29, 2007, and Sept 3, 2010, 410 patients were enrolled and 406 were given adjuvant paclitaxel and trastuzumab and included in the analysis. Mean age at enrolment was 55 years (SD 10·5), 405 (99·8%) of 406 patients were female and one (0·2%) was male, 350 (86·2%) were White, 28 (6·9%) were Black or African American, and 272 (67·0%) had hormone receptor-positive disease. After a median follow-up of 10·8 years (IQR 7·1-11·4), among 406 patients included in the analysis population, we observed 31 invasive disease-free survival events, of which six (19·4%) were locoregional ipsilateral recurrences, nine (29·0%) were new contralateral breast cancers, six (19·4%) were distant recurrences, and ten (32·3%) were all-cause deaths. 10-year invasive disease-free survival was 91·3% (95% CI 88·3-94·4), 10-year recurrence-free interval was 96·3% (95% CI 94·3-98·3), 10-year overall survival was 94·3% (95% CI 91·8-96·8), and 10-year breast cancer-specific survival was 98·8% (95% CI 97·6-100). HER2DX risk score as a continuous variable was significantly associated with invasive disease-free survival (hazard ratio [HR] per 10-unit increment 1·24 [95% CI 1·00-1·52]; p=0·047) and recurrence-free interval (1·45 [1·09-1·93]; p=0·011).

INTERPRETATION

Adjuvant paclitaxel and trastuzumab is a reasonable treatment standard for patients with small, node-negative, HER2-positive breast cancer. The HER2DX genomic tool might help to refine the prognosis for this population.

FUNDING

Genentech.

Adjuvant treatment with trastuzumab of patients with HER2-positive, T1a-bN0M0 breast tumors: A systematic review and meta-analysis

The benefit of adjuvant trastuzumab treatment in patients with HER2-positive breast tumors ≤ 10 mm without lymph node involvement (T1abN0) is insufficiently investigated. The aim of this systematic review and meta-analysis was to examine if adjuvant trastuzumab improves the prognosis in these patients. Databases were searched to identify interventional and observational studies evaluating the effect of trastuzumab on breast cancer specific survival (BCSS), disease free survival (DFS), distant recurrence free survival (DRFS), overall survival (OS) or recurrence free survival (RFS). Twelve studies examining the effect of trastuzumab and nine control studies without trastuzumab were identified (n = 6927). Median follow-up was 36-123 months. Significantly improved DFS (Hazard Ratio (HR) 0.14, p < 0.0001) and OS (HR 0.17, p = 0.011) were found for patients receiving trastuzumab and chemotherapy compared to no trastuzumab/chemotherapy based on four and two studies. The prognosis was good even for patients without trastuzumab treatment: 5-year DFS 88.3% and 5-year OS 95.9%.

Systemic Therapy for Early- and Late-Stage, Human Epidermal Growth Factor Receptor-2-Positive Breast Cancer

Systemic therapy for both early-stage and metastatic human epidermal growth factor receptor-2-positive (HER2+) breast cancer has seen significant evolution over the last 20 or more years. Innovative trials leveraging the prognostic and predictive information that neoadjuvant chemotherapy provides has led to preoperative systemic therapy becoming the overwhelmingly favored sequencing in the early-stage setting. However, deintensification of therapy is important to consider for patients with good-risk disease or significant comorbidities. Finally, with the abundance of newly approved agents, drug sequencing in the second-line setting has become an important and individualized decision for patients with metastatic disease.

Adjuvant chemotherapy in patients with ER-negative/HER2-negative, T1abN0 breast cancer: a nationwide study

PURPOSE

The purpose of this study was to examine the effect of chemotherapy on invasive disease-free survival (iDFS) and overall survival (OS) in a nationwide cohort of patients with estrogen receptor (ER)-negative/human epidermal growth factor receptor 2 (HER2)-negative, T1abN0 breast cancer.

METHODS

Patients with ER-negative/HER2-negative, T1abN0 breast cancer registered in the Danish Breast Cancer Group database between 2007 and 2016 were identified. The effect of adjuvant chemotherapy on iDFS and OS was analyzed with Cox proportional hazards analysis.

RESULTS

In total, 296 patients were included in the statistical analyses. Of these, 235 (79.4%) received chemotherapy and 61 patients (20.6%) did not. Patients treated with chemotherapy were significantly younger, had a significantly higher proportion of grade 3 tumors, T1b tumors, and tumors of ductal subtype. With 7.7 years of median follow-up, treatment with chemotherapy was associated with a significant improvement in OS in the adjusted analysis, Hazard Ratio 0.35 (95% Confidence Interval (0.15-0.81), p = 0.02), chemotherapy vs. no chemotherapy. In the unadjusted analyses, patients with both T1a and T1b tumors had significantly improved OS with chemotherapy. At 5 years, OS was 100% vs. 94.4% and 93.8% vs. 81.3% for patients with T1a and T1b tumors, respectively, chemotherapy vs. no chemotherapy. With 4.9 years of median follow-up, iDFS was not significantly improved with chemotherapy.

CONCLUSION

Patients with ER-negative/HER2-negative, T1abN0 breast cancer had significantly improved OS when treated with chemotherapy. This improvement was significant in patients with both T1a and T1b tumors, respectively. The effect was, however, limited in patients with T1a tumors.

Prognostic factors and adjuvant systemic therapy for patients with HER2-positive T1N0 breast cancer: evidence from a real-world study with long-term follow-up

PURPOSE

The optimal adjuvant systemic treatment and potential prognostic factors for patients with T1N0 HER2-positive breast cancer are still unclear. We conducted a real-world study in this relatively low-risk population to identify the clinical-pathological factors of potential prognostic value and to compare the efficacy of different adjuvant strategies.

METHODS

We included patients with HER2-positive T1N0 breast cancer of infiltrating ductal carcinoma (IDC) histology treated at the Cancer Hospital, Chinese Academy of Medical Sciences from April 2010 to April 2017. We performed Cox multivariate analysis to identify the potential prognostic factors for invasive disease-free survival (IDFS). We also compared survival outcomes of (1) patients treated with adjuvant chemotherapy alone, or chemotherapy plus trastuzumab, or observation; (2) patients receiving adjuvant anthracycline-based and non-anthracycline regimens, both combined with trastuzumab. Inverse probability of treatment weighting (IPTW) propensity score was used to reduce selection bias.

RESULTS

Overall, 692 consecutive patients were included, with a median follow-up of 78.0 months for IDFS. Age ≤ 40, T1c, ER + PR + , and adjuvant trastuzumab were identified as independent prognostic factors. For adjuvant treatment, compared with observation and chemotherapy alone, chemotherapy plus trastuzumab could significantly benefit patients (HR = 2.70, P = 0.034; HR = 3.95, P < 0.001). Meanwhile, compared with observation, chemotherapy alone did not significantly benefit patients (HR = 1.37, P = 0.424). For the comparison of anthracycline-based versus non-anthracycline regimens when combined with trastuzumab, patients in both groups had similar IDFS (HR = 1.74, P = 0.242).

CONCLUSIONS

HER2-positive T1N0 IDC patients could benefit from adjuvant chemotherapy plus trastuzumab. Age ≤ 40, T1c, ER + PR + , and adjuvant trastuzumab are independent prognostic factors for this population.

Cardiotoxicity of Biological Therapies in Cancer Patients: An In-depth Review

Cardiotoxicity from chemotherapy regimens has been long reported. However, the understanding of cardiac side effects of biological therapies is rapidly evolving. With cancer patients achieving higher life expectancy due to the use of personalized medicine and novel targeted anticancer agents, the occurrence of cardiotoxicity is becoming more significant. Novel biological therapies include anti-HER2 antibodies, tyrosine kinase inhibitors, bruton kinase inhibitors, antivascular endothelial growth factors, proteasome inhibitors, immunomodulator drugs, and immune checkpoint inhibitors. Potential cardiovascular toxicities linked to these anticancer agents include hypertension, arrhythmias, QT prolongation, myocardial ischemia and infarction, left ventricular dysfunction, congestive heart failure, and thromboembolism. Cardiac biomarkers, electrocardiography, echocardiography and magnetic resonance imaging are common diagnostic modalities used for early detection of these complications and timely intervention. This review discusses the various types of cardiotoxicities caused by novel anticancer biologic agents, their molecular and pathophysiological mechanisms, risk factors, and diagnostic and management strategies that can be used to prevent, minimize, and treat them.

Study of risk factors and marker status in women with breast cancer in Brunei Darussalam

OBJECTIVE

To investigate the associations between breast cancer staging and body mass index (BMI), menopausal status, and family history of breast cancer, as well as to assess the expression of tumor markers in women with breast cancer in Brunei Darussalam.

METHODS

A retrospective cross-sectional study was carried out at The Brunei Cancer Centre. Cases of women with breast cancer between 2000 and 2013 were retrieved from the medical records section and entered into a clinical proforma. These were reviewed and analyzed using appropriate statistical methods.

RESULTS

Overall, the mean age at diagnosis was 53.6 years ± 9.83. The postmenopausal women had a significantly higher risk of being diagnosed with late-onset breast cancer than premenopausal women (P = 0.022). The expressions of PR (P = 0.034), Her2 (P = 0.046), and CatD (P = 0.004) were significantly different in breast cancer staging. Other factors did not have a statistically-significant association with breast cancer staging.

CONCLUSION

While most of the factors studied were not significantly different in breast cancer staging, our findings showed that it is recommended that high-risk women perform regular breast screening after the age of 40 years old. A future study highly appreciates comparing breast cancer risk factors among the Bruneian and Western populations.

Prognosis according to the timing of recurrence in breast cancer

Purpose

Clinically, breast cancer can be divided into 4 subtypes based on the presence of hormone receptors, human epidermal growth factor receptor 2 (HER2), and Ki-67. Because the pattern and time of recurrence vary according to the subtype, we evaluated whether there was a difference in overall survival (OS) among the subtypes according to the time and type of recurrence.

Methods

A total of 2,730 patients who underwent breast cancer surgery were analyzed. Early and late recurrence were defined as recurrence within and after 5 years of diagnosis, respectively. Recurrence type was categorized as locoregional recurrence or systemic recurrence.

Results

Hormone receptor-positive tumors were significantly more frequent in the late recurrence group than in the early recurrence group (estrogen receptor positive, 47.8% [early] vs. 78.7% [late]). However, there was no difference in the rate of HER2 overexpression (HER2+, 38.1% [early] vs.39.0% [late]). In subgroup analysis, early recurrence was a significant prognostic factor for OS in all subtypes. However, late recurrence was a significant prognostic factor for OS only in the luminal B subtype (hazard ratio of 4.30). In addition, the luminal B type had the highest proportion in late recurrence patients (63.2%).

Conclusion

The luminal B subtype had a high rate of late recurrence, and late recurrence was a poor prognostic factor for OS only in this subgroup. Therefore, further targeted treatments for luminal B breast cancer are needed and patients with this subtype require close long-term surveillance.

Diastolic heart failure is a new clinical entity of trastuzumab-induced cardiotoxicity: a case report

Background

Cancer therapy-related cardiac dysfunction (CTRCD) is defined as a decrease in the left ventricular ejection fraction (LVEF) of >10% to a value below the lower limit of normal or relative reduction in global longitudinal strain (GLS) >15% from baseline after cancer treatment. However, the possibility of the development of isolated diastolic dysfunction has never been considered in the clinical presentation of CTRCD.

Case summary

An 81-year-old woman was admitted to our institution presenting with prominent bilateral leg oedema, orthopnoea, and 8 kg of weight gain after administration of the anti-human epidermal growth factor receptor 2 (HER-2) antibody, trastuzumab, for HER-2-positive breast cancer. Transthoracic echocardiography showed a preserved LVEF of 62% without a significant reduction in GLS compared with results obtained before anti-HER-2 targeted therapy. Doppler echocardiography distinctly revealed a newly developed significant left ventricular diastolic dysfunction with evidence of elevated filling pressure. After successful achievement of volume reduction, the patient underwent cardiac catheter examination, revealing an elevated pulmonary artery wedge pressure of 18 mmHg. Subsequently, trastuzumab was discontinued and the patient was treated with diuretics, arteriodilators, and venodilators, until the signs and symptoms of heart failure completely disappeared.

Discussion

In the management of CTRCD, including pretreatment screening, cardiotoxicity monitoring, follow-up after anti-cancer agents, and evaluation of the effectiveness of the therapy, too much emphasis has been paid exclusively to the development of systolic dysfunction; however, perspectives for diastolic dysfunction may be needed. A comprehensive multidisciplinary team approach composed of breast surgeons, oncologists, onco-cardiologists, and echocardiography specialists is required.

Benefit of adjuvant chemotherapy and trastuzumab in patients with HER2-positive, node-negative breast tumors ≤ 10 mm: a nationwide study

PURPOSE

The purpose of this study was to evaluate the effect of chemotherapy and trastuzumab on invasive disease-free survival (iDFS) and overall survival (OS) in patients with human epidermal growth factor receptor 2 (HER2) positive, T1abN0 breast cancer.

METHODS

In the Danish Breast Cancer Group database, patients with HER2-positive, T1abN0 tumors diagnosed between 2007 and 2016 were identified. Cox proportional hazards analysis was performed to analyze the association between adjuvant chemotherapy and trastuzumab and iDFS and OS.

RESULTS

Of 605 patients included in the analyses, 465 patients received chemotherapy and trastuzumab and 140 patients did not. Chemotherapy and trastuzumab did not improve iDFS or OS significantly in adjusted analyses. 5-year iDFS was 92.3% vs. 89.9%, Hazard ratio (HR) 1.01 (p = 0.98), and 5-year OS was 97.4% vs. 94.3%, HR 0.60 (p = 0.15), chemotherapy and trastuzumab vs. no chemotherapy/trastuzumab. In unadjusted analyses, significant treatment benefit on OS was found in patients with T1b tumors. The largest absolute treatment benefits were found in patients with T1b tumors and estrogen receptor (ER) negative tumors, respectively, whereas treatment effects in patients with T1a tumors and ER-positive tumors, respectively, were limited.

CONCLUSION

Adjuvant chemotherapy and trastuzumab did not improve OS or iDFS significantly in patients with HER2-positive, T1abN0 breast cancers in adjusted analyses. In unadjusted analyses, significant OS benefit was found in patients with T1b tumors. The largest absolute benefit was observed in patients with T1b tumors and ER-negative tumors, respectively, whereas the effect was limited in patients with T1a tumors and ER-positive tumors, respectively.

Quantifying the Effects of Combination Trastuzumab and Radiation Therapy in Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer

Background: Trastuzumab induces cell cycle arrest in HER2-overexpressing cells and demonstrates potential in radiosensitizing cancer cells. The purpose of this study is to quantify combination trastuzumab and radiotherapy to determine their synergy. Methods: In vitro, HER2+ cancer cells were treated with trastuzumab, radiation, or their combination, and imaged to evaluate treatment kinetics. In vivo, HER2+ tumor-bearing mice were treated with trastuzumab and radiation, and assessed longitudinally. An additional cohort was treated and sacrificed to quantify CD45, CD31, α-SMA, and hypoxia. Results: The interaction index revealed the additive effects of trastuzumab and radiation in vitro in HER2+ cell lines. Furthermore, the results revealed significant differences in tumor response when treated with radiation (p < 0.001); however, no difference was seen in the combination groups when trastuzumab was added to radiotherapy (p = 0.56). Histology revealed increases in CD45 staining in tumors receiving trastuzumab (p < 0.05), indicating potential increases in immune infiltration. Conclusions: The in vitro results showed the additive effect of combination trastuzumab and radiotherapy. The in vivo results showed the potential to achieve similar efficacy of radiotherapy with a reduced dose when combined with trastuzumab. If trastuzumab and low-dose radiotherapy induce greater tumor kill than a higher dose of radiotherapy, combination therapy can achieve a similar reduction in tumor burden.

Correlation of tumour subtype with long-term outcome in small breast carcinomas: a Swedish population-based retrospective cohort study

Purpose

To investigate if molecular subtype is associated with outcome in stage 1 breast cancer (BC).

Methods

Tissue samples from 445 women with node-negative BC ≤ 15 mm, treated in 1986–2004, were classified into surrogate molecular subtypes [Luminal A-like, Luminal B-like (HER2−), HER2-positive, and triple negative breast cancer (TNBC)]. Information on treatment, recurrences, and survival were gathered from medical records.

Results

Tumour subtype was not associated with overall survival (OS). Luminal B-like (HER2−) and TNBC were associated with higher incidence of distant metastasis at 20 years (Hazard ratio (HR) 2.26; 95% CI 1.08–4.75 and HR 3.24; 95% CI 1.17–9.00, respectively). Luminal B-like (HER2−) and TNBC patients also had worse breast cancer-specific survival (BCSS), although not statistically significant (HR 1.53; 95% CI 0.70–3.33 and HR 1.89; 95% CI 0.60–5.93, respectively). HER2-positive BC was not associated with poor outcome despite no patient receiving HER2-targeted therapy, with most of these tumours being ER+.

Conclusions

Stage 1 TNBC or Luminal B-like (HER2−) tumours behave more aggressively. Women with HER2+/ER+ tumours do not have an increased risk of distant metastasis or death, absent targeted treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-022-06691-4.

Perioperative HER2 targeted treatment in early stage HER2-positive breast cancer

Although human epidermal growth factor receptor 2 (HER2)-positive breast cancer was associated with poor prognosis, it has been changed after the development of trastuzumab. There has been great progress in perioperative HER2-targeting treatment, and investigations of several novel drugs and their combinations are ongoing. Adjuvant trastuzumab with or without pertuzumab for 1 year in combination with concomitant chemotherapy has become a standard treatment in high-risk node-negative tumors or node-positive HER2-positive early breast cancer patients without residual disease or who have not received neoadjuvant treatment. For low-risk HER2-positive early breast cancer patients, adjuvant paclitaxel and 1-year trastuzumab are possible alternatives. For residual disease after neoadjuvant treatment, adjuvant trastuzumab emtansine (T-DM1) for 14 cycles is a standard treatment. Non-anthracycline chemotherapy with dual anti-HER2 targeting of trastuzumab and pertuzumab represents one of the preferred neoadjuvant regimens to achieve higher pathologic complete response (pCR) rates and better clinical outcomes. Further research is needed to develop and validate potential biomarkers to predict pCR, which could help escalate or de-escalate anti-HER2 therapy. Trials incorporating novel agents such as T-DM1, trastuzumab deruxtecan (T-DXd), and immune checkpoint inhibitors and trying to de-escalate treatments in neoadjuvant setting are ongoing. In the future, tailored treatments such as no adjuvant therapy, various HER2-directed therapies alone with chemotherapy, combinations of various HER2-directed therapies and chemotherapy, addition of immune checkpoint inhibitors, and omission of surgery will be individualized in HER2-positive early breast cancer patients.

Adjuvant therapy for HER2 positive pT1a-b pN0 breast cancer: A single center cohort study

Deciding if patients with small (≤1 cm), node-negative, human epidermal growth factor receptor 2 (HER2) positive breast cancer should receive adjuvant systemic therapy remains a challenge. No randomized clinical trials have examined the efficacy of trastuzumab in this setting. This prospective observational study aimed to investigate the choice of adjuvant systemic therapy in clinical practice in China.We prospectively collected data from patients with HER-2 positive breast cancer (less than 1 cm and node negative) patients who underwent breast cancer surgery at Shanxi Provincial People's Hospital Breast Center from January 1, 2017 to December 31, 2019, and retrospectively investigated the association between baseline clinicopathological features and treatment strategy, cardiotoxicity, and disease outcome.Of 168 eligible patients, 102 (60.7%) received adjuvant systemic therapy with trastuzumab (AST+T), 47 (28%) received adjuvant systemic therapy without trastuzumab (AST) and 19 (11.3%) did not receive adjuvant systemic therapy. Multivariate logistic regression analysis demonstrated that age, tumor size and hormone receptor status were significantly associated with treatment choice. Three-year invasive disease-free survival probability was 100%, 97.9% and 89.5% with AST+T, AST, and no therapy, respectively (P < .001).The majority of patients (60.7%) with pT1a-b pN0 HER2 positive breast cancer received adjuvant systemic therapy with trastuzumab, whereas only 11.3% did not receive any adjuvant systemic therapy. Tumor size, age and hormone receptor status influenced treatment choice. The 3-year invasive disease-free survival probability was significantly higher for patients who received adjuvant systemic therapy with trastuzumab compared with those who did not receive adjuvant systemic therapy. Cardiac adverse events were rare.

Practice-Changing Perspectives regarding Systemic Therapy in Early Breast Cancer: Opinions of German Experts regarding the 17th St. Gallen International Consensus Conference

The general topic of this year's 17th St. Gallen (SG) International Consensus Conference on the treatment of patients with early breast cancer (SG-BCC) was "Customizing local and systemic therapies for women with early breast cancer." This topic considers that each treatment decision must also consider the cancer-specific situation of the individual patient. This year, the votes of the SG-BCC were again discussed taking into account the multidisciplinary German S3 Guidelines and the recommendations of the Breast Cancer Working Group of the AGO (Arbeitsgemeinschaft Gynäkologische Onkologie; AGO Mamma). As the international panel of the SG-BCC consists of experts from different countries, the votes do represent an international cross-section of opinions. Therefore, it is useful to discuss the voting results with respect to the German evidence-based treatment guidelines. This publication focuses mainly on systemic treatment.

Prognostic significance of crown-like structures to trastuzumab response in patients with primary invasive HER2 + breast carcinoma

Obesity can initiate, promote, and maintain systemic inflammation via metabolic reprogramming of macrophages that encircle adipocytes, termed crown-like structures (CLS). In breast cancer the presence of CLS has been correlated to high body mass index (BMI), larger mammary adipocyte size and postmenopausal status. However, the prognostic significance of CLS in HER2 + breast cancer is still unknown. We investigated the prognostic significance of CLS in a cohort of 69 trastuzumab-naïve and 117 adjuvant trastuzumab-treated patients with primary HER2 + breast cancer. Immunohistochemistry of tumour blocks was performed for CLS and correlated to clinical outcomes. CLS were more commonly found at the adipose-tumour border (B-CLS) (64.8% of patients). The presence of multiple B-CLS was associated with reduced time to metastatic disease (TMD) in trastuzumab treated patients with BMI ≥ 25 kg/m2 but not those with BMI < 25 kg/m2. Phenotypic analysis showed the presence of CD32B + B-CLS was strongly correlated to BMI ≥ 25 kg/m2 and reduced TMD in trastuzumab treated patients. Multivariable analysis suggested that CD32B + B-CLS positive tumours are associated with shorter TMD in trastuzumab-treated patients (HR 4.2 [95%CI, (1.01-17.4). This study indicates adipose-tumour border crown-like structures that are CD32B + potentially represent a biomarker for improved personalisation of treatment in HER2-overexpressed breast cancer patients.

Treatment of small (T1mic, T1a, and T1b) node-negative HER2+ breast cancer - a review of current evidence for and against the use of anti-HER2 treatment regimens

INTRODUCTION

Since the advent of anti-HER2 therapies, evidence surrounding adjuvant treatment of small (T1mic, T1a, and T1b), node-negative, HER2-positive breast cancer (HER2+BC) has remained limited. Practices vary widely between institutions with little known regarding the added benefit of systemic therapy, including cytotoxic chemotherapy and HER2-directed treatments. Our group has set out to perform an extensive review of available literature on this topic.

AREAS COVERED

In this review, we examined HER2 biology, anti-HER therapies, outcome definitions, and available prospective and retrospective data surrounding the use of adjuvant therapy in those with small, node-negative, HER2+BC. For outcomes, we primarily explored breast cancer-specific survival (BCSS), invasive disease-free survival (iDFS), and overall survival (OS). We also investigated the incidence of adverse events with a particular focus on symptomatic and asymptomatic declines in left ventricular ejection fraction.

EXPERT OPINION

Retrospective data will likely be the main driver for future treatment decisions. Given what we know, high risk T1b and T1c subgroups derive measurable added benefit from HER2-guided combination therapies but it's not clear whether these benefits outweigh known risks associated with this combination therapy. For tumors ≤0.5cm (T1mic and T1a), treatment remains highly controversial with limited evidence available through retrospective analysis that suggest over-treatment may be occurring.

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

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

Androgen receptor expression and its prognostic value in T1N0 luminal/HER2- breast cancer

Purpose: The authors aimed to evaluate the prognostic and predictive value of androgen receptor (AR) expression in patients with luminal/human EGFR2 negative (HER2-) T1N0 breast cancer. Methods: The cohort in this retrospective study comprised 471 patients with luminal/HER2- T1N0 breast cancer who had undergone surgery between 2013 and 2017 in the authors' center. Results: Androgen receptor (AR)+ tumors were associated with favorable characteristics. AR+ patients had better 5-year recurrence-free survival rates and the risk of recurrence was greater for AR- than for AR+ patients. AR- status predicted the failure of adjuvant endocrine therapy with aromatase inhibitors and of adjuvant chemotherapy with docetaxel plus cyclophosphamide. Conclusion: AR+ expression is significantly related to a better prognosis. AR expression may be an additional biomarker for both endocrine and chemotherapy responsiveness.

Cardiac outcomes of subjects on adjuvant trastuzumab emtansine vs paclitaxel in combination with trastuzumab for stage I HER2-positive breast cancer (ATEMPT) study (TBCRC033): a randomized controlled trial

The excellent outcomes seen in patients treated with adjuvant trastuzumab emtansine (T-DM1) in the ATEMPT trial and the favorable toxicity profile associated with this agent make T-DM1 a potential therapeutic option for select patients with stage I HER2-positive breast cancer. Moreover, T-DM1 is an established adjuvant treatment for patients with HER2-positive breast cancer with the residual invasive disease after neoadjuvant therapy. Given that cardiotoxicity is the most significant adverse event of trastuzumab, which is a main molecular component of T-DM1, we conducted a sub-analysis of the ATEMPT trial to determine the cardiac safety of adjuvant T-DM1. In this analysis, the incidence of grade 3–4 left ventricular systolic dysfunction (LVSD) in T-DM1 or trastuzumab plus paclitaxel arms were respectively 0.8 and 1.8%. In addition, three (0.8%) patients in the T-DM1 arm and six (5.3%) patients in the adjuvant paclitaxel with trastuzumab (TH) arm experienced a significant asymptomatic left ventricular ejection fraction (LVEF) decline that per-protocol required holding T-DM1 or trastuzumab. All patients with available follow-up data experienced full resolution of cardiac symptoms and LVEF normalization. Furthermore, we performed an exploratory analysis to assess the relationship between age, baseline LVEF, and body mass index with cardiac outcomes. No significant association between these baseline characteristics and the incidence of significant asymptomatic LVEF decline or symptomatic LVSD was identified. The low incidence of significant cardiac adverse events in this population during therapy with adjuvant T-DM1 suggests that studies on the cost-effectiveness of cardiac monitoring during adjuvant therapy using anthracycline-free regimens are needed.

Clinical Trial Registration: ClinicalTrials.gov, NCT01853748

Impacts of clinicopathological factors on efficacy of trastuzumab deruxtecan in patients with HER2-positive metastatic breast cancer

BACKGROUND

The previous second-line treatment for HER2-positive metastatic breast cancer were ado-trastuzumab emtansine (T-DM1); however, its activity is decreased in tumors with heterogenous, reduced, or loss of HER2 expression. Trastuzumab deruxtecan (T-DXd) has recently been developed as a novel antibody-drug conjugate to overcome resistance to T-DM1. However, clinical evidence on its ability to overcome this resistance is limited.

MATERIALS AND METHODS

We retrospectively analyzed data for patients with HER2-positive metastatic breast cancer who received T-DXd at our institution from April 2020 to March 2021. We evaluated the associations between clinicopathological and molecular biomarkers and the efficacy of T-DXd.

RESULTS

Twenty-two patients were enrolled in this study. The median progression-free survival (PFS) was 9.7 months (95% confidence interval [CI], 7.0-not reached [NR]), and the objective response rate (ORR) was 61.9%. The ORR and PFS were comparable between patients with HER2 immunohistochemistry scores of 3+ and 2+/1+ at initial diagnosis (ORR: 50.0% vs. 72.7%, p = 0.39; median PFS, 9.7 months [95%CI, 2.6-NR] vs. 8.3 months [95%CI, 7.1-NR]; hazard ratio, 1.86 [95%CI, 0.53-6.57], p = 0.34). Two patients with heterogenous HER2 expression had a partial response or long stable disease (≥6 months). Three of four patients with re-biopsy samples after anti-HER2 targeted therapy and with latest HER2 immunohistochemistry scores of 1+ experienced partial responses (75.0%) to T-DXd, but none had responded to prior T-DM1.

CONCLUSIONS

T-DXd demonstrated favorable activity in clinical practice. Moreover, T-DXd showed meaningful benefit in patients with heterogeneity, reduction, or loss of HER2 expression.

The Research Progress of Trastuzumab-Induced Cardiotoxicity in HER-2-Positive Breast Cancer Treatment

In recent years, the incidence of breast cancer has been increasing on an annual basis. Human epidermal growth factor receptor-2 (HER-2) is overexpressed in 15-20% human breast cancers, which is associated with poor prognosis and a high recurrence rate. Trastuzumab is the first humanized monoclonal antibody against HER-2. The most significant adverse effect of trastuzumab is cardiotoxicity, which has become an important factor in limiting the safe use of the drug. Unfortunately, the mechanism causing this cardiotoxicity is still not completely understood, and the use of preventive interventions remains controversial. This article focuses on trastuzumab-induced cardiotoxicity, reviewing the clinical application, potential cardiotoxicity, mechanism and discussing the potential interventions through summarizing related researches over the past tens of years.

Efficacy of adjuvant trastuzumab in women with HER2-positive T1a or bN0M0 breast cancer: a population-based cohort study

Adjuvant trastuzumab has been associated with superior survival in women with ≥ T1c or node-positive HER2-positive early-stage breast cancer; however, there is a lack of phase III trials in women with T1a/bN0 disease. Our study aimed to assess the outcomes of women with HER2-positive T1a/bN0 breast cancer who received adjuvant trastuzumab in Saskatchewan, Canada. We evaluated all women diagnosed with HER2-positive T1a/bN0 breast cancer in Saskatchewan between 2008 and 2017. We performed Cox proportional multivariable analysis to determine factors correlated with survival. In addition, inverse probability treatment weighting (IPTW) using propensity score was performed to assess benefit of adjuvant trastuzumab. Ninety-one eligible women with a median age of 61 years (range 30–89) were identified. Thirty-nine (43%) women received adjuvant trastuzumab. Women who received trastuzumab were younger and had a higher rate of T1b disease. Overall, 3% of women who received trastuzumab compared to 12% of women who did not receive trastuzumab developed breast cancer recurrence (p = 0.23). Five-year disease-free survival (DFS) of women who received adjuvant trastuzumab was 94.8% compared to 82.7% of women who did not receive trastuzumab (p = 0.22). Five-year overall survival was 100% of women who received trastuzumab compared to 90.4% of women who did not receive adjuvant trastuzumab (p = 0.038). In the multivariable analysis, grade III tumors were correlated with inferior DFS (hazard ratio [HR] 5.5, 95% CI [1.7–17.7]). The propensity score using the inverse probability of treatment weighting showed that lack of adjuvant trastuzumab was correlated inferior DFS, with an HR of 4 (95% CI 1.05–15.5). Women with HER2-positive T1a/bN0 breast cancer had overall low recurrence of breast cancer. However, the results of this exploratory analysis indicate that women who received adjuvant trastuzumab had better survival.

Ribosomal Protein S6: A Potential Therapeutic Target against Cancer?

Ribosomal protein S6 (RPS6) is a component of the 40S small ribosomal subunit and participates in the control of mRNA translation. Additionally, phospho (p)-RPS6 has been recognized as a surrogate marker for the activated PI3K/AKT/mTORC1 pathway, which occurs in many cancer types. However, downstream mechanisms regulated by RPS6 or p-RPS remains elusive, and the therapeutic implication of RPS6 is underappreciated despite an approximately half a century history of research on this protein. In addition, substantial evidence from RPS6 knockdown experiments suggests the potential role of RPS6 in maintaining cancer cell proliferation. This motivates us to investigate the current knowledge of RPS6 functions in cancer. In this review article, we reviewed the current information about the transcriptional regulation, upstream regulators, and extra-ribosomal roles of RPS6, with a focus on its involvement in cancer. We also discussed the therapeutic potential of RPS6 in cancer.

Emerging Role of PARP Inhibitors in Metastatic Triple Negative Breast Cancer. Current Scenario and Future Perspectives

Triple negative tumors represent 15% of breast cancer and are characterized by the lack of estrogen receptors, progesterone receptor, and HER2 amplification or overexpression. Approximately 25% of patients diagnosed with triple negative breast cancer carry a germline BRCA1 or BRCA2 mutation. They have an aggressive biology, and chemotherapy has been the mainstay of treatment for a long time. Despite intensive therapies, prognosis is still poor, and many patients will eventually relapse or die due to cancer. Therefore, novel targeted agents that can increase the treatment options for this disease are urgently needed. Recently, a new class of molecules has emerged as a standard of care for patients with triple negative breast cancer and germline BRCA1 or BRCA2 mutation: poly (ADP-ribose) (PARP) inhibitors. In the first part of the review, we summarize and discuss evidence supporting the use of PARP inhibitors. Currently, two PARP inhibitors have been approved for triple negative metastatic breast cancer-olaparib and talazoparib-based on two phase III trials, which showed a progression-free survival benefit when compared to chemotherapy. Safety profile was manageable with supportive therapies and dose reductions/interruptions. In addition, other PARP inhibitors are currently under investigation, such as talazoparib, rucaparib, and veliparib. Subsequently, we will discuss the potential role of PARP inhibitors in the future. Clinical research areas are investigating PARP inhibitors in combination with other agents and are including patients without germline BRCA mutations: ongoing phase II/III studies are combining PARP inhibitors with immunotherapy, while phases I and II trials are combining PARP inhibitors with other targeted agents such as ATM and PIK3CA inhibitors. Moreover, several clinical trials are enrolling patients with somatic BRCA mutation or patients carrying mutations in genes, other than BRCA1/2, involved in the homologous recombination repair pathway (e.g., CHECK2, PALB2, RAD51, etc.).

Immune cell profiles of metastatic HER2-positive breast cancer patients according to the sites of metastasis

PURPOSE

Recent works have characterized that metastatic site can affect the tumour immune profiles and efficiency of cancer immunotherapies. The prognosis of HER2-positive breast cancer is associated with the characteristics of the tumour immune microenvironment, with immunological cells playing a central role in efficiency of HER2-targeted antibodies. Here we investigated the prognostic significance of different metastatic sites and their correlation to tumour immune profiles in HER2-positive breast cancer treated with trastuzumab.

METHODS

We collected all (n = 54) HER2-positive metastatic breast cancer patients treated with trastuzumab containing regimens at Oulu University Hospital 2009-2014. Pathological and clinical data were collected from electronic patient records. The tumour immune profiles were analysed from pre-treatment primary tumours using well-characterized immunological markers with computer-assisted immune cell counting.

RESULTS

Of the metastatic sites, only liver metastases were associated with poor prognosis (hazard ratio 1.809, 95% confidence interval 1.004-3.262), especially when presented as the primary site of metastases. Of the other sites, pulmonary metastases characterized a patient profile with trend to improved survival. Of the studied tumour immunological markers, patients with liver metastases had low densities of CD3⁺ T cells (p = 0.030) and M1-like macrophages in their primary tumours (p = 0.025). Of the other studied markers and sites, patients with pulmonary metastases had low STAB1⁺-immunosuppressive macrophage density in their primary tumours.

CONCLUSION

Our results suggest that the site of metastasis is associated with prognosis in HER2-positive breast cancer, highlighted by the poor prognosis of liver metastases. Furthermore, liver metastases were associated with adverse tumour immune cell profiles.

Adjuvant treatment with paclitaxel plus trastuzumab for node-negative breast cancer: real-life experience

Background: In node-negative HER2-overexpressed breast cancers, adjuvant paclitaxel plus trastuzumab treatment is a successful de-escalation approach with excellent survival outcomes. Methods: All patients with HER2+ breast cancer treated in our centers were retrospectively reviewed. Results: We analyzed 173 patients who were treated with adjuvant paclitaxel plus trastuzumab. The mean tumor size was 2.2 cm. There were eight invasive disease events or death: four distant recurrences (2.3%), three locoregional recurrences (1.7%) and one death without documented recurrence after a 52 month follow-up. The 3-year disease-free survival and recurrence-free interval rate was 96.6%. Conclusion: This real-life experience with adjuvant paclitaxel plus trastuzumab demonstrated few distant recurrences and is compatible with the APT trial findings.

Targeted Agents for HER2-Positive Breast Cancer: Optimal Use in Older Patients

The human epidermal growth factor-2 (HER2) gene is overexpressed in 15-20 % of all breast cancers. HER2 overexpression is a predictive factor in breast cancer and is associated with high rates of disease recurrence and death in the absence of adjuvant systemic therapy. With the advent of HER2-directed therapies, there has been a significant improvement in the outcome of HER2-positive (HER2+) breast cancer in all clinical settings. Patients aged > 65 years remain under-represented in most clinical trials. Existing literature suggests that older patients with HER2+ disease derive a similar benefit from anti-HER2 therapies as do their younger counterparts, in both adjuvant and metastatic settings. Cardiotoxicity from HER2-directed therapy is a major concern with older patients, especially in the setting of pre-existing co-morbidities. Older patients need a geriatric assessment before beginning any systemic therapy, to identify patients predisposed to developing toxicity and to plan therapy. Many onco-geriatric tools have been developed to further identify frail patients. In this article, we discuss the most up-to-date clinical data on existing therapies for HER2+ breast cancer in adjuvant, neoadjuvant, and metastatic settings, and their application in older patients. We attempt to highlight clinical benefits and toxicities in this group that may aid clinicians in therapeutic decision making.

Trastuzumab for early-stage, HER2-positive breast cancer: a meta-analysis of 13 864 women in seven randomised trials

BACKGROUND

Trastuzumab targets the extracellular domain of the HER2 protein. Adding trastuzumab to chemotherapy for patients with early-stage, HER2-positive breast cancer reduces the risk of recurrence and death, but is associated with cardiac toxicity. We investigated the long-term benefits and risks of adjuvant trastuzumab on breast cancer recurrence and cause-specific mortality.

METHODS

We did a collaborative meta-analysis of individual patient data from randomised trials assessing chemotherapy plus trastuzumab versus the same chemotherapy alone. Randomised trials that enrolled women with node-negative or node-positive, operable breast cancer were included. We collected individual patient-level data on baseline characteristics, dates and sites of first distant breast cancer recurrence and any previous local recurrence or second primary cancer, and the date and underlying cause of death. Primary outcomes were breast cancer recurrence, breast cancer mortality, death without recurrence, and all-cause mortality. Standard intention-to-treat log-rank analyses, stratified by age, nodal status, oestrogen receptor (ER) status, and trial yielded first-event rate ratios (RRs).

FINDINGS

Seven randomised trials met the inclusion criteria, and included 13 864 patients enrolled between February, 2000, and December, 2005. Mean scheduled treatment duration was 14·4 months and median follow-up was 10·7 years (IQR 9·5 to 11·9). The risks of breast cancer recurrence (RR 0·66, 95% CI 0·62 to 0·71; p<0·0001) and death from breast cancer (0·67, 0·61 to 0·73; p<0·0001) were lower with trastuzumab plus chemotherapy than with chemotherapy alone. Absolute 10-year recurrence risk was reduced by 9·0% (95% CI 7·4 to 10·7; p<0·0001) and 10-year breast cancer mortality was reduced by 6·4% (4·9 to 7·8; p<0·0001), with a 6·5% reduction (5·0 to 8·0; p<0·0001) in all-cause mortality, and no increase in death without recurrence (0·4%, -0·3 to 1·1; p=0·35). The proportional reduction in recurrence was largest in years 0-1 after randomisation (0·53, 99% CI 0·46 to 0·61), with benefits persisting through years 2-4 (0·73, 0·62 to 0·85) and 5-9 (0·80, 0·64 to 1·01), and little follow-up beyond year 10. Proportional recurrence reductions were similar irrespective of recorded patient and tumour characteristics, including ER status. The more high risk the tumour, the larger the absolute reductions in 5-year recurrence (eg, 5·7% [95% CI 3·1 to 8·3], 6·8% [4·7 to 9·0], and 10·7% [7·7 to 13·6] in N0, N1-3, and N4+ disease).

INTERPRETATION

Adding trastuzumab to chemotherapy for early-stage, HER2-positive breast cancer reduces recurrence of, and mortality from, breast cancer by a third, with worthwhile proportional reductions irrespective of recorded patient and tumour characteristics.

FUNDING

Cancer Research UK, UK Medical Research Council.

α-Methylacyl-CoA racemase: a useful immunohistochemical marker of breast carcinoma with apocrine differentiation

Carcinoma with apocrine differentiation is an androgen receptor (AR)-positive subset of triple-negative breast carcinomas. In addition to carcinoma with apocrine differentiation, other AR-positive triple-negative breast carcinomas occur, albeit less frequently. We found that α-methylacyl-CoA racemase (AMACR), also known as P504S, is overexpressed in carcinoma with apocrine differentiation and non-neoplastic apocrine metaplasia. We aimed to evaluate AMACR as a possible marker of carcinoma with apocrine differentiation. We immunohistochemically examined the expression of AMACR in carcinoma with apocrine differentiation and nonapocrine carcinomas and compared it with that of gross cystic disease fluid protein-15 (GCDFP-15). In total, 212 breast carcinomas were evaluated: 39 carcinomas with apocrine differentiation, 28 ductal carcinomas in situ with apocrine morphology (ADCIS), and 145 nonapocrine breast carcinomas. AMACR was expressed in 38 of 39 (97.4%) carcinomas with apocrine differentiation and in 27 of 28 (96.4%) ADCIS, consistent with the expression of GCDFP-15. However, in nonapocrine carcinomas, AMACR expression was observed in 32 of 145 (22.0%) lesions, whereas GCDFP-15 expression was observed in 91 of 145 (62.7%) lesions. For carcinoma with apocrine differentiation, AMACR was as sensitive as GCDFP-15 (both 97.1%) but more specific (77.9% versus 37.2%). In selected cases, AMACR messenger RNA (mRNA) levels were quantitatively determined relative to that of TATA-binding protein mRNA, and they comprised 5.23, 1.33, and 0.60 for carcinomas with apocrine differentiation, nonapocrine carcinomas, and normal breast tissue, respectively. CONCLUSION: Our findings demonstrate that AMACR expression may be used for differentiating carcinoma with apocrine differentiation from nonapocrine carcinomas and indicate that AMACR is a more sensitive carcinoma with apocrine differentiation marker than GCDFP-15.

Does preoperative MRI accurately stratify early-stage HER2 + breast cancer patients to upfront surgery vs neoadjuvant chemotherapy?

PURPOSE

HER2 +- amplified breast cancer patients derive benefit from treatment with anti-HER2-targeted therapy. Though adjuvant treatment is based on final pathology, decisions regarding neoadjuvant chemotherapy are made in the preoperative setting with imaging playing a key role in staging. We examined the accuracy of pre-operative imaging in determining pathological tumor size  (pT) in patients undergoing upfront surgery.

METHODS

Early (cT1-T2N0) HER2 + breast cancer patients who underwent upfront surgery between 2015 and 2016 were identified from a prospective institutional database. We compared data for both clinical and final pathologic stage. Only those who underwent magnetic resonance imaging (MRI), mammography, and ultrasound in the preoperative setting were included in the analysis. Adjuvant treatment regimens were reviewed.

RESULTS

We identified 87 cT1-2N0 patients with invasive HER2 + breast cancer who underwent upfront surgery. Median age was 52 years (IQR 43, 58) and median tumor size was 1.1 cm (IQR 0.5, 1.6). Fifteen patients (17%) were upstaged to stage II/III based on final pathology. Thirty-seven patients were T1cN0 on final pathology; 8 were cT1a-bN0 preop and 12 had pT overestimated by MRI by an average of 1.5 cm (> 0.5-1.5 cm). Compared to both mammography and MRI, the imaging modality most predictive of pT was ultrasound (p = 0.000072 ultrasound vs mammography and 0.000042 ultrasound vs MRI).

CONCLUSION

For small HER2 + cN0 tumors undergoing upfront surgery, ultrasound was the imaging modality most predictive of pT. MRI overestimated tumor size in approximately 40% of patients. MRI may not accurately discriminate low-volume tumor burden in the breast and carries the potential of overtreatment in the upfront setting.

Real-world effectiveness of post-trastuzumab emtansine treatment in patients with HER2-positive, unresectable and/or metastatic breast cancer: a retrospective observational study (KBCSG-TR 1917)

BACKGROUND

Trastuzumab emtansine (T-DM1) is a second-line standard therapy for patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. Evidence regarding post-T-DM1 treatments is currently lacking. We evaluated the effectiveness of post-T-DM1 drug therapy in patients with HER2-positive, unresectable and/or metastatic breast cancer.

METHODS

In this multicenter, retrospective, observational study, real-world clinical data of female patients with HER2-positive breast cancer who had a history of T-DM1 treatment were consecutively collected from five sites in Japan. We investigated the effectiveness of post-T-DM1 therapy by evaluating the real-world progression-free survival (rwPFS), time to treatment failure (TTF), overall survival (OS), objective response rate (ORR), and clinical benefit rate (CBR). Tumor response was assessed by investigators according to Response Evaluation Criteria in Solid Tumors (RECIST version 1.1) guidelines. Subgroup and exploratory analyses according to background factors were also undertaken.

RESULTS

Of the 205 patients who received T-DM1 treatment between 1 January 2014 and 31 December 2018, 128 were included in this study. Among the 128 patients analyzed, 105 (82%) patients received anti-HER2 therapy and 23 (18%) patients received regimens without anti-HER2 therapy. Median (95% confidence interval [CI]) rwPFS, TTF, and OS were 5.7 (4.8-6.9) months, 5.6 (4.6-6.4) months, and 22.8 (18.2-32.4) months, respectively. CBR and ORR (95% CI) were 48% (38.8-56.7) and 23% (15.1-31.4), respectively. Cox-regression analysis showed that an ECOG PS score of 0, a HER2 immunohistochemistry score of 3+, recurrent type, ≥12 month duration of T-DM1 therapy, and anti-HER2 therapy were independent variables for rwPFS. An exploratory subgroup analysis of regimens after T-DM1 showed that those with anti-HER2 therapy had a median rwPFS of 6.3 and those without anti-HER2 therapy had a median rwPFS of 4.8 months.

CONCLUSIONS

In the real-world setting in Japan, several post-T-DM1 regimens for patients with unresectable and/or metastatic HER2-positive breast cancer, including continuation of anti-HER2 therapy, showed some effectiveness; however, this effectiveness was insufficient. Novel therapeutic options are still needed for further improvement of PFS and OS in later treatment settings.

TRIAL REGISTRATION

UMIN000038296 ; registered on 15 October 2019.

De-escalation of Systemic Therapy for Early-Stage, Node-Negative Her2+ and Triple-Negative Breast Cancer

Purpose of Review

This review summarizes the most recent data on the management of small, node-negative Her2+ and triple-negative breast cancer.

Recent Findings

Both Her2+ and triple-negative breast cancers are characterized by high rates of recurrence and worse survival outcomes compared to hormone-positive cancers. De-escalation of systemic therapy in early-stage breast cancer is a recent national trend in clinical research. Recent prospective trials support the scaling back of cytotoxic agents and maximization of targeted therapy regimens. Similarly, large retrospective studies on small, node-negative triple-negative breast cancer report the omission of chemotherapy in women with T1a,N0 triple-negative cancers with favorable short term outcomes.

Summary

De-escalation of systemic therapy for Her2+ breast cancer is effective in the management of early-stage, node-negative disease. Future prospective studies on the omission of systemic therapy for triple-negative breast cancer are required to safely adopt into consensus guidelines.