Estimating the magnitude of trastuzumab effects within patient subgroups in the HERA trial

Effects of hormone receptor status on patient clinic and survival in HER2 positive breast cancer

BACKGROUND

In the current study, the effect of hormone receptor (HR) status on clinical and survival in early-stage human epidermal growth factor receptor 2 (HER2)-positive breast cancer was investigated.

METHODS

Two hundred ninety-one patients with HER2- positive were examined in two categories as HR-positive and HR-negative.

RESULTS

Of these, 197 (68%) were HR-positive and 94 (32%) were HR-negative with a mean follow-up period of 68 ± 2.7 months. The groups were found to be similar in terms of age, menopausal status, comorbidity, pathologic type, stage, T stage, N stage, lymphovascular invasion, presence and percentage of intraductal component, multicentricity/focality and extracapsular invasion. Family history (P = 0.038), stage 2 tumor rate (P < 0.001), and perineural invasion (P = 0.005) were significantly higher in the HR-positive group. In the HR-negative group, mean Ki-67 value (P = 0.014), stage 3 tumor rate (P < 0.001), tumor necrosis (P = 0.004) and strong (3+) HER2 staining on immunohistochemical staining (P = 0.003) were higher. The incidence of relapse and metastasis, and the localization of metastasis were similar in both patient groups. The rate of locoregional relapse during the first 2 years was higher in the HR-negative patients than in the HR-positive patients (P = 0.023). Overall survival (OS) and disease-free survival (DFS) did not differ between the groups in univariate analysis. However, HR status was determined as an independent prognostic factor (HR: 2.11, 95% CI: 1.17-3.79; P = 0.012) for OS was not found to be significant for DFS in multivariate analysis.

CONCLUSION

Both clinicopathologic features and OS outcomes of HR-negative patients were worse than those of HR-positive patients.

Current Management and Future Perspectives in Metastatic HER2-Positive Breast Cancer

OBJECTIVE

Metastatic HER2-positive breast cancer remains a significant clinical challenge with a poor prognosis. The introduction of anti-HER2 therapies has significantly improved survival in early and advanced stages. However, patients with metastatic HER2-positive breast cancer eventually experience progression due to de novo or acquired resistance. This review article comprehensively analyzes the current management of metastatic HER2-positive breast cancer, addressing the complexities in determining the optimal HER2-targeted therapy sequence.

DATA SOURCES

Discussion of selected peer-reviewed articles and expert opinion.

CONCLUSIONS

We explore the actual standard of care and the emerging therapeutic options that hold promise for further improving patient care and survival in this aggressive breast cancer subtype. This article highlights vital toxicities linked to anti-HER2 therapies, emphasizing their recognition across treatments as interstitial lung disease, diarrhea, or left ventricular dysfunction.

IMPLICATIONS FOR NURSING PRACTICES

Oncology nurses have a key role to play in detecting potential adverse effects of anti-HER2 therapies. The development of new drugs, as antibody-drug conjugates, with a distinct toxicity profile makes it necessary for us to be updated on the management of these new toxicities.

The inhibitory effect of trastuzumab on BT474 triple‑positive breast cancer cell viability is reversed by the combination of progesterone and estradiol

Breast cancer expressing the estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) is known as triple-positive (TPBC). TPBC represents 9-11% of breast cancer cases worldwide and is a heterogeneous subtype. Notably, TPBC presents a therapeutic challenge due to the crosstalk between the hormonal (ER and PR) and HER2 pathways. Patients with TPBC are treated with trastuzumab (TTZ); however, several patients treated with TTZ tend to relapse. The present study aimed to investigate the effect of the PR on inhibitory effect of TTZ on cell viability. BT474 cells (a model of TPBC) and BT474 PR-silenced cells were treated with either TTZ, progesterone (Pg), the PR antagonist mifepristone (RU486) or estradiol (E2) alone or in combination for 144 h (6 days). Cell viability assays and western blotting were subsequently performed. The results showed that Pg and E2 interfered with the inhibitory effect of TTZ on cell viability and this effect was potentiated when both hormones were combined. Pg was revealed to act through the PR, mainly activating the PR isoform B (PR-B) and inducing the protein expression levels of CDK4 and cyclin D1; however, it did not reactivate the HER2/Akt pathway. By contrast, E2 was able to increase PR isoform A (PR-A) expression, which was inhibited by Pg. Notably, in most of the experiments, RU486 did not antagonize the effects of Pg. In conclusion, Pg and E2 may interfere with the inhibitory effect of TTZ on cell viability through PR-B activation and PR-A inactivation.

Clinical characteristics and treatment outcomes of HER2 mutation and HER2 fusion in 22 patients with advanced breast cancer

BACKGROUND

The clinical characteristics and efficacy of human epidermal growth factor receptor-2 (HER-2)-directed agents against HER2 mutations and HER2 fusions in breast cancer are obscure due to their low frequency.

METHODS

We conducted a retrospective study in patients with advanced breast cancer harboring HER2 mutations and/or HER2 fusions between January 1, 2017 and January 1, 2021.

RESULTS

Among a total of 22 patients, 17 HER2 mutations were detected, including L755S, S310F, R100=, V777L, R897W, T862A, 440-17C > G, H878Y, V842I, 73 + 9G > C, T278fs, E1069K, L755P, 226-11C > T, 574 + 12C>T, L114V and P128L. The majority of patients had ductal carcinoma, which mostly coexisted with HER2 amplification/overexpression. The median progression-free survival (PFS) of the 22 patients was 6.9 months (95% CI: 4.7, 9.1) in the first-line setting. The median PFS of patients who received first-line trastuzumab-based regimens was significantly longer than that of patients who received a first-line tyrosine kinase inhibitor (TKI) (10.8 months [95% CI: 2.9, 18.7] vs. 1.9 months [95% CI: 0.8, 3.0], p < 0.005). A total of 14 patients were treated with anti-HER2 antibody-drug conjugate (ADC), among whom the median treatment line of first-time of administration of anti-HER2 ADC was 4.5 (range, 1-10). Anti-HER2 ADC reached an objective response rate (ORR) of 42.9%, a disease control rate (DCR) of 85.7% and a median PFS of 7.3 months (95% CI: 4.4-10.1) from the first-time of administration.

CONCLUSION

Our data demonstrated the clinical benefit of anti-HER2 treatment in Chinese breast cancer patients harboring HER2 mutation and/or HER2 fusion. The value of immunotherapy and treatment selection among individual HER2 variants needs further study.

Metastatic HER2-Positive Breast Cancer: Is There an Optimal Sequence of Therapy?

OPINION STATEMENT

Approximately 20% of breast cancers overexpress human epidermal growth factor receptor 2 (HER2+), conferring a particularly aggressive subtype of the disease with an increased risk for the development of systemic and brain metastases. However, the advent of trastuzumab and more recently several other HER2-targeting novel therapies has led to significant improvements in the prognosis, making the diagnosis a "double-edged sword." The current standard first-line therapy for patients with HER2+ metastatic breast cancer (MBC) is a taxane combined with trastuzumab and pertuzumab. Trastuzumab deruxtecan should be used preferentially in the second line, with the only caveat being patients with CNS involvement where the tucatinib, capecitabine, and trastuzumab regimen could be considered. In the third line setting, given the survival benefits demonstrated with the tucatinib regimen in patients with and without CNS metastases, this is the preferred strategy. In the fourth line and beyond, there is no clear standard. Options include margetuximab in combination with chemotherapy, neratinib + capecitabine, or trastuzumab + chemotherapy. There are several novel therapies under investigation reporting promising results in the late-line setting. The treatment landscape of HER2-positive advanced disease is evolving constantly, with several active therapies being moved to the early-stage setting. Accordingly, it will be critical to identify biomarkers and mechanisms of resistance to optimize therapy selection and maximize patient outcomes and quality of life. Here, we provide an overview of the current and future management of HER2-positive advanced breast cancer and address the specific scenarios which may impact treatment selection including triple-positive breast cancer and the presence of brain metastases. Finally, we highlight promising novel treatments and ongoing trials that may impact future treatment sequencing.

Predictive biological factors for late survival in patients with HER2-positive breast cancer

The human epidermal growth factor receptor-2 (HER2) enriched subtype of breast cancer is associated with early recurrence, mostly within 5 years. However, anti-HER2 therapies have improved outcomes and their benefits persist in the long term. This study aimed to determine predictive factors for late survival in patients with HER2-positive breast cancer. We analyzed 20,672 patients with HER2-positive stage I-III breast cancer. The patients were divided into two groups based on a follow-up period of 60 months. The multivariate analysis of factors associated with poor overall survival included old age, advanced pathologic tumor size stage (pT), advanced pathologic regional lymph node stage (pN), high histological grade, presence of lymphatic and vascular invasion, and HR-negative status within 60 months. In the breast cancer-specific survival (BCSS) of the > 60 months follow-up group, the hazard ratios (HRa) based on pN-negative were 3.038, 3.722, and 4.877 in pN1 (p = 0.001), pN2 (p < 0.001), and pN3 (p < 0.001), respectively. Only pT4 level was statistically significant in the pT group (HRa, 4.528; p = 0.007). Age (HRa, 1.045, p < 0.001) and hormone receptor-positive status (HRa, 1.705, p = 0.022) were also associated to worse BCSS. Although lymphatic invasion was not significantly associated with BCSS, there was a tendency toward a relationship (p = 0.079) with worse BCSS. In HER2-positive breast cancer patients, node status had a more significant relationship with long-term prognosis than T stage. Patients with HER2-positive breast cancer who have T4 or node-positive should be considered for clinical observation and education beyond 5 years.

Carbonic anhydrases reduce the acidity of the tumor microenvironment, promote immune infiltration, decelerate tumor growth, and improve survival in ErbB2/HER2-enriched breast cancer

BACKGROUND

Carbonic anhydrases catalyze CO₂/HCO₃^- buffer reactions with implications for effective H⁺ mobility, pH dynamics, and cellular acid-base sensing. Yet, the integrated consequences of carbonic anhydrases for cancer and stromal cell functions, their interactions, and patient prognosis are not yet clear.

METHODS

We combine (a) bioinformatic analyses of human proteomic data and bulk and single-cell transcriptomic data coupled to clinicopathologic and prognostic information; (b) ex vivo experimental studies of gene expression in breast tissue based on quantitative reverse transcription and polymerase chain reactions, intracellular and extracellular pH recordings based on fluorescence confocal microscopy, and immunohistochemical protein identification in human and murine breast cancer biopsies; and (c) in vivo tumor size measurements, pH-sensitive microelectrode recordings, and microdialysis-based metabolite analyses in mice with experimentally induced breast carcinomas.

RESULTS

Carbonic anhydrases-particularly the extracellular isoforms CA4, CA6, CA9, CA12, and CA14-undergo potent expression changes during human and murine breast carcinogenesis. In patients with basal-like/triple-negative breast cancer, elevated expression of the extracellular carbonic anhydrases negatively predicts survival, whereas, surprisingly, the extracellular carbonic anhydrases positively predict patient survival in HER2/ErbB2-enriched breast cancer. Carbonic anhydrase inhibition attenuates cellular net acid extrusion and extracellular H⁺ elimination from diffusion-restricted to peripheral and well-perfused regions of human and murine breast cancer tissue. Supplied in vivo, the carbonic anhydrase inhibitor acetazolamide acidifies the microenvironment of ErbB2-induced murine breast carcinomas, limits tumor immune infiltration (CD3⁺ T cells, CD19⁺ B cells, F4/80⁺ macrophages), lowers inflammatory cytokine (Il1a, Il1b, Il6) and transcription factor (Nfkb1) expression, and accelerates tumor growth. Supporting the immunomodulatory influences of carbonic anhydrases, patient survival benefits associated with high extracellular carbonic anhydrase expression in HER2-enriched breast carcinomas depend on the tumor inflammatory profile. Acetazolamide lowers lactate levels in breast tissue and blood without influencing breast tumor perfusion, suggesting that carbonic anhydrase inhibition lowers fermentative glycolysis.

CONCLUSIONS

We conclude that carbonic anhydrases (a) elevate pH in breast carcinomas by accelerating net H⁺ elimination from cancer cells and across the interstitial space and (b) raise immune infiltration and inflammation in ErbB2/HER2-driven breast carcinomas, restricting tumor growth and improving patient survival.

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.

Breast Cancer Subtypes in Northern Thailand and Barriers to satisfactory survival outcomes

Background:

The incidence of breast cancer (BC) in Thailand has been rising at an alarming rate. The annual incidence of BC in Thailand has doubled over a span of 15 years. A retrospective study was conducted with the primary objective of assessing and comparing survival rates of patients with BC, stratified by subtype of BC.

Methods:

A retrospective study was implemented for a cohort of women receiving a diagnosis of invasive BC with the objective of assessing and comparing their overall survival, stratified by BC subtype. Thai women receiving a diagnosis of their first primary invasive BC between January 2006 and December 2015 at Chiang Mai University Hospital were studied with 3,150 cases meeting the eligible criteria.

Results:

The median follow-up time was 4.9 years (Inter Quartile Range: 2.8–7.7). The most common diagnosed subtype was luminal B-like (n = 1,147, 36.4%). It was still the most prevalent subtype (35.8%) in women younger than 40 years and the 40–60 age-group, The proportion of patients with TNBC is the highest in women aged less than 40 years with 19.3% compared to the other age categories. Finally, among women older than 60 years, the proportion of each subtype was relatively uniform. Most women received a diagnosis of stage II disease. Triple negative subtype increased overall mortality in advanced staging (stages III and IV) (aHR:1.42, 95% CI: 0.96–2.11). The 5-year overall survival rate was found in luminal A-like at 82.8%, luminal B-like at 77.6%, HER-2 enriched at 66.4% and triple negative subtype at 64.2%.

Conclusion:

The histologic subtype, correlated with age and staging influenced the OS. Our results confirmed the association of triple negative BC with poor prognosis especially in advanced stage. The adjuvant medical treatment in our country could not be accessible in some group of patients, so the results of treatment and survival especially HER-2 enriched are lower than other countries without treatment barrier.

Prognostic nomogram for female patients suffering from non-metastatic Her2 positive breast cancer: A SEER-based study

This paper aimed at constructing and validating a novel prognostic nomogram, so that physicians forecast the overall survival (OS) rates of female patients suffering from non-metastatic human epidermal growth element receptor-2 (HER2) positive breast. Information of primary female her2 positive breast cancer patients without metastasis was obtained from the Surveillance, Epidemiology, and End Results (SEER) database with given inclusion and exclusion standards. Independent variables were obtained greatly by performing univariable and multivariate analyses. Based on those independent predictors, a novel prognostic nomogram was constructed for predicting the survival of those with 3- and 5-year OS. Then, concordance index (C-index), receiver operating characteristic curve (ROC), and calibration plot were adopted for the assessment of the predictive power of the nomogram. A total of 36,083 eligible patients were classified into a training cohort (n = 25,259) and a verification cohort (n = 10,824) randomly. According to the identification of multivariate analysis, survival was predicted by age at diagnosis, marital status, race, site, T stage, N stage, progesterone receptor (PR) status, estrogen receptor (ER) status, surgery, radiation, and chemotherapy independently. A nomogram was established by applying the training cohort. The nomogram displayed excellent discrimination and performance as indicated by the C-index (0.764, 95% confidence interval: 0.756-0.772), and the 3- and 5-year area under the curve of ROC (AUC) values (0.760 and 0.692 respectively). The calibration plots for forecasting the 3- and 5-year OS were in great agreement. The OS for female her2 positive breast cancer patients without metastasis was predicted by constructing a nomogram on basis of the SEER database. A precise survival prediction could be offered for each patient.

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.

Developments in the Management of Metastatic HER2-Positive Breast Cancer: A Review

Approximately 20% of breast cancers overexpress human epidermal growth factor receptor 2 (HER2), providing an actionable target for many different therapies. In the metastatic setting, prognosis has improved greatly with the use of anti-HER2 drugs such as trastuzumab, pertuzumab, and trastuzumab-emtansine. In the third line setting and beyond, several emerging treatments have shown benefits, including novel small molecule targeted agents and antibody-drug conjugates. Systemic treatment of brain metastases in HER2-positive patients and the role of endocrine-based treatment for patients with hormone receptor (HR) positive disease remain areas of research interest. This article will review the current approach to systemic management of metastatic HER2-positive breast cancer in Canada, and present novel treatments that may be available in the near future.

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.

The impact of hormone receptor on the clinical outcomes of HER2-positive breast cancer: a population-based study

BACKGROUND

To investigate the impact of hormone receptor (HR) on the clinicopathological characteristics and prognosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer.

METHODS

Using the Surveillance, Epidemiology, and End Results database, we enrolled patients diagnosed with HER2-positive breast cancer between 2010 and 2016, which were successively assessed for eligibility and categorized into HR + /HER2 + and HR-/HER2 + subgroups. Clinicopathological characteristics were undergone comparative analyses with the baseline distinctions calibrated by propensity score matching, while the survival outcomes were compared using Kaplan-Meier method with log-rank tests.

RESULTS

A total of 46,803 HER2-positive breast cancer patients were identified, of which 32,919 individuals were HR + /HER2 + subtype and 13,884 individuals were HR-/HER2 + subtype, respectively. Comparatively, HR + /HER2 + breast cancer presented a lower histological grade, a smaller tumor size, a lower nodal involvement, and a lower rate of de novo stage IV disease. Substantial heterogeneity was detected in the metastatic patterns of organ-specific involvement between the two subgroups with initial metastasis. Overall, patients with HR + /HER2 + tumors had increasingly favorable prognosis in terms of overall survival and breast cancer-specific survival than patients with the HR-/HER2 + subtype. However, this kind of tendency exhibited disparities associated with HR-specific subtypes based on estrogen receptor (ER) and progesterone receptor (PgR) status, in which ER-/PgR + tended to present the worst prognosis.

CONCLUSION

This study revealed profound heterogeneity associated with HR status in the clinical outcomes of HER2-positive breast cancer regarding clinicopathological features, metastatic patterns, and prognosis. Prospective studies to optimize therapeutic strategies for HER2-positive subgroups are warranted.

Clinical features of patients with HER2-positive breast cancer and development of a nomogram for predicting survival

Background

Different estrogen receptor (ER) and progesterone receptor (PR) expression patterns have important biological and therapeutic implications in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, little is known about hormone receptor (HR)-positive and triple-positive subtypes, making therapy selection and survival prognosis difficult. This study investigated the clinical characteristics and nomogram-predicted survival of patients with HER2-positive breast cancer.

Materials and methods

Data on patients with HER2-positive breast cancer were retrieved from the Surveillance, Epidemiology, and End Results database. Comparisons were carried out between single HR-positive and double HR-positive/double HR-negative subtypes. A nomogram-based model of predicted outcomes was developed.

Results

This cohort study included 34 819 patients with breast cancer (34 606 women and 213 men). Single HR-positive and double HR-positive/double HR-negative subtypes showed distinct clinicopathological characteristics. Multivariable Cox regression analysis showed that patients with ER-positive/PR-negative/HER2-positive [hazard ratio (HR) = 1.24; 95% confidence interval (CI): 1.14-1.39], ER-negative/PR-positive/HER2-positive (HR = 1.56; 95% CI: 1.23-1.97), and ER-negative/PR-negative/HER2-positive (HR = 1.56; 95% CI: 1.43-1.70) subtypes had worse breast cancer-specific survival than patients with the triple-positive subtype. Thirteen clinical parameters were included as prognostic factors in the nomogram: age, sex, race, grade, histology type, bone, brain, liver, and lung metastasis, TNM (tumor–node–metastasis) staging, and molecular subtype. The C-index was 0.853 (95% CI: 0.845-0.861). Calibration plots indicated that the nomogram-predicted survival was consistent with the recorded 3-year and 5-year prognoses.

Conclusions

Significant differences in survival rates were observed between single HR-positive and double HR-positive/double HR-negative subtypes. A nomogram accurately predicted survival. Different treatment strategies may be required for HER2-positive patients with single HR-positive and double HR-positive tumors to ensure optimal treatment and benefits.

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Significant differences in survival were observed in single HR-positive and double HR-positive/double HR-negative subtypes.

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A nomogram based on molecular subtypes of HER2-positive breast cancer accurately predicted breast cancer-specific survival.

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Different treatment strategies may be required for HER2-positive breast cancer to ensure optimal treatment and benefits.

Dissecting the biological heterogeneity of HER2-positive breast cancer

HER2-positive (HER2+) breast cancer (BC) is a heterogenous and multifaceted disease, with interesting therapeutic implications. First, all intrinsic molecular subtypes can be identified in HER2+ tumors, with the HER2-enriched being the most frequent. Such subtypes do not differ much from their counterparts in HER2-negative disease, apart for the high expression of genes in/near the HER2 amplicon on chromosome 17. Intrinsic subtyping, along with the quantification of ERBB2 mRNA levels, is associated with higher rates of pathologic complete response across neoadjuvant trials of dual HER2 blockade and might help select patients for de-escalation and escalation treatment strategies. Secondly, HER2+ tumors have a broad range of DNA alterations. ERBB2 mutations and alterations in the PI3K/Akt/mTOR pathway are among the most frequent and might predict benefit from potent pan-HER, PI3K and mTOR inhibitors. Moreover, HER2+ tumors are usually infiltrated by lymphocytes. These tumor infiltrating-lymphocytes (TILs) predict response to neoadjuvant anti-HER2-based treatment and exert a prognostic role. PD-L1, detected in ∼42 % of HER2+ BC, might also be useful to define patients responding to novel anti-PD1/PD-L1 immunotherapies. New multiparametric clinicopathologic and genomic tools accounting for this complexity, such as HER2DX, are under development to define more tailored treatment approaches. Finally, HER2-targeted antibody-drug conjugates (ADC) such as trastuzumab deruxtecan might be active in tumors with low expression of HER2. Overall, there is a need to molecularly characterize and develop novel targeted therapies for HER2+ disease.

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Almost 50 % of HER2+ breast cancer (BC) are molecularly HER2-Enriched (HER2-E).

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Most relevant mutations are found in ERBB2 (∼4 %) and PI3K/AKT/mTOR pathway (>30 %).

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Tumor infiltrating lymphocytes are frequent, predictive and prognostic in HER2+ BC.

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HER2 heterogeneity and HER2 low status are gaining therapeutic relevance.

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New treatments need to consider HER2+ molecular and microenvironmental complexity.

Current and Future Management of HER2-Positive Metastatic Breast Cancer

Human epidermal growth factor receptor 2 (HER2) is overexpressed and/or amplified in approximately 20% of breast cancers, conferring an aggressive tumor behavior but also an opportunity for targeted therapies. In the advanced setting, the prognosis of patients suffering from this disease has greatly improved after the introduction of new anti-HER2 drugs beyond trastuzumab. For most patients, a taxane combined with trastuzumab and pertuzumab in the first-line setting, followed by trastuzumab-emtansine in second line, should be considered the standard of care today. However, chemo-free anti-HER2 strategies in hormone receptor-positive, HER2-positive breast cancer could also be considered in selected patients. In the third-line setting and beyond, several emerging anti-HER2 therapies are becoming available, including tucatinib, fam-trastuzumab deruxtecan-nxki (DS-8201a), neratinib, and margetuximab-cmkb. In addition, new compounds and combinations are showing promising results in the late-line setting. The treatment landscape of HER2-positive advanced disease is evolving constantly, active drugs such as pertuzumab and trastuzumab-emtansine are moving to early-stage, many biomarkers, including quantification of HER2 itself, are being explored to improve patient selection, and patient populations with specific needs are emerging, such as those with brain metastasis. Here, we provide an overview of the current and future management of HER2-positive advanced breast cancer.

Adjuvant endocrine therapy in HER2-positive breast cancer patients: systematic review and meta-analysis

Background

Approximately 50% of human epidermal growth factor receptor 2 (HER2)-positive breast cancer lesions express hormone receptors. These tumors present a unique therapeutic challenge, and the optimal endocrine therapeutic approach remains controversial. We aimed to study the optimal adjuvant endocrine therapy in this setting, to better establish the basis for clinical recommendations in HER2-positive disease.

Methods

We conducted a literature search up to May 2020, in which we identified randomized controlled trials (RCTs) that investigated the efficacy of various adjuvant hormonal therapies among premenopausal and postmenopausal patients with hormone receptor (HR)-positive, HER2-positive early breast cancer. Disease-free survival (DFS) was calculated with the random effect model and hazard ratios (HRs) with 95% confidence intervals (CI).

Results

Six RCTs (N = 5390 patients) were included in the final analysis. There was no significant difference in DFS between adjuvant treatment with aromatase inhibitors and tamoxifen (HR 0.99, 95% CI 0.68-1.44, P = 0.96). Furthermore, after omitting the ALTTO trial, as it did not randomize patients to hormonal therapy, no significant difference was observed between the two protocols (HR 1.06, 95% CI 0.65-1.73, P = 0.81).

Conclusion

Our study demonstrates similar DFS with tamoxifen and aromatase inhibitors as adjuvant endocrine treatment in HER2-positive HR-positive early-stage breast cancer patients. Future larger prospective studies focusing on the various contemporary endocrine regimens are warranted to validate our findings.

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Optimal adjuvant endocrine therapy for early-stage breast cancer with co-expression of HER2 and hr is unclear.

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Our analysis demonstrated no difference in disease-free survival between selected endocrine regimens among these patients.

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Study strength includes longer follow-up, premenopausal patients and current HER2 regimens and combinations.

Clinical significance of HER2 status in T1bN0 breast cancer: a nationwide study from the Korean Breast Cancer Society

PURPOSE

The prognosis of patients with node-negative T1b tumors according to human epidermal growth factor receptor 2 (HER2) status is not known. This group of patients has not been studied in the available randomized trials. The objective of this study was to evaluate the survival of patients in a monoethnic group diagnosed with T1b lymph node-negative breast cancer depending on HER2 status.

METHODS

We analyzed 3110 patients with T1bN0M0 breast cancer whose data were deposited into the Korean Breast Cancer Society Registry database between 2000 and 2009. Overall survival (OS) and breast cancer-specific survival (BCSS) were compared according to HER2 status.

RESULTS

Among all patients, 494 (15.9%) had HER2-positive breast cancer. At a mean follow-up of 93 months, 108 deaths and 86 breast cancer-specific deaths were noted among all patients. There was no significant difference in OS between the HER2-negative and HER2-positive groups (p = 0.103). The same result was observed for BCSS. However, in the subgroup of estrogen receptor (ER)-positive women, HER2-negative patients had a better BCSS prognosis than HER2-positive patients (p = 0.025). Multivariate analysis also indicated a significant difference in BCSS in the ER-positive subgroup (HR 2.60; 95% CI 1.15-5.87; p = 0.021).

CONCLUSION

This study analyzed a large nationwide and monoethnic cohort and found a significant difference only in BCSS in the ER-positive subgroup according to HER2 status. Anti-HER2 therapy may be considered in HER2-positive and ER-positive patients with small, node-negative breast cancer.

Validation of the Prognostic Stage of American Joint Committee on Cancer Eighth Edition Staging Manual in Invasive Lobular Carcinoma Compared to Invasive Ductal Carcinoma and Proposal of a Novel Score System

Purpose: The objective of this study was to evaluate the American Joint Committee on Cancer (AJCC) pathological prognostic stage among patients with invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) and to propose a modified score system if necessary.

Methods: Women diagnosed with IDC and ILC during 2010–2015 in the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively identified. Disease-specific survival (DSS) and overall survival (OS) were estimated by Kaplan–Meier method. Predictive performances of different staging systems were evaluated based on Harrell concordance index (C-index) and Akaike Information Criterion (AIC). Multivariate Cox models were conducted to build preferable score systems.

Results: A total of 184,541 female patients were included in the final analyses, with a median follow-up of 30.0 months. In IDC cohort, the pathological prognostic stage (C-index, 0.8281; AIC, 110274.5) was superior to the anatomic stage (C-index, 0.8125; AIC, 112537.0; P < 0.001 for C-index) in risk stratification with respect to DSS. In ILC cohort, the prognostic stage (C-index, 0.8281; AIC, 7124.423) didn't outperform the anatomic stage (C-index, 0.8324; AIC, 7144.818; P = 0.748 for C-index) with respect to DSS. Similar results were observed with respect to OS. The score system defined by anatomic stage plus grade plus estrogen receptor and progesterone receptor (AS+GEP) allows for better staging (C-index, 0.8085; AIC, 7178.448) for ILC patients.

Conclusion: Compared with anatomic stage, the pathological prognostic stage provided more accurate stratification for patients with IDC, but not for patients with ILC. The AS+GEP score system may fit ILC tumors better.

Towards personalized treatment for early stage HER2-positive breast cancer

Advances in HER2-targeted therapies have improved the survival of patients with HER2-positive breast cancer. The standard-of-care treatment for localized disease has been chemotherapy and 1 year of adjuvant HER2-targeted therapy, typically with the anti-HER2 antibody trastuzumab. Despite the effectiveness of this treatment, disease relapse occurs in a subset of patients; thus, focus has been placed on escalating treatment by either combining different HER2-targeted agents or extending the duration of HER2-targeted therapy. Indeed, dual HER2-targeted therapies and extended-duration anti-HER2 therapy, as well as adjuvant therapy with the anti-HER2 antibody-drug conjugate T-DM1, have all been approved for clinical use. Emerging evidence suggests, however, that some patients do not derive sufficient benefit from these additional therapies to offset the associated toxicities and/or costs. Similarly, the universal use of chemotherapy might not benefit all patients, and treatment de-escalation through omission of chemotherapy has shown promise in clinical trials and is currently being explored further. The future of precision medicine should therefore involve tailoring of therapy based on the genetics and biology of each tumour and the clinical characteristics of each patient. Predictive biomarkers that enable the identification of patients who will benefit from either escalated or de-escalated treatment will be crucial to this approach. In this Review, we summarize the available HER2-targeted agents and associated mechanisms of resistance, and describe the current therapeutic landscape of early stage HER2-positive breast cancer, focusing on strategies for treatment escalation or de-escalation.

Benefits of adjuvant treatment including trastuzumab in HER2-positive pT1a-bN0M0 breast cancer: a systematic review and meta-analysis

BACKGROUND

Although trastuzumab has been shown to be beneficial for treating patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer, information regarding its benefits is limited to very low-risk cases with tumours ≤1 cm and without lymphatic metastases (pT1abN0). The present meta-analysis integrates information from literature and determines the benefit of trastuzumab in pT1abN0, HER2-positive breast cancer patients.

METHODS

PubMed, MEDLINE, and EMBASE databases were searched for studies published before Sep 30, 2019. Our primary endpoint was tumor recurrence, whether provided as overall or distant recurrences.

RESULTS

Seven studies involving 1,181 patients with pT1abN0, HER2-positive breast cancer were included in the systemic review. The median follow-up periods ranged from 37 to 78 months. The patients in the trastuzumab arm had generally inferior profiles such as higher rate of T1b, grade 3, and hormone negative cases, among available studies. Concomitant chemotherapy was more commonly applied in the trastuzumab arm (75-100% vs. 0-42%), and the hormone therapy application was similar in both arms (20-66%). In a pooled analysis of seven available studies, patients treated with trastuzumab had less overall recurrence relative to controls, with an odds ratio of 0.201 [95% confidence interval (CI): 0.100-0.404, P<0.001]. Five studies were available for a pooled analysis of distant recurrence. Although the results were not significant (P=0.115), distant recurrence did not occur in 237 patients treated with trastuzumab, but did occur in 16 out of 436 control patients. The odds ratio for distant recurrence was 0.328 (95% CI: 0.082-1.311).

CONCLUSIONS

The adjuvant treatment including trastuzumab was shown to reduce overall recurrence. Distant recurrence may also be reduced, as it did not occur among the 237 patients who underwent trastuzumab treatment.

Trastuzumab plus adjuvant chemotherapy for human epidermal growth factor receptor 2 (HER2)-positive early-stage breast cancer: A real-world retrospective study in Chinese patients

Objective

To assess the long-term effectiveness and safety of trastuzumab in adjuvant therapy for Chinese patients with early-stage human epidermal growth factor 2 (HER2)-positive breast cancer in a real-world setting.

Methods

This retrospective observational study analyzed the medical records of HER2-positive breast cancer patients between 2000 and 2012 at the Chinese Academy of Medical Sciences. Patients who received adjuvant chemotherapy alone or adjuvant chemotherapy followed by/combined with trastuzumab were included. The Kaplan-Meier method was used to estimate disease-free survival (DFS) and overall survival (OS). Hazard ratios (HR) and 95% confidence intervals (95% CI) were calculated using the Cox regression model.

Results

Of the 1,348 patients analyzed, 909 received chemotherapy alone and 439 received chemotherapy plus trastuzumab. The 3-year, 5-year and 10-year DFS rates were 83.70%, 76.38% and 68.94%, respectively, in the chemotherapy-alone cohort, and 90.21%, 86.19% and 83.45% in the chemotherapy plus trastuzumab cohort. The 3-year, 5-year and 10-year OS rates were 96.10%, 91.40% and 81.88% in the chemotherapy-alone cohort, and 98.17%, 94.91% and 90.01% in the chemotherapy plus trastuzumab cohort. The chemotherapy plus trastuzumab group had a significantly lower risk of disease recurrence and death than the chemotherapy-alone group (DFS: HR=0.50, 95% CI, 0.37-0.68; P<0.001; OS: HR=0.53, 95% CI, 0.34-0.81; P=0.004) after adjusting for covariates. In the 439 patients treated with trastuzumab, multivariate analysis suggested that lymph node positivity, higher T stages, and hormone receptor-negative status were significantly associated with higher risks of disease recurrence, and lymph node positivity and hormone receptor-negative status were significantly associated with higher risks of death. Grade 3/4 adverse events (incidence ≥1%) were more common in patients receiving trastuzumab (54.44%vs. 15.73%).

Conclusions

Early-stage HER2-positive breast cancer patients treated with trastuzumab plus adjuvant chemotherapy have a significant survival benefit compared with chemotherapy-alone in real-world settings. Lymph node positivity, hormone receptor-negative status, and higher T stages may be associated with higher risks of recurrence, and effective therapy for patients with these factors is required.

Imaging and Clinicopathologic Features Associated With Pathologic Complete Response in HER2-positive Breast Cancer Receiving Neoadjuvant Chemotherapy With Dual HER2 Blockade

BACKGROUND

In human epidermal growth factor receptor 2-positive (HER2⁺) breast cancer, the incorporation of a dual HER2 blockade into neoadjuvant chemotherapy (NAC) has been shown to induce a higher rate of pathologic complete response (pCR). The purpose of this study was to investigate whether pretreatment imaging and clinicopathologic features show any association with pCR in HER2⁺ breast cancer receiving NAC plus dual blockade.

MATERIALS AND METHODS

This retrospective study evaluated 94 consecutive patients (mean age, 49.8 ± 9.9 years) with HER2⁺ breast cancer who underwent NAC plus dual blockade with trastuzumab and pertuzumab between April 2016 and June 2018. All patients underwent mammography, ultrasound, and magnetic resonance imaging prior to NAC. Clinicopathologic and imaging features acquired before NAC were evaluated for their ability to predict the pathologic response after surgery. Multivariate analysis was used to identify independent predictors of pCR.

RESULTS

Fifty patients (53.2%) showed pCR and 44 (46.8%) did not. According to a univariate analysis, fine pleomorphic/fine linear or linear-branching calcification morphology on mammography, parallel orientation on ultrasound, intratumoral high signal intensity on T2-weighted magnetic resonance imaging, progesterone receptor negativity, and high levels of tumor-infiltrating lymphocytes were associated with pCR. On multivariate analysis, fine pleomorphic/fine linear or linear-branching calcification morphology on mammography (odds ratio [OR], 7.23), progesterone receptor negativity (OR, 6.76), and a high tumor-infiltrating lymphocyte level (OR, 5.92) remained significant independent factors associated with pCR.

CONCLUSION

Several pretreatment imaging and clinicopathologic features were shown to be independent variables predicting pCR in patients with HER2⁺ breast cancer receiving NAC with dual blockade.

Molecular portraits and trastuzumab responsiveness of estrogen receptor-positive, progesterone receptor-positive, and HER2-positive breast cancer

Background: Estrogen receptor-positive, progesterone receptor-positive, and HER2-positive breast cancers (triple-positive breast cancers, TPBCs) account for 5% to 10% of all breast cancers. The clinical and molecular features of TPBCs remain elusive. In this study, we aim to analyze the multiomics landscape and responsiveness of TPBCs to trastuzumab. Methods: We employed five cohorts. The first cohort was from the Surveillance, Epidemiology, and End Results database (n=32,056) and was used to determine the clinical characteristics of TPBC. The second, third and fourth cohorts were from The Cancer Genome Atlas (n=162), GSE2603 (n=37) and GSE2109 (n=30) datasets, respectively, and were used to examine the genomic features and molecular classification of TPBC. The fifth cohort comprised TPBC patients treated at Fudan University Shanghai Cancer Center (FUSCC, n=171) and was used to investigate an immunohistochemistry-defined luminal A-like subgroup of TPBC. Results: Patients with TPBC had a significantly better prognosis than those with ER-PR-HER2+ breast cancer. Genomic analysis revealed that TPBCs showed a lower TP53 mutation rate (30% vs. 69%, P < 0.001) and lower levels of HER2 mRNA and protein expression than ER-PR-HER2+ breast cancers. More than 40% of TPBCs were classified as the luminal A intrinsic subtype, with an even lower HER2 expression level. Based on the immunohistochemical detection of CDCA8, BCL2 and STC2, we identified a luminal A-like subgroup of TPBCs in the FUSCC cohort (CDCA8-negative, BCL2- and/or STC2-positive). Patients with luminal A-like TPBC had a better prognosis and benefited less from trastuzumab than those with TPBC of other subtypes. Conclusions: TPBCs consist of clinically and genomically heterogeneous subgroups that may require different therapeutic strategies. The luminal A-like subgroup of TPBCs is associated with a better prognosis and reduced benefit from trastuzumab.

The Use of Immunotherapy to Treat Metastatic Breast Cancer

This article reviews the principal attempts of immune-modulation or immune therapy in metastatic breast cancer. It considers their rationale and reports on results from the relevant key clinical trials. Immune-modulatory or immune-stimulating cytokines used alone or combined with conventional therapies is among the principal approaches of immune manipulation in breast cancer. As this issue has recently been reviewed by us, the aim of the current article is to discuss our updated and unpublished data on this topic. Overall survival in luminal (28 patients) and non-luminal (9 patients) molecular subtypes is 91 and 59 months respectively that is about two and half or three times longer than expected. Thereafter, we focus on monoclonal antibodies (mAb) based-therapies including novel strategies to overcome resistance to anti-HER2 mAb. The main vaccine platforms in different molecular subtypes and immune therapies in triple negative metastatic breast cancer (m-TNBC) are discussed in the last sections. Some phase III investigations have already changed the current clinical practice. In fact, pertuzumab plus trastuzumab and docetaxel is the recommended first line regimen in HER2 positive locally recurrent or metastatic breast cancer and bevacizumab plus paclitaxel or docetaxel is a reasonable option for m-TNBC. In some other observational or phase I/II studies on first-line trastuzumab plus chemotherapy and hormonal therapy and in that on HER2 peptide/protein vaccines promising although preliminary findings have been reported to be further validated. In the remaining studies, results were disappointing. In the future, finding new predictive biomarkers and exploring more suitable synergizing combinations, time and dose-dependent-scheduled sequences of currently and further investigated immunological approaches are main challenges.

Neratinib in Early-Stage Breast Cancer: A Profile of Its Use in the EU

Neratinib (Nerlynx^®) is an oral, irreversible pan-human epidermal growth factor receptor (HER) tyrosine kinase inhibitor of HER1, HER2 and HER4. Neratinib therapy for 12 months significantly reduced the risk of invasive disease recurrence or death relative to placebo at both 2 and 5 years post-randomization in the pivotal ExteNET trial in women with early-stage HER2-positive breast cancer who had completed adjuvant trastuzumab. Subgroup analyses showed that patients with hormone receptor (HRc)-positive disease derived greater benefit with neratinib than patients with HRc-negative disease, and patients who initiated neratinib within 1 year of completing trastuzumab had better outcomes than those who started treatment 1–2 years after trastuzumab. This led to the approval of neratinib in the EU as extended adjuvant therapy for patients with early-stage HRc-positive, HER2-positive breast cancer and who are less than 1 year from completion of prior adjuvant trastuzumab-based therapy. It is the first agent of its class to be approved in the EU in this setting. As with other tyrosine kinase inhibitors, diarrhoea, which was manageable with antidiarrhoeal prophylaxis and/or dose modifications, was the most common any-grade or grade ≥ 3 treatment-emergent adverse event with neratinib. Thus, current evidence indicates that neratinib provides a valuable option to reduce the risk of recurrence in this setting and has been included in the updated ESMO patient guide as an extended adjuvant therapy for some patients.

Clinical Differences in Triple-Positive Operable Breast Cancer Subtypes in Korean Patients: An Analysis of Korean Breast Cancer Registry Data

Purpose

Triple-positive breast cancer is defined by estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) positivity. Several systemic breast cancer therapies target hormonal and HER2 responsiveness. We compared clinical outcomes of triple-positive disease with those of HER2-enriched and luminal HER2-negative disease and investigated the clinical efficacy of anti-HER2 therapy for triple-positive disease.

Methods

We retrospectively compared overall and recurrence-free survival among cases included in the Korean Breast Cancer Society (KBCS) and Seoul St. Mary's Hospital breast cancer registries and the therapeutic efficacy of trastuzumab for triple-positive and HER2-enriched cases.

Results

KBCS registry data (2006–2010; median follow-up, 76 months) indicated that patients with triple-positive breast cancer had intermediate survival between those with luminal A and HER2-enriched subtypes (p<0.001). Trastuzumab did not improve overall survival among patients with triple-positive breast cancer (p=0.899) in contrast to the HER2-enriched subtype (p=0.018). Seoul St. Mary's Hospital registry data indicated similar recurrence-free survival outcomes (p<0.001) and a lack of improvement with trastuzumab among patients with triple-positive breast cancer (median follow-up, 33 months; p=0.800). Multivariate analysis revealed that patients with triple-positive breast cancer had better overall survival than those with HER2-enriched disease and similar survival as those with the luminal A subtype (triple-positive: hazard ratio, 1.258, p=0.118; HER2-enriched: hazard ratio, 2.377, p<0.001).

Conclusion

Our findings showed that anti-HER2 therapy was less beneficial for treatment of triple-positive breast cancer than for HER2-enriched subtypes of breast cancer, and the triple-positive subtype had a distinct prognosis.

Category "viewpoints and debates" Is trastuzumab as a single agent obsolete in early breast cancer? Yes

In 2005, two adjuvant trials revolutionised breast cancer treatment demonstrating a 50% reduction in relapses when trastuzumab was added to adjuvant chemotherapy. In order to improve further on these results three large phase III trials were conducted. ALTTO trial evaluated lapatinib. This trial was negative and lapatinib was quite toxic. ExteNET trial evaluated neratinib in patients who already had completed adjuvant treatment with trastuzumab. Neratinib reduced the risk of relapse by 27% and the drug is FDA approved. However 40% of patients experienced grade 3 diarrhoea and this toxicity profile will be an issue in daily practice. APHINITY trial evaluated a combination of pertuzumab and trastuzumab. Pertuzumab reduced the risk of relapse by 19% with a good toxicity profile. However the absolute invasive disease-free survival (IDFS) benefit at 4 years was only 1.7%. Despite this modest absolute benefit we believe that pertuzumab should be added to trastuzumab at least in two indications: first, in patients with node positive breast cancer, in whom the absolute IDFS benefit is 3.2% and qualify for a high clinical benefit based on ESMO magnitude of clinical benefit scale; second, in patients suitable for neoadjuvant chemotherapy. In this group, the absolute IDFS benefit could be estimated as high as 7% (starting pertuzumab in the neoadjuvant setting and following it in the adjuvant setting up to a total of 18 injections). Our arguments are developed in this viewpoint. Pertuzumab is approved in these two indications by FDA and EMA.

Extended Adjuvant Therapy with Neratinib Plus Fulvestrant Blocks ER/HER2 Crosstalk and Maintains Complete Responses of ER+/HER2+ Breast Cancers: Implications to the ExteNET Trial

PURPOSE

The phase III ExteNET trial showed improved invasive disease-free survival in patients with HER2⁺ breast cancer treated with neratinib versus placebo after trastuzumab-based adjuvant therapy. The benefit from neratinib appeared to be greater in patients with ER⁺/HER2⁺ tumors. We thus sought to discover mechanisms that may explain the benefit from extended adjuvant therapy with neratinib.Experimental Design: Mice with established ER⁺/HER2⁺ MDA-MB-361 tumors were treated with paclitaxel plus trastuzumab ± pertuzumab for 4 weeks, and then randomized to fulvestrant ± neratinib treatment. The benefit from neratinib was evaluated by performing gene expression analysis for 196 ER targets, ER transcriptional reporter assays, and cell-cycle analyses.

RESULTS

Mice receiving "extended adjuvant" therapy with fulvestrant/neratinib maintained a complete response, whereas those treated with fulvestrant relapsed rapidly. In three ER⁺/HER2⁺ cell lines (MDA-MB-361, BT-474, UACC-893) but not in ER⁺/HER2^- MCF7 cells, treatment with neratinib induced ER reporter transcriptional activity, whereas treatment with fulvestrant resulted in increased HER2 and EGFR phosphorylation, suggesting compensatory reciprocal crosstalk between the ER and ERBB RTK pathways. ER transcriptional reporter assays, gene expression, and immunoblot analyses showed that treatment with neratinib/fulvestrant, but not fulvestrant, potently inhibited growth and downregulated ER reporter activity, P-AKT, P-ERK, and cyclin D1 levels. Finally, similar to neratinib, genetic and pharmacologic inactivation of cyclin D1 enhanced fulvestrant action against ER⁺/HER2⁺ breast cancer cells.

CONCLUSIONS

These data suggest that ER blockade leads to reactivation of ERBB RTKs and thus extended ERBB blockade is necessary to achieve durable clinical outcomes in patients with ER⁺/HER2⁺ breast cancer.

Stromal PTEN determines mammary epithelial response to radiotherapy

The importance of the tumor-associated stroma in cancer progression is clear. However, it remains uncertain whether early events in the stroma are capable of initiating breast tumorigenesis. Here, we show that in the mammary glands of non-tumor bearing mice, stromal-specific phosphatase and tensin homolog (Pten) deletion invokes radiation-induced genomic instability in neighboring epithelium. In these animals, a single dose of whole-body radiation causes focal mammary lobuloalveolar hyperplasia through paracrine epidermal growth factor receptor (EGFR) activation, and EGFR inhibition abrogates these cellular changes. By analyzing human tissue, we discover that stromal PTEN is lost in a subset of normal breast samples obtained from reduction mammoplasty, and is predictive of recurrence in breast cancer patients. Combined, these data indicate that diagnostic or therapeutic chest radiation may predispose patients with decreased stromal PTEN expression to secondary breast cancer, and that prophylactic EGFR inhibition may reduce this risk.

Association of p27 and Cyclin D1 Expression and Benefit from Adjuvant Trastuzumab Treatment in HER2-Positive Early Breast Cancer: A TransHERA Study

Purpose: To assess the prognostic and predictive value of selected biomarkers involved in cell-cycle regulation or proliferation in patients with HER2-positive early breast cancer.Experimental Design: Protein expression of TOP2A, Ki67, cyclin D1, and p27 was immunohistochemically determined in tissue microarrays of surgical specimens from 862 patients randomized to trastuzumab (1 or 2 years; N = 561) and observation (N = 301) arms of the HERA trial. The primary analysis endpoint was disease-free survival (DFS). Biomarkers were examined as continuous or categorical variables (predefined cutoffs). Interaction terms between biomarkers and treatment were assessed in multivariate Cox models adjusted for variables of clinical interest.Results: A significant interaction was detected between p27 and treatment (adjusted P = 0.0049). Trastuzumab effect was significant in the p27-low subgroup (≤70% p27-positive tumor cells; N = 318). HR _{Comb Trast vs. Obs} 0.44, 95% CI, 0.29-0.65 (P < 0.001). No trastuzumab effect was observed in the p27-high subgroup N = 435; HR _{Comb Trast vs. Obs} 0.97, 95% CI, 0.66-1.44, P = 0.89), indicating that these patients derived little or no benefit from trastuzumab treatment. A prognostic effect of p27 on DFS was observed, with p27-high patients experiencing half the hazard of a DFS event compared with low ones (HR _{p27 High vs. Low} 0.49, 95% CI, 0.32-0.75). TOP2A, Ki67, and cyclin D1, as categorical variables were not predictive, whereas cyclin D1 as continuous variable was predictive of trastuzumab benefit.Conclusions: In TransHERA, patients with HER2-positive early breast cancer with low p27 expression in their tumors benefited from trastuzumab treatment, whereas patients with high p27 expression did not. Clin Cancer Res; 24(13); 3079-86. ©2018 AACR.

Adjuvant Trastuzumab Therapy for Early HER2-Positive Breast Cancer in Iran: A Cost-Effectiveness and Scenario Analysis for an Optimal Treatment Strategy

INTRODUCTION

Clinical guidelines have recommended a 1-year trastuzumab regimen as standard care for early human epidermal growth factor receptor 2 (HER2)-positive breast cancer; however, this recommendation can have a dramatic impact on total drug expenditures in middle-income countries (MICs). We performed a cost-effectiveness analysis from the Iranian healthcare perspective to find an optimum duration of trastuzumab use in Iran.

METHOD

We compared four treatment strategies comprising chemotherapy and varying durations of trastuzumab use (no trastuzumab, 6, 9 months, and 1 year), and a Markov model and probabilistic sensitivity analysis were used to estimate the costs and effects of the strategies. We then examined the cost effectiveness of the strategies at different willingness-to-pay (WTP) thresholds and ages at onset of treatment.

RESULTS

Incremental costs (versus no trastuzumab) were €8826 (6 months), €13,808 (9 months) and €18,588 (12 months), while incremental quality-adjusted life-years (QALYs) were 0.65 (6 months), 0.87 (9 months) and 1.14 (12 months). At a threshold of 3 × gross domestic product (GDP)/capita (€21,000/QALY) and for patients younger than 59 years, the 6-month protocol was most likely to be cost effective (probability of 42%). At a threshold of 4 × GDP/capita (€28,000/QALY), the 6-month and 1-year regimens were essentially equal in cost effectiveness (37 and 35%, respectively). At this WTP threshold, the 6-month and 1-year regimens were optimal strategies only for patients up to 66 and 44 years of age, respectively.

CONCLUSION

In contrast to clinical guidelines, 6 months of trastuzumab may be the most cost-effective option for Iran. The lower absolute WTP threshold and lower life expectancy compared with high-income countries are two crucial parameters in the cost effectiveness of interventions in MICs. It is therefore necessary to strike a balance between maximum population health and maintaining affordability in these countries.

Superimposable outcomes for sequential and concomitant administration of adjuvant trastuzumab in HER2-positive breast cancer: Results from the SIGNAL/PHARE prospective cohort

AIM

Adjuvant clinical trials in early human epidermal growth factor receptor 2 (HER2)-positive breast cancer have assessed either sequential or concomitant incorporation of trastuzumab with chemotherapy; only the North Central Cancer Treatment Group (NCCTG)-N9831 trial prospectively compared both modalities. In routine trastuzumab has been incorporated into a concurrent regimen with taxane chemotherapy instead of sequential modality on the basis of a positive risk-benefit ratio. This present study assessed sequential versus concomitant administration of adjuvant trastuzumab.

METHODS

A population combining patients from Protocol for Herceptin^® as Adjuvant therapy with Reduced Exposure (PHARE) a randomised phase III clinical trial (NCT00381901) and SIGNAL (RECF1098) a prospective study specifically designed for Genome-wide Association Studies (GWAS) analyses was studied. In this cohort with 58 months of median follow-up, the comparison in the HER2-positive group of adjuvant trastuzumab and chemotherapy modalities was based on a propensity score methodology. Treatment modalities were based on physician's choice and comparisons adjustment were made by a propensity score methodology. Overall Survival (OS) and Disease-Free Survival (DFS) were estimated using the Kaplan-Meier method, and comparisons between groups were based on the log rank test.

RESULTS

The SIGNAL/PHARE cohort included 11,728 breast cancer cases treated in adjuvant setting; some 5502 of them with HER2-positive tumour: 34.5% (1897/5502) were treated by sequential and 65.5% (3605/5502) by concomitant modality of administration for taxane-chemotherapy and trastuzumab. The adjusted comparison found similar OS (HR = 1.01; 95% CI: 0.86-1.19) and similar DFS (HR = 1.08; 95% CI: 0.96-1.21).

CONCLUSION

These results suggest that the sequential administration of trastuzumab given after the completion of adjuvant chemotherapy might be as valid as the concomitant administration of trastuzumab and taxane chemotherapy in the adjuvant setting.

PTEN expression as a predictor for the response to trastuzumab-based therapy in Her-2 overexpressing metastatic breast cancer

Background

Even though trastuzumab is an effective therapy in early stage Her-2+ breast cancer, 40–50% of advanced Her-2+ breast cancer patients develop trastuzumab resistance. A potential resistance mechanism is aberrant downstream signal transmission due to loss of phosphatase and tensin homologue (PTEN). This study investigated the relationship between the expression of PTEN and trastuzumab response in Her-2 overexpressing metastatic breast cancer patients.

Methods

Between 2000 and 2007, 164 patients with Her-2+ metastatic breast cancer received trastuzumab-based therapy in our institution. We analyzed PTEN status by immunohistochemistry of 115 available tumor tissues and analyzed associations with other histopathological parameters, response rate, progression free survival (PFS) and overall survival (OS) with a median follow-up of 60 months.

Results

Eighty patients were PTEN positive (69.6%) and 35 patients PTEN negative (30.4%). We found a significant association of the expression of PTEN and p53 (p = 0.041), while there was no association with grading, hormone receptor status, IGFR or MIB. We found significantly more cases with progressive disease under trastuzumab-based therapy in patients with PTEN positive breast cancers (p = 0.018), while there was no significant correlation with PFS or OS.

Conclusion

In Her-2-positive metastatic breast cancers, PTEN positivity was significantly associated with progressive disease, but not with PFS or OS.

Screening-relevant age threshold of 70 years and older is a stronger determinant for the choice of adjuvant treatment in breast cancer patients than tumor biology

Purpose

The 70-year threshold determines whether patients are eligible or not for the breast cancer screening program in Germany. It is not known whether this age threshold also influences the choice of adjuvant treatment and ultimate outcome.

Methods

3463 patients were analyzed from the clinical cancer registry Regensburg (Germany) with primary, non-metastatic invasive breast cancer diagnosed between 2000 and 2012. The distribution of tumor biological subtypes was evaluated in breast cancer patients both in those eligible for screening (ESG, 50–69 years) and those not eligible for screening (NESG, ≥70 years). Local and systemic therapies in different subtypes as well as overall survival (OS) were analyzed.

Results

2171 patients (62.7%) pertained to the ESG and 1292 patients (37.3%) referred to the NESG. The distribution of the common subtypes Luminal A, Luminal B, HER2-like, and Basal-like was comparable in both groups. Treatment varied considerably with less systemic therapies in all subtypes in patients in the NESG. Regarding local therapies, patients in the NESG also received less surgery and less radiotherapy. As to Luminal A patients, best OS was seen in patients receiving endocrine therapy (ET) (7-year OS of 95.6%) and CHT plus ET (7-year OS of 93.1%) in the ESG. In the NESG, best OS was seen in patients receiving CHT plus ET (7-year OS of 95.2%), whereas patients receiving only ET had a 7-year OS of 73.9%.

Conclusions

Despite similar tumor biology, elderly patients are undertreated regarding both systemic and local therapies compared to younger patients, leading to reduced OS.

Trastuzumab in Human Epidermal Growth Factor Receptor 2-Positive Early Breast Cancer: Results of a Prospective, Noninterventional Study on Routine Treatment Between 2006 and 2012 in Germany

PURPOSE

Trastuzumab is part of the standard treatment in patients with human epidermal growth factor receptor 2-positive early breast cancer in addition to (neo)adjuvant chemotherapy. This German prospective noninterventional study, which included major patient cohorts underrepresented in the pivotal randomized studies, examined the generalizability of the results of those studies.

PATIENTS AND METHODS

Between 2006 and 2012, 4,027 patients were enrolled and treated with trastuzumab; they were unselected regarding age or concomitant/sequential adjuvant chemotherapy. Long-term outcome data were obtained in yearly intervals. All analyses were descriptive in nature.

RESULTS

Among 3,940 evaluable patients, 26% were elderly (older than 65 years of age). More than half of the population had pN0 tumor stage. Ninety-four percent received chemotherapy: 78% as adjuvant treatment and 14% as neoadjuvant treatment, 2% both. Anthracyclines were administered in 87% and taxanes in 66%. Trastuzumab was stopped prematurely in 9% (because of cardiotoxicity in 3.5%). Recurrence-free survival was 90.0% (95% confidence interval [CI], 88.9%-91.1%) and 82.8% (95% CI, 81.2%-84.4%) after 3 and 5 years, respectively. The corresponding figures for overall survival were 96.8% (95% CI, 96.1%-97.6%) and 90.0% (95% CI, 88.6%-91.4%). Pathological primary tumor size, lymph node involvement, and hormone receptor status had the greatest independent effect on recurrence risk. Cardiac function toxicity of National Cancer Institute common toxicity criteria grade ≥2 and ≥3 was observed in 2.5% and less than 1% of patients, respectively.

CONCLUSION

The maturing follow-up data seem to confirm the beneficial results of trastuzumab treatment for early breast cancer from the randomized studies. Moreover, these findings support use of trastuzumab-based therapy in patients groups less commonly included in the phase III trials (e.g., elderly patients and those with stage I disease). The Oncologist 2017;22:131-138Implications for Practice: On the basis of the results of large pivotal phase III studies, the inclusion of trastuzumab in adjuvant treatment regimens for human epidermal growth factor receptor 2-positive breast cancer is standard of care. However, in these trials, elderly patients, those with comorbidities, and/or those with contraindications or refusal of cytotoxic chemotherapy are typically underrepresented. This study provides data on observed treatment options, outcomes, and risks in a wider, unselected patient population (including more than 1,000 patients with stage I disease), treated routinely in several institutions of varying size and location across Germany.

Hormone Receptor/Human Epidermal Growth Factor Receptor 2-positive breast cancer: Where we are now and where we are going

Near 75% of all breast cancers (BC) express estrogen receptors (ER) and/or progesterone receptors (PgR), while up to 20% of BC show an overexpression/amplification of Human Epidermal Growth Factor Receptor 2 (HER2). Around 50% of all HER2-overexpressing BC show the coexistence of both HER2 overexpression/amplification and ER and/or PgR overexpression. Numerous in vitro and in vivo studies suggest the existence of a cross-talk between their downstream pathways, which seem to affect the natural history, response to therapy and outcome of patients affected by this subset of BC. Meta-analyses or subgroup analysis of numerous neo-/adjuvant trials demonstrated significant clinical implications deriving from ER/HER2 co-existence, consisting in a different pattern of relapse and dissimilar outcome in response to anti-HER2 therapy. However, only two randomized trials in early disease and three in advanced disease specifically addressed the issue whether a combined approach with both hormonal and anti-HER2 therapy would have a better therapeutic impact in this subset of BC compared to the lone anti-HER2 or hormonal therapies (HT). None of these trials demonstrated improvements in overall survival, even though several efficacy end-points such as progression free survival, in advanced setting, or pCR rates in neoadjuvant setting, often favored the combined hormonal and anti-HER2 therapeutic approach. In the next few years, a certain number of ongoing randomized trials, both in neoadjuvant and advanced setting, will evaluate the efficacy of new anti-HER2 drugs, T-DM1 and pertuzumab, in combination with HT, helping to improve the therapeutic strategy for this specific subtype of breast tumors.

Neratinib after trastuzumab-based adjuvant therapy in patients with HER2-positive breast cancer (ExteNET): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Neratinib, an irreversible tyrosine-kinase inhibitor of HER1, HER2, and HER4, has clinical activity in patients with HER2-positive metastatic breast cancer. We aimed to investigate the efficacy and safety of 12 months of neratinib after trastuzumab-based adjuvant therapy in patients with early-stage HER2-positive breast cancer.

METHODS

We did this multicentre, randomised, double-blind, placebo-controlled, phase 3 trial at 495 centres in Europe, Asia, Australia, New Zealand, and North and South America. Eligible women (aged ≥18 years, or ≥20 years in Japan) had stage 1-3 HER2-positive breast cancer and had completed neoadjuvant and adjuvant trastuzumab therapy up to 2 years before randomisation. Inclusion criteria were amended on Feb 25, 2010, to include patients with stage 2-3 HER2-positive breast cancer who had completed trastuzumab therapy up to 1 year previously. Patients were randomly assigned (1:1) to receive oral neratinib 240 mg per day or matching placebo. The randomisation sequence was generated with permuted blocks stratified by hormone receptor status (hormone receptor-positive [oestrogen or progesterone receptor-positive or both] vs hormone receptor-negative [oestrogen and progesterone receptor-negative]), nodal status (0, 1-3, or ≥4), and trastuzumab adjuvant regimen (sequentially vs concurrently with chemotherapy), then implemented centrally via an interactive voice and web-response system. Patients, investigators, and trial sponsors were masked to treatment allocation. The primary outcome was invasive disease-free survival, as defined in the original protocol, at 2 years after randomisation. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00878709.

FINDINGS

Between July 9, 2009, and Oct 24, 2011, we randomly assigned 2840 women to receive neratinib (n=1420) or placebo (n=1420). Median follow-up time was 24 months (IQR 20-25) in the neratinib group and 24 months (22-25) in the placebo group. At 2 year follow-up, 70 invasive disease-free survival events had occurred in patients in the neratinib group versus 109 events in those in the placebo group (stratified hazard ratio 0·67, 95% CI 0·50-0·91; p=0·0091). The 2-year invasive disease-free survival rate was 93·9% (95% CI 92·4-95·2) in the neratinib group and 91·6% (90·0-93·0) in the placebo group. The most common grade 3-4 adverse events in patients in the neratinib group were diarrhoea (grade 3, n=561 [40%] and grade 4, n=1 [<1%] vs grade 3, n=23 [2%] in the placebo group), vomiting (grade 3, n=47 [3%] vs n=5 [<1%]), and nausea (grade 3, n=26 [2%] vs n=2 [<1%]). QT prolongation occurred in 49 (3%) patients given neratinib and 93 (7%) patients given placebo, and decreases in left ventricular ejection fraction (≥grade 2) in 19 (1%) and 15 (1%) patients, respectively. We recorded serious adverse events in 103 (7%) patients in the neratinib group and 85 (6%) patients in the placebo group. Seven (<1%) deaths (four patients in the neratinib group and three patients in the placebo group) unrelated to disease progression occurred after study drug discontinuation. The causes of death in the neratinib group were unknown (n=2), a second primary brain tumour (n=1), and acute myeloid leukaemia (n=1), and in the placebo group were a brain haemorrhage (n=1), myocardial infarction (n=1), and gastric cancer (n=1). None of the deaths were attributed to study treatment in either group.

INTERPRETATION

Neratinib for 12 months significantly improved 2-year invasive disease-free survival when given after chemotherapy and trastuzumab-based adjuvant therapy to women with HER2-positive breast cancer. Longer follow-up is needed to ensure that the improvement in breast cancer outcome is maintained.

FUNDING

Wyeth, Pfizer, Puma Biotechnology.

Identification of early breast cancer patient cohorts who may benefit from lapatinib therapy

In resource-constrained environments many patients with human epidermal growth factor receptor 2 (HER2)+ early breast cancer are currently not offered adjuvant anti-HER2 therapy. For patients who might be able to receive the tyrosine kinase inhibitor (TKI) lapatinib (e.g. after patent expiration), it is important to identify subgroups of patients for whom anti-HER2 TKI therapy could be beneficial. To do this, we used data from 2489 patients with centrally confirmed HER2+ disease enrolled in the adjuvant Tykerb Evaluation After Chemotherapy (TEACH) trial, investigating the effect of lapatinib in patients with HER2+ early breast cancer not treated with trastuzumab. We performed subgroup analyses and number-needed-to-treat (NNT) calculations using patient and tumour associated predictors. Hormone receptor negative (HR-) patients on lapatinib had a significantly prolonged disease-free survival (DFS) compared to HR- patients on placebo (hazard ratio 0.64, P=0.003). For patients with HR- disease, starting treatment with lapatinib ≤1 year from diagnosis improved DFS by 12.1% [2.1-22.1] at 2 years and 15.7% [4.1-27.2] at 5 years. Depending on lymph node status and time since diagnosis the NNT for recurrence (at 5 years) was between 5.9 (node positive patients <1 year from diagnosis) and 15.9. These numbers are in range with numbers reported for up-front adjuvant trastuzumab for HR unselected patients (e.g. 15.6 for DFS at 4 years in HERA). In a subgroup analysis of the adjuvant TEACH trial, we show that anti-HER2 monotherapy with a TKI is beneficial as adjuvant therapy in a subgroup of patients. NNT in HER2+ HR- patients are in range with those reported from up-front adjuvant trastuzumab trials.

Relapse profile of early breast cancer according to immunohistochemical subtypes: guidance for patient's follow up?

PURPOSE

To analyze the profile of annual recurrence rate (ARR) of patients with early breast cancer (BC) in Tunisia.

PATIENTS AND METHODS

We classified 293 patients with histologically confirmed early BC relapsing after 1 year of follow up into three subgroups: hormone receptor (HR)+ 'HR' [estrogen receptor (ER)+ or progesterone receptor (PR)+ and human epidermal growth factor receptor 2 (HER2)-], triple negative 'TN' (ER-, PR- and HER2 score 0/1 or fluorescence in situ hybridization (FISH)/chromogenic in situ hybridization negative) and HER2 overexpression 'HER2' (HER2+). ARR was restricted to follow-up contribution of each specified time interval. The HR group was the reference group for comparison.

RESULTS

A higher proportion of patients who were up to 35 years old (18% versus 10%, p = 0.04), and patients with obesity (46% versus 26%, p = 0.045) was seen in the TN group. Median time to relapse (MTR) was shorter in TN and HER2 groups than in HR patients (20 and 29 months compared with 56 months, respectively, p < 0.001). In the HR group, the ARR was 22%, 16% and 10% at 3, 4 and 5 years respectively, becoming less than 3% at 7 years. In the TN group, 71% of patients relapsed during the first 2 years and the ARR declined rapidly to less than 1.5% after 4 years. In the HER2 group, the ARR peaked at 2 years (29%) and decreased significantly to 7% and 3% at 5 and 7 years respectively. Adjuvant trastuzumab delayed the MTR from 24 to 34 months (p = 0.022).

CONCLUSION

The relapse risk in Tunisian patients is higher in young women and patients with HER2+ and TN tumors. A long and close follow up is recommended for patients with HR and HER2. Conversely, we suggest that follow up in patients with TN could be spaced after 4 years (ARR being <1.5% after this period).

Infracentimetric HER-2 positive breast tumours-review of the literature

Breast cancer is the most common malignant neoplasm in the world among women. As a result of the dissemination of population screening programmes, about half of non-metastatic breast cancers are now diagnosed at stage I. 10-15% of T1abN0 tumours over-express human epidermal growth factor (HER-2). These tumours have a globally excellent prognosis, however, treatment with chemotherapy and/or targeted therapy may further improve outcomes in selected cases. In this article, we will review studies with information on prognosis and benefit of adjuvant therapy for T1abN0 HER-2+ breast cancer.

The evolving understanding of small HER2-positive breast cancers: matching management to outcomes

Systemic therapy for small (stage I) HER2-positive breast cancers has long posed a dilemma for clinicians, as the majority of these patients were excluded from the large adjuvant trastuzumab trials. However in the decade since those trials were reported, data have accumulated to suggest that recurrence risk for these small but biologically aggressive tumors is nontrivial. In this review, we summarize data from numerous cohort studies describing the outcomes of small HER2-positive tumors, mostly in the absence of HER2-directed therapy. We then examine the potential impact of HER2-directed treatment in this population, culminating in the recently published prospective study of paclitaxel/trastuzumab therapy. The landscape of next generation anti-HER2 therapies is quickly evolving; a role for some of these agents in the small HER2-positive subpopulation may also be on the horizon.

Hormone receptor status predicts the clinical outcome of human epidermal growth factor 2-positive metastatic breast cancer patients receiving trastuzumab therapy: a multicenter retrospective study

Objectives

Trastuzumab, a humanized monoclonal antibody that binds human epidermal growth factor receptor 2 (HER2), dramatically improves the clinical outcomes of HER2-positive breast cancer. Emerging evidence implied that the clinical behavior and sensitivity to targeted agents in HER2-positive breast cancer differed by hormone receptor (HR) status. The objective of this study was to determine the effect of the HR status on survival benefit of HER2-positive metastatic breast cancer when treated with anti-HER2-targeted therapy in People’s Republic of China.

Methods

Metastatic breast cancer patients with HER2-positive diseases across six cancer centers in People’s Republic of China were retrospectively analyzed in our study. Patients were classified into four groups according to HR/HER2 status and trastuzumab treatment: HER2+/HR+ patients with first-line trastuzumab treatment, HER2+/HR+ patients with no trastuzumab treatment, HER2+/HR− patients with first-line trastuzumab treatment, and HER2+/HR− patients with no trastuzumab treatment. Kaplan–Meier analysis, log-rank test, and multivariate analysis were performed during analysis.

Results

A total of 295 patients were included in the final analysis. The median overall survival was 30 months (95% confidence interval: 27.521–32.479). Among patients with HER2+/HR− disease, significant survival benefit was observed when treated with trastuzumab (30 vs 21 months, P=0.000). However, in patients with HER2+/HR+ disease, trastuzumab administration had a survival improvement trend but no significant statistical differences (36 vs 30 months, P=0.258). In the multivariate analysis, HR status was an independent predictor of overall survival and trastuzumab treatment had significantly decreased risk of death in HER2+/HR− patients (hazard ratio =0.330).

Conclusion

HR status is an independent predictor of overall survival in HER2-positive metastatic breast cancer patients and patients with HER2+/HR− subtype might be associated with more survival benefits when treated with trastuzumab-based regimens.