The HER-2 receptor and breast cancer: ten years of targeted anti-HER-2 therapy and personalized medicine

Serum follicle-stimulating hormone level is associated with human epidermal growth factor receptor type 2 and Ki67 expression in post-menopausal females with breast cancer

The present study aimed to determine the association between levels of the gender hormones, follicle-stimulating hormone (FSH), luteinizing hormone (LH), progesterone (P) and prolactin (PRL), and two breast cancer molecular markers, human epidermal growth factor receptor 2 (Her-2) and Ki67, in post-menopausal patients with breast cancer. A retrospective study of the serum hormone levels of FSH, LH, P and PRL and the expression status of Her-2 and Ki67 was performed using 187 post-menopausal females with breast cancer. Her-2⁺ breast cancer patients exhibited higher serum FSH levels compared with Her-2⁻ patients (69.47±3.219 vs. 58.56±1.516 IU/l). The patients with high Ki67 expression [immunohistochemistry (IHC), 3+] displayed higher FSH (72.51±4.616 vs. 60.53±1.476 IU/l) and LH (32.33±1.916 vs. 26.98±0.8852 IU/l) levels than those with lower Ki67 expression. No correlation was identified between the FSH, LH, P and PRL hormone levels, tumor stages and lymphovascular invasion (LVI). In conclusion, a higher serum FSH level was identified in Her-2⁺ post-menopausal patients with breast cancer. Higher serum FSH and LH levels were also observed in breast cancer patients with high Ki67 expression. FSH and LH may function in the progression of breast cancer.

Pertuzumab: a new targeted therapy for HER2-positive metastatic breast cancer

Trastuzumab, a humanized monoclonal antibody, has become an important targeted therapy for patients with all stages of human epidermal growth factor receptor-2 (HER2)-positive breast cancer. However, primary and acquired resistance to trastuzumab remains a significant problem. Pertuzumab, a humanized monoclonal antibody that binds to a domain of the HER2 receptor separate from trastuzumab, may have the potential to overcome trastuzumab resistance. Clinical trials have shown that pertuzumab can be effectively combined with other biologic therapy or chemotherapy in patients with metastatic HER2-positive breast cancer. Pertuzumab is relatively well tolerated with minimal increases in hematologic and cardiac toxicity observed when added to trastuzumab and/or docetaxel. In addition to becoming the standard of care in combination with docetaxel and trastuzumab in patients with newly diagnosed HER2-positive metastatic breast cancer, clinical trials continue to evaluate pertuzumab in combination with other targeted therapy, chemotherapy, and in patients with early stage breast cancer. These trials will help to further determine the role of pertuzumab in the treatment of HER2-positive breast cancer.

Overexpression of CARM1 in breast cancer is correlated with poorly characterized clinicopathologic parameters and molecular subtypes

BACKGROUND

Coactivator-associated arginine methyltransferase 1 (CARM1) belongs to the protein arginine methyltransferase family. CARM1 has been reported to be associated with high grade tumors in breast cancer. It still remains unknown the expression pattern of CARM1 in breast cancer and its relationships with clinicopathological characteristics and molecular subtypes.

METHODS

Two hundred forty-seven invasive breast cancer cases were collected and prepared for tissue array. There were thirty-seven tumors with benign glandular epithelium adjacent to the tumors among these cases. Molecular subtype and CARM1 expression were investigated using immunohistochemistry.

RESULTS

Cell staining was observed in the cytoplasm and/or nucleus. Staining for CARM1 was significantly stronger in adenocarcinoma compared with adjacent benign epithelium. There is a significant correlation between CARM1 overexpression with young age, high grade, estrogen receptor (ER) and progesterone receptor (PR) negative, increased p53 expression, and high Ki-67 index. Our study demonstrated CARM1 overexpression was associated with an increase in the protein expression of HER2. Furthermore, our data indicated CARM1-overexpression rate were remarkably higher in HER2 subtype (69.6%), luminal B subtype (59.6%) and TN subtype (57.1%) compared with luminal A subtype (41.3%).

CONCLUSIONS

CARM1 expression was increased in invasive breast cancer. CARM1 overexpression was associated with poorly characterized clinicopathologic parameters and HER2 overexpression. There were significant differences between different molecular subtypes in their relationship to CARM1 overexpression. Our results support the value of using CARM1 in prognostic stratification of breast cancer patients and its potential therapeutic implications in targeting treatment.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4116338491022965.

Chromosome 17 polysomy: correlation with histological parameters and HER2NEU gene amplification

Aims

HER2NEU gene amplification is present in the majority of invasive breast carcinomas that have HER2 protein overexpression. A subset of breast cancers harbour an increased chromosome 17 (CEP17) copy number (polysomy 17). We investigated the clinicopathologic significance of polysomy 17 in correlation with various histological parameters and HER2NEU gene amplification.

Methods

We collected the surgical specimens of 266 consecutive cases of primary invasive breast carcinomas. HER2NEU gene status and CEP17 copy numbers were assessed by fluorescent in situ hybridisation (FISH). Chromosome 17 polysomy was determined by the presence of ≥3 average CEP17 signals per nucleus.

Results

63 tumours (23.7%) harboured polysomy 17. Carcinomas with polysomy 17 were associated with adverse histological indicators including high histological grade, high nuclear grade, poor Nottingham Prognostic Index, advanced local tumour extent and progesterone receptor negativity. Polysomy 17 was common to HER2NEU amplified and unamplified tumours, and more frequently observed in HER2NEU unamplified (71.4%) cases.

Conclusions

In the absence of the gene amplification, HER2 protein overexpression may be explained by other mechanisms including polysomy 17.

Cardiotoxicity of novel HER2-targeted therapies

BACKGROUND

Trastuzumab, an anti-HER2 humanized monoclonal antibody, is the standard treatment for both early and metastatic HER2-positive breast cancer. In addition to other chemotherapeutic agents, trastuzumab significantly improves response rate and survival in HER2-positive early and metastatic breast cancer. Although it is well known that trastuzumab therapy is closely associated with both symptomatic and asymptomatic cardiotoxicity, less is known about novel HER2-targeted therapies. The aim of this review is to discuss the cardiac safety data from recent studies of novel anti-HER2 drugs other than trastuzumab.

SCOPE

Novel HER2-targeted therapies showed favorable results in HER2 positive metastatic breast cancer patients. Pubmed database, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts were searched until January 2013 using the following search keywords; 'trastuzumab, trastuzumab cardiotoxicity, HER-2 targeted therapies, lapatinib, pertuzumab, trastuzumab emtansine, afatinib and neratinib'; papers which were considered relevant for the aim of this review were selected by the authors. Lapatinib, pertuzumab, T-DM1, neratinib and afatinib molecules are evaluated in the study.

FINDINGS

In a comprehensive analysis, 3689 lapatinib treated patients enrolled in 49 trials; asymptomatic cardiac events were reported in 53 patients (1.4%) and symptomatic grade III and IV systolic dysfunction was observed only in 7 patients (0.2%) treated with lapatinib. In phase I-III trials of pertuzumab, cardiac dysfunction was seen in 4.5-14.5% of patients with pertuzumab treatment and cardiac dysfunction was usually grade I and II. Cardiotoxicity of pertuzumab was usually reported with the trastuzumab combination and no additive cardiotoxicity was reported with addition of pertuzumab to trastuzumab. T-DM1 had a better safety profile compared to trastuzumab, no significant cardiotoxicity was observed with T-DM1 in heavily pre-treated patients. In the EMILIA study, only in 1.7% of patients in the T-DM1 group experienced reduction of left ventricular ejection fraction (LVEF) and grade III LVEF reduction developed only in one patient (0.2%) in the T-DM1 group compared to the lapatinib plus capacitabine group. In phase I-II trials with neratinib no cardiotoxicity was reported whereas cardiotoxicity was seen between 0-5.3% with afatinib treatment.

CONCLUSION

Although cardiac toxicity has been reported as an adverse event for novel HER2-targeted therapies, cardiac dysfunction rate of the novel HER2-targeted therapies is significantly lower than the trastuzumab and combination of these agents with trastuzumab did not significantly increase the cardiac adverse events.

Comparison of subcutaneous and intravenous administration of trastuzumab: a phase I/Ib trial in healthy male volunteers and patients with HER2-positive breast cancer

Trastuzumab is a key component of treatment for human epidermal growth factor receptor 2 (HER2)-positive breast cancer in both the early and metastatic settings. It is administered intravenously, with between 17 and 52 infusions in standard regimens over 1 year. Intravenous administration of trastuzumab requires substantial time commitments for patients and health care professionals and can result in patient discomfort. A subcutaneous formulation of trastuzumab, containing recombinant human hyaluronidase to overcome subcutaneous absorption barriers, would reduce the administration duration and remove the need to establish intravenous access, thus improving the overall convenience of trastuzumab administration. This open-label, 2-part, phase I/Ib study (NCT00800436) was undertaken in healthy male volunteers and female patients with HER2-positive early breast cancer to identify the dose of subcutaneous trastuzumab that resulted in exposure comparable with the approved intravenous trastuzumab dose. A subcutaneous trastuzumab dose of 8 mg/kg was found to result in exposure comparable with the intravenous trastuzumab dose of 6 mg/kg. The subcutaneous formulation was well tolerated, with a trend toward fewer adverse events versus intravenous administration; most adverse events were mild in intensity. These results support an ongoing phase III efficacy and safety study comparing a fixed subcutaneous trastuzumab dose with intravenous trastuzumab administration.

The antibody-drug conjugate: an enabling modality for natural product-based cancer therapeutics

The Antibody Drug Conjugate (ADC) is a therapeutic modality consisting of a monoclonal antibody attached to a cytotoxic, small-molecule payload. The antibody portion of the ADC serves as a transport vehicle that recognizes and binds to a protein antigen expressed in tumor tissues. The localized delivery and release of the payload within or near malignant cells allows for targeted delivery of a potent cytotoxic agent to diseased tissue, while reducing damage to antigen-negative, normal tissues. Recent years have witnessed an explosive increase in ADC-based therapies, due mainly to clinical reports of activity in both hematologic and epithelial cancers. Accompanying this upsurge in ADC development is a renewed interest in natural product cytotoxins, which are typically highly potent cell-killing agents, but suffer from poor drug-like properties and narrow safety margins when systemically administered as conventional chemotherapeutics. In this review, we discuss recent advances related to the construction of ADCs, the optimization of ADC safety and efficacy, and the increasingly pivotal roles of natural product payloads in the current and future landscape of ADC therapy.

Use of pertuzumab for the treatment of HER2-positive metastatic breast cancer

INTRODUCTION

Targeting the human epidermal growth factor receptor (HER) family of tyrosine kinase receptors has proven to be effective as a therapeutic strategy for HER type 2 (HER2)-positive breast cancer. Since resistance to trastuzumab occurs relatively frequently, particularly in the metastatic setting, novel anti-HER2 targeted therapies with complementary and/or synergistic mechanisms of action have been under development. Pertuzumab, a HER2-targeted monoclonal antibody that prevents HER2 dimerisation, is the first of a class of promising targeted agents for the treatment of HER2-positive breast cancer.

METHODS

A review of the biomedical literature published prior to February 2013 was conducted in English using PubMed. ClinicalTrials.gov was searched for appropriate clinical trials. The search terms used included breast neoplasm, pertuzumab, dimerisation, and HER2-positive. Abstracts of studies presented at the ASCO and ESMO Annual Meetings, and San Antonio Breast Cancer Symposium were also included.

RESULTS

Pertuzumab represents a novel anti-HER2 targeted therapy for HER2-positive breast cancers. In this article, we describe the mechanism of action of pertuzumab, as well as its drug development process and preclinical testing results. Based on the results of ancillary studies, dual inhibition using pertuzumab and trastuzumab was shown to be effective for the management of HER2-positive metastatic breast cancers pre-treated with trastuzumab-based therapy. For the first-line setting, the combination of both pertuzumab and trastuzumab with docetaxel (CLEOPATRA trial; clinical evaluation of pertuzumab and trastuzumab) has changed the paradigm of patient management.

CONCLUSION

Pertuzumab provided a more comprehensive inhibition of HER2-driven signalling pathways. When administered together with trastuzumab, pertuzumab represent a significant advancement for the treatment of HER2-positive metastatic breast cancer patients.

Genetic heterogeneity in breast cancer: the road to personalized medicine?

More women die from breast cancer across the world today than from any other type of malignancy. The clinical course of breast cancer varies tremendously between patients. While some of this variability is explained by traditional clinico-pathological factors (including patient age, tumor stage, histological grade and estrogen receptor status), molecular profiling studies have defined breast cancer subtypes with distinct clinical outcomes. This mini-review considers recent studies which have used genomics technologies in an attempt to identify new biomarkers of prognosis and treatment response. These studies highlight the genetic heterogeneity that exists within breast cancers in space and time.

Assessing the potential cost-effectiveness of retesting IHC0, IHC1+, or FISH-negative early stage breast cancer patients for HER2 status

BACKGROUND

Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) tests are commonly used to assess human epidermal growth factor 2 (HER2) status of tumors in patients with breast cancer. This analysis evaluates the likely cost-effectiveness of expanded retesting to assess HER2 tumor status in women with early stage breast cancer.

METHODS

We developed a decision-analytic model to estimate the incremental cost-effectiveness ratio (ICER) of expanded reflex testing from a US payer perspective. Expanded reflex testing is defined as retesting tumor specimens from patients whose tumors are IHC0, IHC1+, or FISH-negative on their first test. In the base case, we assumed that 80% of patient tumors are initially IHC-tested and 20% are FISH-tested. Testing outcomes for IHC and FISH with and without retesting were based on published meta-analyses. The cost of tests and treatment and the long-term health outcomes were obtained from the literature.

RESULTS

In the base case, we estimated that 2.27% of women who received expanded reflex testing would be HER2-positive and receive trastuzumab treatment: the projected ICER was $36,721 per life year or $39,745 per quality-adjusted life year (QALY). This varied between $47,100 per QALY and $35,500 per QALY if we assumed that 1%-8% of patients retested were then HER2+, respectively. The results of deterministic and probabilistic sensitivity analysis were robust. This strategy would result in 4700 (2000-17,000) patients being eligible to receive trastuzumab treatment annually.

CONCLUSIONS

Retesting patients who are IHC0, IHC1+, or FISH-negative is projected to be a cost-effective clinical strategy.

Human epidermal growth factor receptor 2-positive breast cancer: which cytotoxic agent best complements trastuzumab's efficacy in vitro?

INTRODUCTION

Despite trastuzumab having enhanced selectivity for human epidermal growth factor receptor 2 (HER-2) overexpressing breast cancer cells, treatment is hampered by interindividual variation and tumors with high mitogenic potential. The lack of significant clinical benefit in certain patient cohorts suggests that HER-2 expression is ineffective as a sole prognostic indicator of response to therapy. Therefore, optimizing the clinical role of trastuzumab in drug combinations remains critical for clinical success.

AIM

To investigate the effects of trastuzumab in combination with either doxorubicin or geldanamycin on in vitro cell viability, cell cycling, apoptosis and relative HER-2 expression in HER-2-positive (SK-BR-3) and estrogen receptor-positive (MCF-7) breast adenocarcinoma models.

RESULTS

HER-2-rich SK-BR-3 cells demonstrated a greater sensitivity to the effects of doxorubicin than MCF-7 cells. Concurrent trastuzumab exposure resulted in a further reduction in cell viability. This decreased cell viability induced by doxorubicin was associated with activation of executioner caspases as well as with alterations in cell-cycle kinetics, primarily promoting S-phase accumulation. Doxorubicin had no effect on surface HER-2 density expression. Geldanamycin reduced cell viability significantly greater in SK-BR-3 than MCF-7 cells, and was associated with G2 cell-cycle accumulation. The addition of trastuzumab did not augment these effects. Geldanamycin promoted substantial reductions in relative surface HER-2 density in SK-BR-3 cells.

CONCLUSION

The in vitro data supported the rationale for using doxorubicin in trastuzumab-based therapies. Therefore, despite the incidence of cardiotoxicity, doxorubicin could retain a fundamental role in treating HER-2-positive breast cancer. While geldanamycin is a potent cytotoxic agent, its concurrent use with trastuzumab requires further research into the transient or permanent nature of alterations in HER-2 status in cell progeny.

Bringing cancer serological diagnosis to a new level: focusing on HER2, protein ectodomain shedding and neoepitope technology

Cancer is a heterogeneous disease and consequently an exact diagnosis is as important as the actual therapy. Therefore, identification of novel diagnostic biomarker targets is urgently needed. Physiological and pathological changes are reflected by post-translational modifications of proteins. Each post-translational modification (e.g., proteolytic cleavage) is the result of a specific local process and may produce disease-specific neoepitopes. Neoepitopes have been successfully used as biomarkers in many diseases, and may also serve as promising tools in the development of future diagnostic assays within oncology. By specifically targeting neoepitopes, more information regarding disease-type and -state may be obtained and future research into neoepitopes will provide important and novel means for the diagnosis, prognosis and treatment efficacy in cancer. In this paper, we focus on protein ectodomain shedding and the generation of neoepitopes as future noninvasive (serological) cancer biomarkers. We use the protein ectodomain shedding of the human epidermal growth factor receptor 2, which is associated with breast cancer, as an example. We assess the current status of measuring human epidermal growth factor receptor 2 and discuss how this potentially could be improved. Furthermore, we expand the discussion to include examples of other cancer associated proteins.

HER3 status by immunohistochemistry is correlated with poor prognosis in hormone receptor-negative breast cancer patients

Breast cancer is a highly heterogeneous malignancy. The triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2 (HER2) breast cancer subtypes are highly aggressive and are associated with a poor prognosis. The therapeutic targets for TNBC remain undefined, and many patients with the HER2 subtype acquire resistance to therapy after prolonged treatment. The objective of this study was to evaluate the prognostic significance of HER3 expression in invasive breast carcinoma. We established matched tissue microarray (TMA) blocks and clinical data from 950 cases of invasive breast carcinoma with long-term clinical follow-up data (median 109.7 months). Using the TMAs, we characterized the expression of ER, PR, HER2, EGFR, and HER3 by immunohistochemistry. Each case was classified as one of four IHC-based subtypes based on the expression of hormonal receptor (HR) and HER2. The clinicopathological characteristics and survival of 950 patients were analyzed by subtype. In the TNBC subtype, the HER3(+) group showed poorer disease-free survival (DFS, P = 0.010) and overall survival (OS, P = 0.015) than the HER3(-) group. In the HER2 subtype, the HER3(+) group also showed poorer DFS (P = 0.022) and OS (P = 0.077) than the HER3(-) group. However, there was no difference in patients with HR-positive breast cancer. HER3 expression was associated with poor DFS in both the TNBC and HER2 subtypes and poor OS in the TNBC subtype. HER3 overexpression is an important prognostic marker in hormone receptor-negative breast cancer, and further study is needed to clarify the role of HER-3 targeted treatment.

Neoadjuvant Treatment in Patients with HER2-Positive Breast Cancer

Approximately 20%-25% of patients with breast cancer demonstrate amplification of the human epidermal receptor type 2 (HER2) gene, resulting in an overexpression of the HER2 receptor. This overexpression is associated with aggressive disease, relatively poor prognosis, and worse clinical outcomes. Neoadjuvant therapy is the standard treatment in patients with locally advanced, inflammatory, or inoperable primary breast cancer. It is generally used to downstage the tumors and therefore to improve surgical options including breast-conserving surgery rather than mastectomy. It has been confirmed that patients with pathological complete response (pCR) to neoadjuvant treatment have better disease-free survival (DFS) and overall survival (OS). Neoadjuvant treatment can also serve as in vivo test of sensitivity to the used therapeutic regimen. The preferred neoadjuvant approach to patients with HER2-positive breast cancer is a sequential anthracycline-taxane-based chemotherapy in combination with trastuzumab. Addition of other anti-HER2 agents has increased pCR rate up to 75% and will probably become a new therapeutic direction. In the first part of this paper, we summarize the information about HER2-positive breast cancer, the various treatment possibilities, and the results of the major neoadjuvant trials. The second part focuses on the data concerning the importance of pCR and the potential risk of cardiotoxicity associated with this treatment.

Efficacy, safety, pharmacokinetics and biomarker findings in patients with HER2-positive advanced or metastatic breast cancer treated with lapatinib in combination with capecitabine: results from 51 Japanese patients treated in a clinical study

Background

The results from a phase III trial conducted outside of Japan demonstrated a significant improvement in time to progression (TTP) when lapatinib was combined with capecitabine compared with capecitabine alone in patients with HER2-positive advanced or metastatic breast cancer. In this clinical study of lapatinib in combination with capecitabine, efficacy, safety, pharmacokinetics (PK) and biomarkers were investigated in Japanese patients with HER2-positive advanced or metastatic breast cancer treated with prior trastuzumab.

Methods

Eligible women received lapatinib 1250 mg once daily and capecitabine 1000 mg/m² twice daily on days 1 through 14 of a 21-day cycle. The primary endpoint was the clinical benefit rate (CBR: complete response, partial response or stable disease for at least 24 weeks).

Results

Lapatinib in combination with capecitabine was well tolerated in the 51 patients enrolled in this study. CBR was 59 % (95 % CI 44.2, 72.4), and the median TTP in the Kaplan-Meier estimate was 36 weeks (95 % CI 27.1, 48.0). The majority of drug-related adverse events were mild to moderate (grade 1 or 2); the most common adverse events reported were palmar-plantar erythrodysesthesia syndrome (76 %), diarrhea (67 %) and stomatitis (41 %).

Conclusions

Lapatinib in combination with capecitabine in Japanese HER2-positive breast cancer patients was well tolerated. Overall, our findings on the efficacy, safety and PK were similar to those reported from the overseas studies.

Companion biomarkers: paving the pathway to personalized treatment for cancer

BACKGROUND

Companion biomarkers are biomarkers that are used in combination with specific therapies and that prospectively help predict likely response or severe toxicity. In this article we review the role of companion biomarkers in guiding treatment in patients with cancer.

CONTENT

In addition to the established companion biomarkers such as estrogen receptors and HER2 (human epidermal growth factor receptor 2) in breast cancer, several new companion biomarkers have become available in recent years. These include v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations for the selection of patients with advanced colorectal cancer who are unlikely to benefit from anti-epidermal growth factor receptor antibodies (cetuximab or panitumumab), epidermal growth factor receptor (EGFR) mutations for selecting patients with advanced non-small cell lung cancer (NSCLC) for treatment with tyrosine kinase inhibitors (gefitinib or erlotinib), v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations for selecting patients with advanced melanoma for treatment with anti-BRAF agents (vemurafenib and dabrafenib), and anaplastic lymphoma receptor tyrosine kinase (ALK) translocations for identifying patients with NSCLC likely to benefit from crizotinib.

SUMMARY

The availability of companion biomarkers should improve drug efficacy, decrease toxicity, and lead to a more individualized approach to cancer treatment.

Effectiveness of neoadjuvant trastuzumab and chemotherapy in HER2-overexpressing breast cancer

Purpose

Trastuzumab and chemotherapy is the current standard of care in HER2+ early or locally advanced breast cancer, but there are scanty literature data of its real world effectiveness.

Methods

We retrospectively reviewed 205 patients with HER2+ breast cancer diagnosed in 10 Italian Medical Oncology Units between July 2003 and October 2011. All patients received neoadjuvant systemic therapy (NST) with trastuzumab in association with chemotherapy. Many different chemotherapy regimens were used, even if 90 % of patients received schemes including anthracyclines and 99 % received taxanes. NST was administered for more than 21 weeks (median: 24) in 130/205 (63.4 %) patients, while trastuzumab was given for more than 12 weeks (median: 12 weeks) in 101/205 (49.3 %) patients. pCR/0 was defined as ypT0+ypN0, and pCR/is as ypT0/is+ypN0.

Results

pCR/0 was obtained in 24.8 % and pCR/is in 46.8 % of the patients. At multivariate logistic regression, nonluminal/HER2+ tumors (P < 0.0001) and more than 12 weeks of neoadjuvant trastuzumab treatment (P = 0.03) were independent predictors of pCR/0. Median disease-free survival (DFS) and cancer-specific survival (CSS) have not been reached at the time of analysis. At multivariate analysis, nonluminal/HER2+ subclass (DFS: P = 0.01 and CSS: P = 0.01) and pathological stage II–III at surgery (DFS: P < 0.0001 and CSS: P = 0.001) were the only variables significantly associated with a worse long-term outcome.

Conclusions

Our data set the relevance of molecular subclasses and residual tumor burden after neoadjuvant as the most relevant prognostic factors for survival in this cohort of patients.

Pertuzumab, trastuzumab, and docetaxel for HER2-positive metastatic breast cancer (CLEOPATRA study): overall survival results from a randomised, double-blind, placebo-controlled, phase 3 study

BACKGROUND

CLEOPATRA is a phase 3 study to compare the efficacy and safety of pertuzumab, trastuzumab, and docetaxel with placebo, trastuzumab, and docetaxel in patients with HER2-positive first-line metastatic breast cancer. The results of the primary analysis showed significantly longer median progression-free survival in the pertuzumab group than in the placebo group. Interim analysis of overall survival favoured the pertuzumab group but was not significant. Here, we report results for overall survival after an additional year of follow-up.

METHODS

The study was a double-blind randomised trial undertaken at 204 centres in 25 countries. Patients with HER2-positive metastatic breast cancer who had not received previous chemotherapy or biological treatment for their metastatic disease were randomly assigned to receive either pertuzumab, trastuzumab, and docetaxel (n=402) or the same regimen with a matching placebo replacing pertuzumab (n=406). Randomisation was in a 1:1 ratio, stratified by geographical region and previous treatment status. The primary endpoint was progression-free survival (assessed independently), which has been reported previously; no follow-up data were gathered for the primary endpoint. Secondary endpoints included overall survival, progression-free survival (assessed by investigator), objective response rate, and safety. Median follow-up was 30 months in both groups. Efficacy endpoints were analysed in the intention-to-treat population and safety was analysed by treatment received. The study is completed but safety and survival data continue to be followed up. This trial is registered with ClinicalTrials.gov, number NCT00567190.

FINDINGS

In the intention-to-treat population, 267 patients died by data cutoff (May 14, 2012), 154 (38%) of 406 in the placebo group and 113 (28%) of 402 in the pertuzumab group. Median overall survival was 37.6 months (95% CI 34.3-NE [not estimable]) in the placebo group but had not been reached (95% CI 42.4-NE) in the pertuzumab group (hazard ratio 0.66, 95% CI 0.52-0.84; p=0.0008). Investigator-assessed median progression-free survival was 12.4 months (95% CI 10.4-13.5) in the placebo group and 18.7 months (16.6-21.6) in the pertuzumab group (hazard ratio 0.69, 95% CI 0.58-0.81). Serious adverse events were reported in 115 (29%) of 396 patients who received placebo, trastuzumab, and docetaxel and 148 (36%) of 408 who received pertuzumab, trastuzumab, and docetaxel, and included febrile neutropenia, neutropenia, diarrhoea, pneumonia, and cellulitis. Overall, adverse events were similar to those reported at the primary analysis with respect to frequency, severity, and specificity.

INTERPRETATION

Our analysis shows a significant improvement in overall survival with pertuzumab, trastuzumab, and docetaxel in patients with HER2-positive metastatic breast cancer, compared with placebo, trastuzumab, and docetaxel. Since this effect was not achieved at the expense of adverse events, this regimen represents a substantial improvement on the standard of care for this population of patients.

FUNDING

F Hoffmann-La Roche, Genentech.

Relapsed classic E-cadherin (CDH1)-mutated invasive lobular breast cancer shows a high frequency of HER2 (ERBB2) gene mutations

PURPOSE

We queried whether comprehensive genomic profiling using a next-generation sequencing-based assay could identify novel and unanticipated targets of therapy for patients with relapsed invasive lobular carcinoma (ILC).

EXPERIMENTAL DESIGN

DNA sequencing (Illumina HiSeq 2000) was conducted for 3,320 exons of 182 cancer-related genes and 37 introns of 14 genes frequently rearranged in cancer on indexed, adaptor-ligated, hybridization-captured libraries using DNA isolated from formalin-fixed paraffin-embedded sections from 22 histologically verified ILC.

RESULTS

A total of 75 genomic alterations were identified with an average of 3.4 alterations per tumor (range, 1-6), of which 35 were actionable for an average of 1.59 actionable alterations per patient (range, 0-3). Nineteen of 22 (86%) of the ILC samples harbored at least one actionable alteration. Six (27%) cases featured alterations in ERRB2 including 4 (18%) with ERBB2 mutation, 1 (5%) with an ERBB2 gene fusion, and 1 (5%) with an ERBB2 copy number gain (amplification). The enrichment of ERBB2 mutations/fusion in CDH1-mutated ILC (5 of 22, 23%) compared with the 5 ERBB2 mutations in a series of 286 non-CDH1-mutated breast cancers from which the ILC cases were obtained (5 of 286, 2%) was significant (P = 0.0006).

CONCLUSIONS

Comprehensive genomic profiling of relapsed CDH1-mutated ILC revealed actionable genomic alterations in 86% of cases, featured a high incidence of ERBB2 alterations, and can reveal actionable alterations that can inform treatment decisions for patients with ILC.

HER2-positive breast cancer patients receiving trastuzumab treatment obtain prognosis comparable with that of HER2-negative breast cancer patients

PURPOSE

The efficacy of trastuzumab in Chinese breast cancer (BC) patients has rarely been reported. This study was designed to compare the clinical outcomes of HER2-positive BC patients receiving or not receiving trastuzumab treatment and HER2-negative BC patients.

PATIENTS AND METHODS

This study involved three groups of patients. The first group was 115 human epidermal growth factor receptor 2 (HER2)-positive BC patients treated with trastuzumab who were enrolled at Sun Yat-sen University Cancer Center between January 2002 and July 2010; the second group was a matched control group of 115 HER2-positive patients who did not receive trastuzumab treatment; the third group was a matched group of 115 HER2-negative patients who received conventional therapy in the adjuvant setting. The primary endpoint was 3-year and 5-year disease-free survival (3-DFS and 5-DFS, respectively). The Kaplan-Meier method, log-rank test, and multivariate Cox proportional hazard regression model were used for survival analysis. The differences in survival rates among the three groups were also analyzed according to two different periods: 2002-2006 and 2007-2010.

RESULTS

The median duration of follow-up was 36 months (range, 12-111 months). The 3-DFS rates in the HER2-negative group, the HER2-positive group who received trastuzumab treatment, and the HER2-positive group who did not receive trastuzumab treatment were 82.6%, 89.6%, and 67.0%, respectively. The 3-DFS rate for the total study population was statistically significant (P < 0.001). Further analysis indicated a statistically significant difference in 3-DFS between either of the first two groups and the third group (P < 0.01), but the difference between the first two groups was not statistically significant (P = 0.157). Among the three groups, the 3-DFS rates during 2002-2006 did not have a significant difference compared with that during 2007-2010.

CONCLUSION

This study has further confirmed the efficacy of trastuzumab for HER2-positive operable BC in Chinese patients. It has also demonstrated that the 3-DFS and 5-DFS rates between HER2-positive patients receiving trastuzumab treatment and HER2-negative patients are comparable.

mTOR inhibitors in advanced breast cancer: ready for prime time?

Current therapeutic approaches for advanced breast cancer frequently target receptors mediating cell survival and proliferation, such as the estrogen receptor and/or progesterone receptor and human epidermal growth factor receptor-2. Although these approaches are effective for many patients, treatment resistance is common. Therefore, new treatment approaches are needed for patients with advanced breast cancer. Mammalian target of rapamycin is a highly conserved serine-threonine kinase that acts as a major signaling hub that integrates and synergizes with cellular proliferation, survival, and/or motility signals mediated by estrogen receptor, human epidermal growth factor receptor-2, and other receptor tyrosine kinases. Dysregulation of mammalian target of rapamycin signaling occurs in various tumor types, including breast cancer, and has been associated with cancer pathogenesis, disease progression, and treatment resistance. Recent clinical trials show that combined inhibition of mammalian target of rapamycin and estrogen receptor represents an effective strategy for treating hormone receptor-positive advanced breast cancer progressing on nonsteroidal aromatase inhibitor therapy, and data from ongoing trials combining mammalian target of rapamycin inhibition with human epidermal growth factor receptor-2-targeted therapy are awaited. This review focuses on the molecular rationale underlying strategies to enhance sensitivity to treatment in hormone receptor-positive and human epidermal growth factor receptor-2-positive advanced breast cancer, the clinical efficacy of such approaches, and future perspectives.

The HER2 CISH pharmDx(™) Kit in the assessment of breast cancer patients for anti-HER2 treatment

Testing for amplification of the human EGF receptor 2 (HER2) gene by in situ hybridization is a central principle for the identification of breast cancer patients likely to respond to treatments directed toward HER2. However, its application in clinical routine has been somewhat restricted by the typical use of a visualization system based on fluorescence (FISH), which requires skilled, work-intensive, high-magnification quantitative microscopy. The US FDA has recently approved the HER2 CISH pharmDx™ Kit, which is characterized by employing a chromogenic visualization system that allows quantification of the HER2 gene and centromere 17 reference signals by relatively low-magnification brightfield microscopy. It is indicated as an aid in the assessment of patients for whom Herceptin(®) (trastuzumab) treatment is being considered.

Generation and characterization of new HER2 monoclonal antibodies

Antibodies are among the most commonly used research and diagnostic tools. Antibody type and clonality are important in any assay as they can influence epitope detection. HER2 oncoprotein is overexpressed or undergoes gene amplification in approximately 30% of invasive breast carcinomas and 20% of gastric adenocarcinomas. Overexpression of HER2 is primarily detected by immunohistochemistry (IHC) on neoplastic tissue sections. We produced five murine hybridoma clones secreting monoclonal antibodies (MAbs) against HER2 protein. For hybridoma production, spleen cells from BALB/c mice immunized with a recombinant fragment of the extracellular portion of HER2 (rHER2) were fused to SP2/O-Ag14 cells, selected in HAT medium and screened by indirect ELISA. MAbs secreted were characterized according to isotypes, functional affinity constants, reaction with the native protein in MCF-7 cells by indirect immunofluorescence and in tissue sections from HER2 positive breast cancer specimens by IHC. Two MAbs were IgG2b and three were IgG1, and their affinity constants ranged from 6×10(7) to 1×10(9)M(-1). All MAbs reacted with the native protein and two stained strongly the membrane of neoplastic cells overexpressing HER2. These two MAbs could be useful in assaying HER2 overexpression in human tissues for research and possibly diagnostic purposes after a proper large-scale validation study.

Molecular imaging for monitoring treatment response in breast cancer patients

Currently, tumour response following drug treatment is based on measurement of anatomical size changes. This is often done according to Response Evaluation Criteria in Solid Tumours (RECIST) and is generally performed every 2-3 cycles. Bone metastases, being the most common site of distant metastases in breast cancer, are not measurable by RECIST. The standard response measurement provides no insight in changes of molecular characteristics. In the era of targeted medicine, knowledge of specific molecular tumour characteristics becomes more important. A potential way to assess this is by means of molecular imaging. Molecular imaging can visualise general tumour processes, such as glucose metabolism with (18)F-fluorodeoxyglucose ((18)F-FDG) and DNA synthesis with (18)F-fluorodeoxythymidine ((18)F-FLT). In addition, an increasing number of more specific targets, such as hormone receptors, growth factor receptors, and growth factors can be visualised. In the future molecular imaging may thus be of value for personalised treatment-selection by providing insight in the expression of these drug targets. Additionally, when molecular changes can be detected early during therapy, this may serve as early predictor of response. However, in order to define clinical utility of this approach results from (ongoing) clinical trials is required. In this review we summarise the potential role of molecular imaging of general tumour processes as well as hormone receptors, growth factor receptors, and tumour micro-environment for predicting and monitoring treatment response in breast cancer patients.

Simulating the contribution of a biospecimen and clinical data repository in a phase II clinical trial: A value of information analysis

The potential contributions of a centralized data warehouse or repository in clinical research include the expedited accrual of subjects for phase II trials. Understanding the contribution of data warehouses that integrate clinical, biospecimen, and molecular data for the conduct of clinical trials is essential to inform private and public decisions on resource allocation and investment. We conducted a value of information analysis using data from recent trials at the Moffitt Cancer Center and simulated the potential reductions in trial size due to possible alternative scenarios of expedited accrual. In this study, we compared alternative data sets using a single model to assess value of information. Our findings suggest that the reductions in trial size range from 0% to 43%, depending on the amount of censoring in overall survival. The ability to expedite the accrual of patients for clinical trial studies using large data repositories that store data on inclusion/exclusion criteria and response to standard of care therapies demonstrated significant improvement in reducing the number of subjects needed to achieve similar end-results, as evaluated using value of information analysis with a limited number of parameters and a parsimonious model of overall survival.

HER2 Dimerization Inhibitor Pertuzumab - Mode of Action and Clinical Data in Breast Cancer

The humanized monoclonal antibody pertuzumab prevents the dimerization of HER2 with other HER receptors, in particular the pairing of the most potent signaling heterodimer HER2/HER3, thus providing a potent strategy for dual HER2 inhibition. It binds to the extracellular domain of HER2 at a different epitope than trastuzumab. Pertuzumab and trastuzumab act in a complementary fashion and provide a more complete blockade of HER2-mediated signal transduction than either agent alone. Phase II studies demonstrated that pertuzumab was generally well tolerated as a single agent or in combination with trastuzumab and/or cytotoxic agents, and implied an improved clinical efficacy of the combination of pertuzumab and trastuzumab in early and advanced HER2-positive breast cancer. Results of the pivotal phase III study CLEOPATRA in patients with HER2-positive metastatic breast cancer demonstrated that the addition of pertuzumab to first-line combination therapy with docetaxel and trastuzumab significantly prolonged progression-free and overall survival without increasing cardiac toxicity. Currently, the combination of both antibodies is being explored in the palliative setting as well as in the treatment of early HER2-positive breast cancer. Dual HER2 inhibition with the HER2 dimerization inhibitor pertuzumab and trastuzumab may change clinical practice in HER2-positive first-line metastatic breast cancer treatment.

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

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

Risk assessment, disease prevention and personalised treatments in breast cancer: is clinically qualified integrative approach in the horizon?

Breast cancer is a multifactorial disease. A spectrum of internal and external factors contributes to the disease promotion such as a genetic predisposition, chronic inflammatory processes, exposure to toxic compounds, abundant stress factors, a shift-worker job, etc. The cumulative effects lead to high incidence of breast cancer in populations worldwide. Breast cancer in the USA is currently registered with the highest incidence rates amongst all cancer related patient cohorts. Currently applied diagnostic approaches are frequently unable to recognise early stages in tumour development that impairs individual outcomes. Early diagnosis has been demonstrated to be highly beneficial for significantly enhanced therapy efficacy and possibly full recovery. Actual paper shows that the elaboration of an integrative diagnostic approach combining several levels of examinations creates a robust platform for the reliable risk assessment, targeted preventive measures and more effective treatments tailored to the person in the overall task of breast cancer management. The levels of examinations are proposed, and innovative technological approaches are described in the paper. The absolute necessity to create individual patient profiles and extended medical records is justified for the utilising by routine medical services. Expert recommendations are provided to promote further developments in the field.

Phase II randomized study of trastuzumab emtansine versus trastuzumab plus docetaxel in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer

PURPOSE

Trastuzumab emtansine (T-DM1), an antibody-drug conjugate composed of the cytotoxic agent DM1 conjugated to trastuzumab via a stable thioether linker, has shown clinical activity in single-arm studies enrolling patients with human epidermal growth factor receptor 2 (HER2) -positive metastatic breast cancer (MBC) whose disease had progressed on HER2-targeted therapy in the metastatic setting.

PATIENTS AND METHODS

Patients (N = 137) with HER2-positive MBC or recurrent locally advanced breast cancer were randomly assigned to trastuzumab plus docetaxel (HT; n = 70) or T-DM1 (n = 67) as first-line treatment until disease progression or unacceptable toxicity. Primary end points were investigator-assessed progression-free survival (PFS) and safety. Key secondary end points included overall survival (OS), objective response rate (ORR), duration of objective response, clinical benefit rate, and quality of life.

RESULTS

Median PFS was 9.2 months with HT and 14.2 months with T-DM1 (hazard ratio, 0.59; 95% CI, 0.36 to 0.97); median follow-up was approximately 14 months in both arms. ORR was 58.0% (95% CI, 45.5% to 69.2%) with HT and 64.2% (95% CI, 51.8% to 74.8%) with T-DM1. T-DM1 had a favorable safety profile versus HT, with fewer grade ≥ 3 adverse events (AEs; 46.4% v 90.9%), AEs leading to treatment discontinuations (7.2% v 34.8%), [corrected] and serious AEs (20.3% v 25.8%). Preliminary OS results were similar between treatment arms; median follow-up was approximately 23 months in both arms.

CONCLUSION

In this randomized phase II study, first-line treatment with T-DM1 for patients with HER2-positive MBC provided a significant improvement in PFS, with a favorable safety profile, versus HT.

Testing for her2 in breast cancer: current pathology challenges faced in Canada

This review is designed to highlight several key challenges in the diagnosis of human epidermal growth factor receptor 2 (her2)-positive breast cancer currently faced by pathologists in Canada: Pre-analysis issues affecting the accuracy of her2 testing in non-excision sample types: core-needle biopsies, effusion samples, fine-needle aspirates, and bone metastasesher2 testing of core-needle biopsies compared with surgical specimensCriteria for retesting her2 status upon disease recurrenceLiterature searches for each topic were carried out using the medline, Embase, International Pharmaceutical Abstracts, and biosis databases. In addition, the congress databases of the American Society of Clinical Oncology (2005-2011) and the San Antonio Breast Cancer Symposium (2007-2011) were searched for relevant abstracts.All authors are expert breast pathologists with extensive experience of her2 testing, and several participated in the development of Canadian her2 testing guidelines. For each topic, the authors present an evaluation of the current data available for the guidance of pathology practice, with recommendations for the optimization or improvement of her2 testing practice.

Self-assembled antibody multimers through peptide nucleic acid conjugation

With the recent clinical success of bispecific antibodies, a strategy to rapidly synthesize and evaluate bispecific or higher order multispecific molecules could facilitate the discovery of new therapeutic agents. Here, we show that unnatural amino acids (UAAs) with orthogonal chemical reactivity can be used to generate site-specific antibody-oligonucleotide conjugates. These constructs can then be self-assembled into multimeric complexes with defined composition, valency, and geometry. With this approach, we generated potent bispecific antibodies that recruit cytotoxic T lymphocytes to Her2 and CD20 positive cancer cells, as well as multimeric antibody fragments with enhanced activity. This strategy should accelerate the synthesis and in vitro characterization of antibody constructs with unique specificities and molecular architectures.

Budget impact analysis of the use of oral and intravenous anti-cancer drugs for the treatment of HER2-positive metastatic breast cancer

OBJECTIVES

Two anti-cancer drugs are currently approved for the treatment of HER2-positive metastatic breast cancer (MBC): trastuzumab-based therapy (TBT) administered intravenously as first line therapy until disease progression and lapatinib, an oral self-administered dual therapy with capecitabine (L+C) as second intention for patients who continue to progress despite TBT. In current practice, TBT is still prescribed beyond disease progression. In addition to medical reasons, the difficulty to switch eligible patients to oral drugs may also be explained by economic reasons. Thus, we aimed at comparing the budgetary impact of TBT and L+C for progressing HER2+MBC after TBT from the French Health Insurance perspective.

METHODS

A budget impact analysis was performed on a 3-year time horizon (2012-2014) to simulate a dynamic cohort of 4182 HER2-positive patients with a progressing MBC treated with TBT (73%) and L + C (27%). The model was adjusted on progression-free survival (PFS). Office visits, clinical evaluations, drug acquisition, administration costs, and transportation costs obtained from the literature and published databases were considered.

RESULTS

In the base case analysis (2012), the annual treatment cost per patient for TBT (€36,077) was 2-times higher than that of L + C (€17,165). Using L + C for all patients (n = 4182) would avoid €34.8 million of drug administration and transportation costs. Hospital costs represented 1% vs 88%, while community costs represented 99% vs 12% of L + C and TBT treatment costs, respectively. The lack of direct comparison PFS and treatment dosage modification data were the main limitations. However, no major changes from baseline results were observed from sensitivity analyses.

CONCLUSIONS

Despite a slightly higher acquisition cost, the treatment cost of L + C remains lower than that of TBT, and it is the only approved anti-HER2 treatment for HER2-positive patients with progressing MBC. Based on this, it seems important to consider the potential savings for Health Insurance with the use of oral drug due to the reduction of outpatient hospitalizations. Such reductions may result in a subsequent budget reduction for hospitals, but may also provide those facing acute medical activity with opportunities to better manage other diseases whose treatment cannot be externalized.

When Standard Therapy Fails in Breast Cancer: Current and Future Options for HER2-Positive Disease

The area of HER2-positive breast cancer is a rapidly changing field. The use of the humanized monoclonal antibody, trastuzumab, significantly improved the prognosis for patients with HER2-positive breast cancer, however, increasing knowledge regarding mechanisms of resistance to trastuzumab have come to light, prompting research into additional methods to target the HER2 protein. The purpose of this article is to discuss evidence for why continued blockade of the HER2 pathway continues to be important despite progression on trastuzumab, as well as to review additional HER2-targeted therapies and progression in the central nervous system. With the availability of new drugs comes the need to determine the appropriate therapeutic combinations and optimal order in which to deliver these therapies. This review summarizes the practice-changing phase III trials and some supporting phase II data regarding the various targeted HER2 therapies available for patients with advanced HER2-positive breast cancer, proposes order for anti-HER2 therapy in the advanced HER2-positive breast cancer patient, and includes information on future strategies. While other reviews on HER2-targeted therapy are available, this review specifically aims at addressing treatment options after trastuzumab failure in the patient with advanced HER2-positive breast cancer.

Role of phosphatidylinositol 3,4,5-trisphosphate in cell signaling

Many lipids present in cellular membranes are phosphorylated as part of signaling cascades and participate in the recruitment, localization, and activation of downstream protein effectors. Phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3) is one of the most important second messengers and is capable of interacting with a variety of proteins through specific PtdIns(3,4,5)P3 binding domains. Localization and activation of these effector proteins controls a myriad of cellular functions including cell survival, proliferation, cytoskeletal rearrangement, and gene expression. Aberrations in the production and metabolism of PtdIns(3,4,5)P3 have been implicated in many human diseases including cancer, diabetes, inflammation, and heart disease. This chapter provides an overview of the role of PtdIns(3,4,5)P3 in cellular regulation and the implications of PtdIns(3,4,5)P3 dysregulation in human diseases. Additionally, recent attempts at targeting PtdIns(3,4,5)P3 signaling via small molecule inhibitors are summarized.

Emerging treatments for metastatic breast cancer: update from 2012

SUMMARY Metastatic breast cancer is still incurable and, thus, the goals of treatment focus on optimal palliation and extending the quality of survival through effective anticancer therapies that have acceptable toxicities. Cancer progression and development of drug resistance are dynamic processes of clonal adaptation both to evolving microenvironments with acquired tumor mutations and to continuous drug exposure. Preclinical research is constantly improving our understanding of breast cancer biology at a molecular level and, as such, current clinical research is focusing on designing trials with new targeted drugs and their appropriate combinations with endocrine and chemotherapy agents. In this review, we provide an overview of the most recent advances in the metastatic breast cancer setting by clinical subtype, giving emphasis to recently concluded or ongoing trials that have the potential to challenge and change current clinical practice.

HER2 Status by Standardized Immunohistochemistry and Silver-Enhanced In Situ Hybridization in Korean Breast Cancer

PURPOSE

Amplification of the human epidermal growth factor receptor 2 (HER2) gene occurs in 18% to 20% of breast cancers, and it is recognized as a prognostic and predictive marker. We investigated the HER2 status in Korean breast cancer by immunohistochemistry (IHC) and silver-enhanced in situ hybridization (SISH), as the first step toward building a nationwide quality assurance program for HER2 testing.

METHODS

A total of 1,198 breast carcinoma samples were collected from six institutions and IHC and SISH were performed using tissue microarrays in central laboratories. The results were compared to those of local laboratories.

RESULTS

Available data were obtained from 959 samples. Central IHC results were negative, equivocal, and positive for 756 (78.8%; range among institutions, 76.8-81.8%), 37 (3.9%; 1.9-6.2%), and 166 (17.3%; 13.6-20%), respectively. SISH results were negative, equivocal, and positive for 756 (78.8%; 77.4-79.9%), 2 (0.2%; 0-0.7%), and 201 (21%; 20.1-22.2%), respectively. HER2 gene amplification was observed in 4.4%, 19%, and 73.9% of the negative, equivocal and positive groups stratified by local IHC results, respectively. When central SISH was considered to be the gold standard method for measuring HER2 status, the false-negative and false-positive rates of local IHC were 14.4% (29/201) and 7.1% (54/756). The concordance rate between central IHC and SISH was 98.4%.

CONCLUSION

Central IHC and SISH markedly decreased the interlaboratory variability of HER2 status and the results of the two were highly concordant. The quality control program for HER2 testing must be focused on decreasing both the false negativity and positivity of IHC in local laboratories.

[Targeted based therapies in metastatic breast cancer: future evolution]

Research on molecular alteration process mechanisms leading to cancerogenesis permitted the elaboration of many targeted therapies. Some therapeutic classes appeared recently and are currently being tested, including HER-2 dimerization inhibitors. However, most of these therapies are mostly ineffective with monotherapy. Clinical trials are ongoing, testing their efficiency in association with other molecules of the therapeutic arsenal which is available in oncology. Nevertheless, breast cancer remains a pathology life-threatening, most of the time. Within this review will be introduced the most efficient of these targeted therapies, including their eventual association with other cytotoxic molecules.

Adjuvant lapatinib for women with early-stage HER2-positive breast cancer: a randomised, controlled, phase 3 trial

BACKGROUND

Worldwide, many patients with HER2-positive early stage breast cancer do not receive trastuzumab-the standard adjuvant treatment. We investigated the efficacy and safety of adjuvant lapatinib for patients with trastuzumab-naive HER2-positive early-stage breast cancer, started at any time after diagnosis.

METHODS

This study was a placebo-controlled, multicentre, randomised phase 3 trial. Women outpatients from 405 [corrected] centres in 33 countries [corrected] with HER2-positive early-breast cancer who had previously received adjuvant chemotherapy but not trastuzumab were randomly assigned (1:1) to receive daily lapatinib (1500 mg) or daily placebo for 12 months. Randomisation was done with a computer-generated sequence, stratified by time since diagnosis, lymph node involvement at diagnosis, and tumour hormone-receptor status. Investigators, site staff, and patients were masked to treatment assignment. The primary endpoint was disease-free survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00374322.

FINDINGS

Between August, 2006, and May, 2008, 3161 women were enrolled and 3147 were assigned to lapatinib (n=1571) or placebo (n=1576). After a median follow-up of 47·4 months (range 0·4-60·0) in the lapatinib group and 48·3 (0·7-61·3) in the placebo group, 210 (13%) disease-free survival events had occurred in the lapatinib group versus 264 (17%) in the placebo group (hazard ratio [HR] 0·83, 95% CI 0·70-1·00; p=0·053). Central review of HER2 status showed that only 2490 (79%) of the randomised women were HER2-positive. 157 (13%) of 1230 confirmed HER2-positive patients in the lapatinib group and in 208 (17%) of 1260 in the placebo group had a disease-free survival event (HR 0·82, 95% 0·67-1·00; p=0·04). Serious adverse events occurred in 99 (6%) of 1573 patients taking lapatinib and 77 (5%) of 1574 patients taking placebo, with higher incidences of grade 3-4 diarrhoea (97 [6%] vs nine [<1%]), rash (72 [5%] vs three [<1%]), and hepatobiliary disorders (36 [2%] vs one [<1%]).

INTERPRETATION

Our data show that there was no significant difference in disease-free survival between groups when analysed in the intention-to-treat population. However, exploratory analyses restricted to patients who had HER2-positive disease confirmed by central fluorescence in-situ hybridisation review suggested marginal benefit with lapatinib in terms of disease-free survival. Thus lapatinib might be an option for women with HER2-positive breast cancer who do not or cannot receive adjuvant trastuzumab.

FUNDING

GlaxoSmithKline.