HER2 status and efficacy of adjuvant anthracyclines in early breast cancer: a pooled analysis of randomized trials

Predicting anthracycline benefit: have we made any progress?

PURPOSE OF REVIEW

The benefit from anthracycline-based vs. nonanthracycline-based adjuvant therapy is not experienced by all breast cancer patients. Identification of the individuals to derive this benefit may be guided by predictive biomarkers. This review focuses on the search for biomarkers, particularly focusing on the potential roles for HER-2 and/or topoisomerase IIalpha.

RECENT FINDINGS

Clarification of differential sensitivity to anthracyclines is complicated due to disease heterogeneity, complexity of underlying biological pathways, biomarker detection methods and features of study design. Meta-analyses suggest anthracycline benefit is restricted to patients with HER-2 amplified disease. However, diversity within HER-2 positive and HER-2 negative subgroups limits the use of HER-2 status as an independent marker. Certainly, subgroups within HER-2 negative disease have demonstrable incremental benefit from anthracycline-based therapy. Regarding topoisomerase IIalpha, the best method of detection and predictive role remain unclear.

SUMMARY

Although progress has been made in defining breast cancer subgroups and identifying patients with general chemosensitivity, we do not yet have reliable predictive markers for anthracyclines. With current evidence, neither HER-2 status nor topoisomerase IIalpha status can be considered clinically valuable in guiding prescription of anthracyclines. Disease heterogeneity may dictate prediction by tumour profiles, rather than any single marker. These profiles may incorporate a panel of markers, including not only tumour features, such as HER-2 and topoisomerase IIalpha, but also host-determined features, such as stroma and stroma-anthracycline interaction. A new generation of well powered clinical trials that attempt to incorporate breast cancer heterogeneity may bridge the gap between available results and individual patient care.

[Gene expression based multigene prognostic and predictive tests in breast cancer]

Patient tailored therapy will serve the fundamentals of future cancer treatment. For this it will be imperative to characterize the tumor and to acquire precise predictive and prognostic information. We can achieve this by using not only monogenic (like ER, PR, HER-2, Ki-67) but also multigene assays, which can provide answers to several diagnostic questions simultaneously. We present a summary of currently available RT-PCR and microarray based multigene tests including MammaPrint, Oncotype DX, BLN Assay, Theros Breast Cancer Index SM, MapQuant DX, ARUP Breast Bioclassifier, Celera Metastatic Score, eXagen BCtm, Invasive Gene Signature, Wound Response Indicator and Mammostrat. Two of these (Oncotype DX and MammaPrint) are already incorporated in several diagnostic protocols. However, multiple unsolved issues deteriorate the value of these tests: generally the validation is poor, the gene sets do not confirm each other, the associated costs are high and the necessary bioinformatics is highly complex.

Topoisomerase IIalpha expression rather than gene amplification predicts responsiveness of adjuvant anthracycline-based chemotherapy in women with primary breast cancer

INTRODUCTION

Adjuvant anthracycline-based chemotherapy (AbCTX) is a standard treatment for patients with primary breast cancer. Its main target is topoisomerase IIalpha (TopIIa), a nuclear protein which is important for DNA replication and mitosis. We propose that the overexpression of the TopIIa protein or amplification of the TopIIa gene may be useful in predicting increased responsiveness towards AbCTX.

METHODS

Tumor tissues of 118 patients who received adjuvant AbCTX were examined by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH) for TopIIa and HER2. For IHC, the primary antibodies 485 (Dako) and NCL-TOPOIIA (Novocastra) were used. FISH analysis was performed with the SPEC HER2/CEP 17 Dual Color Probe (Zytovision) and LSI TOP 2A Spectrum Orange/CEP 17 Spectrum Green probe (Abbott). TopIIa IHC was evaluated by the immunoreactive score (IRS). FISH amplification was stated at an HER2-TopIIa/CEP 17 ratio > or = 2, deletion of TopIIa at a ratio <0.8.

RESULTS

The median age of the patient population was 50 years (range 23-77), 76 (64%) had tumors >2 cm in size, 98 (85%) were nodal positive, and 72 (66%) estrogen-receptor positive. Chemotherapy regimes consisted of epirubicin-cyclophosphamide (EC 40 pts), EC-CMF (18 pts), FAC/FEC (33 pts), anthracycline-taxane combinations (23 pts) and others (4 pts). After IHC, it was found that 19% of the tumors were positive for HER2 (3+) and the median IRS for TopIIa staining was 2 (49% positive); 28 (24%) tumors showed HER2 amplification, therefrom 20/22 (91%) within the HER2 3+ group. TopIIa gene was amplified in 17 cases (16%) and deletion was seen in 6 (5%) tumors. Of all cases with HER2 gene amplification, 14 (50%) cases of TopIIa co-amplification and one case of deletion were seen. Looking at histological parameters, TopIIa IHC correlated with nodal status (P = 0.018) and high grading (G3) (P = 0.047). After a median follow-up of 42 months (range 1-242), a significant prognostic factor for local recurrence was HER2 positivity (IHC P = 0.013 and FISH P = 0.023). Thirty-two patients developed metastasis (27%), which was correlated with HER2 FISH positivity (P = 0.024) and, as a trend, Top IIa IHC negativity (P = 0.094); 25 (21%) patients died from the disease. Negative prognostic parameters were the lack of estrogen-receptor expression (P = 0.008), lymphangiosis (P = 0.02), and TopIIa IHC negativity (P = 0.03).

CONCLUSION

In this cohort of patients, HER2 positivity indicated higher rates of local and distant recurrence. In contrast, TopIIa IHC positivity predicted lower risk of metastases and death, thus being a positive-predictive factor for the responsiveness to AbCTX. TopIIa gene amplification did not add predictive information. Therefore, we conclude that TopIIa protein expression might rather be the target of anthracyclines independent from gene copy number.

Clinical trial designs for evaluating the medical utility of prognostic and predictive biomarkers in oncology

Physicians need improved tools for selecting treatments for individual patients. Many diagnostic entities hat were traditionally viewed as individual diseases are heterogeneous in their molecular pathogenesis and treatment responsiveness. This results in the treatment of many patients with ineffective drugs, incursion of substantial medical costs for the treatment of patients who do not benefit and the conducting of large clinical trials to identify small, average treatment benefits for heterogeneous groups of patients. In oncology, new genomic technologies provide powerful tools for the selection of patients who require systemic treatment and are most (or least) likely to benefit from a molecularly targeted therapeutic. In the large amount of literature on biomarkers, there is considerable uncertainty and confusion regarding the specifics involved in the development and evaluation of prognostic and predictive biomarker diagnostics. There is a lack of appreciation that the development of drugs with companion diagnostics increases the complexity of clinical development. Adapting to the fundamental importance of tumor heterogeneity and achieving the benefits of personalized oncology for patients and healthcare costs will require paradigm changes for clinical and statistical investigators in academia, industry and regulatory agencies. In this review, I attempt to address some of these issues and provide guidance on the design of clinical trials for evaluating the clinical utility and robustness of prognostic and predictive biomarkers.

High levels of uPA and PAI-1 predict a good response to anthracyclines

Urokinase-type plasminogen activator (uPA) and its main inhibitor (PAI-1) were shown with level 1 evidence to be prognostic factors for primary breast cancer. Our preliminary retrospective study on a cohort of 1,220 consecutive patients hinted that uPA and PAI-1 could also serve as predictive factors for systemic therapy, namely that patients with high levels of the two markers benefit much more from anthracycline-based chemotherapy than patients with low levels of the two markers. The latter could equally well be treated with less toxic CMF-based chemotherapy (cyclophosphamide, methotrexate, and fluorouracil). The retrospective study, however, suffered from severely uneven patient and tumor characteristics as the patients were treated per institutional guidelines valid at the time and were not randomized between the anthracycline and CMF arms. In the present paper, we attempted to remedy this shortcoming and recheck our previous observations on more balanced data. To this end we employed a custom-made computer algorithm that selected 180 patients out of a total of 1,220 patients such that we obtained very well balanced anthracycline and CMF arms according to patient and tumor characteristics. Moreover, the low and high uPA/PAI-1 subgroups within both arms were also completely balanced. The algorithm in a way created a similar setting to that of a randomized study at the expense of greatly reducing the number of patients included into the study. In this setting, we observed the 3-year disease-free survival (DFS) in all four subgroups (according to treatment and levels of markers: both uPA and PAI-1 low versus one or both high). We report that the 3-year DFS in the CMF arm differed significantly: 87.1% for patients with low levels of markers versus 77.0% for patients with high levels of markers (P = 0.044, HR = 2.81, 95% CI = 0.98-8.04). On the other hand, the 3-year DFS in the anthracycline arm did not differ much between the two marker level subgroups: 85.2% for patients with low levels of markers versus 81.8% for patients with high levels of markers. Our observation points out that worse prognosis correlated to high uPA and PAI-1 levels can be reversed by treatment efficacy achieved through anthracycline-based chemotherapy. Based on this observation, we hypothesize that uPA/PAI-1 combination could be predictive for response to systemic therapy.

HER2, TOP2A, and TIMP-1 and responsiveness to adjuvant anthracycline-containing chemotherapy in high-risk breast cancer patients

PURPOSE To evaluate whether the combination of HER2 with TIMP-1 (HT) or TOP2A with TIMP-1 (2T) more accurately identifies patients who benefit from cyclophosphamide, epirubicin, and fluorouracil (CEF) compared with cyclophosphamide, methotrexate, and fluorouracil (CMF) than these markers do when analyzed individually. PATIENTS AND METHODS The Danish Breast Cancer Cooperative Group (DBCG) 89D trial randomly assigned 980 high-risk Danish breast cancer patients to CMF or CEF. Archival tumor tissue was analyzed TIMP-1, and HER2-negative and TIMP-1 immunoreactive tumors were classified as HT nonresponsive and otherwise HT responsive. Similarly, the 2T panel was constructed by combining TOP2A and TIMP-1; tumors with normal TOP2A status and TIMP-1 immunoreactivity were classified as 2T-nonresponsive and otherwise 2T-responsive. Results In total, 623 tumors were available for analysis, of which 154 lacked TIMP-1 immunoreactivity, 188 were HER2 positive, and 139 had a TOP2A aberration. HT status was a statistically significant predictor of benefit from CEF compared with CMF (P(interaction) = .036 for invasive disease-free survival [IDFS] and .047 for overall survival [OS]). The 269 (43%) patients with a 2T-responsive profile had a significant reduction in IDFS events (adjusted hazard ratio, 0.48; 95% CI, 0.34 to 0.69; P < .001) and OS events (adjusted hazard ratio, 0.54; 95% CI, 0.38 to 0.77; P < .001). 2T status was a highly significant predictor of benefit from CEF compared with CMF (P(interaction) < .0001 for IDFS and .004 for OS). CONCLUSION The 2T profile is a more accurate predictor of incremental benefit from anthracycline-containing chemotherapy than HER2, TIMP-1, or TOP2A individually, and compared with these, 2T classifies a larger proportion of patients as sensitive to anthracyclines.

Progression and treatment of HER2-positive breast cancer

PURPOSE

Approximately 20-30% of breast cancer tumors overexpress or amplify human epidermal growth factor receptor 2 (HER2). The role of this receptor in the progression of HER2+ breast cancer and resistance to certain anticancer monotherapies was investigated. The results of several pre-clinical and clinical trials, with the aim of determining the most safe and effective course of treatment for HER2+ breast cancer, were also thoroughly examined.

METHODS

A thorough search of databases including Pubmed, Springer, and The American Society of Clinical Oncology was performed, and pertinent studies were identified. The most relevant studies were preclinical, phase II, and III clinical trials identifying the function of the HER2 receptor in HER2+ breast cancer progression, as well as studies assessing the efficacy of monotherapy and combination therapy in the treatment of this aggressive form of cancer.

RESULTS

The HER2 receptor belongs to a family of receptors that consists of four cell-surface receptors (HER1-4) that share strong homology with the epidermal growth factor receptor (EGFR). All HER receptors interact with specific types of ligands to induce receptor activation, except for HER2, for which no known ligand has yet been identified. HER2 is activated by forming dimers with other HER receptors, and this results in a stronger and more prolonged signal transduction event. When expressed at normal levels, HER2 regulates cell growth, differentiation, and survival. However, under pathological conditions of HER2 overexpression, numerous HER2 heterodimers are formed resulting in aggressive tumor growth. Therefore, the prognosis associated with HER2-positive breast cancer is usually poor. A specific cohort of patients with breast cancer whose tumors test both hormone receptor (estrogen receptor [ER] and progesterone receptor [PR]) and HER2 positive have been found to be resistant to targeted hormone therapy. Studies investigating the etiology of this resistance have found that the cell membrane estrogen receptor communicates with HER2 in promoting the release of ER coactivators that cause the endocrine drug and selective estrogen receptor modulator, tamoxifen, to act as an agonist rather than an antagonist of the hormone estrogen. Thus, research has directed its inquiry toward the development of therapies specifically targeting HER2. The development of trastuzumab, a recombinant monoclonal antibody against HER2, initially proved to be a well-tolerated first line of treatment. However, in the long-term patients, trastuzumab was shown to develop resistance to this monotherapy. Therefore, research on HER2 positive breast cancer has focused on the study of different anti-HER2 combination therapies over the past decade.

CONCLUSIONS

While the development and approval of the HER2-targeted recombinant monoclonal antibody trastuzumab (Herceptin) has been efficacious in slowing HER2 cancer progression, combining this and other anti-HER2 therapy with either chemotherapy or endocrine therapy has proven more effective in improving overall and progression free survival.

Relationship between Topoisomerase 2A RNA Expression and Recurrence after Adjuvant Chemotherapy for Breast Cancer

PURPOSE: To perform an exploratory analysis of the relationship between gene expression and recurrence in operable hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-normal breast cancer patients treated with adjuvant doxorubicin-containing chemotherapy. EXPERIMENTAL DESIGN: RNA was extracted from archived tumor samples derived from 378 patients with stage I to III HR-positive, HER2-normal breast cancer and analyzed by reverse transcription-PCR for a panel of 374 genes, including the 21-gene recurrence score (RS). Patients were randomized to receive adjuvant doxorubicin plus cyclophosphamide or docetaxel in trial E2197, with no difference in recurrence seen in the treatment arms. All available recurrent cases were selected plus a nonrecurrent cohort. Cox proportional hazard models were used to identify relationships between gene expression and recurrence. RESULTS: TOP2A expression exhibited the strongest association with increased recurrence risk (P = 0.01), and was significantly associated with recurrence (P = 0.008) in a multivariate analysis adjusted for clinicopathologic features. Elevated TOP2A expression above the median was associated with a 2.6-fold increase (95% confidence interval, 1.3-5.2; P = 0.008) in risk of recurrence if the RS was <18, and a 2.0-fold increase (95% confidence interval, 1.2-3.2, P = 0.003) if there was an intermediate RS of 18 to 30. CONCLUSIONS: In patients with HR-positive, HER2-normal breast cancer, a population known to have a low incidence of TOP2A gene alterations thought to be predictive of anthracycline benefit, there is a range of TOP2A RNA expression that is strongly associated with recurrence after adjuvant anthracyclines, which provides information complementary to RS, indicating that it merits further evaluation as a prognostic and predictive marker. (Clin Cancer Res 2009;15(24):7693-700).

Triple-negative breast cancer--current status and future directions

Triple-negative breast cancer (TNBC) is defined by a lack of expression of both estrogen and progesterone receptor as well as human epidermal growth factor receptor 2. It is characterized by distinct molecular, histological and clinical features including a particularly unfavorable prognosis despite increased sensitivity to standard cytotoxic chemotherapy regimens. TNBC is highly though not completely concordant with various definitions of basal-like breast cancer (BLBC) defined by high-throughput gene expression analyses. The lack in complete concordance may in part be explained by both BLBC and TNBC comprising entities that in themselves are heterogeneous. Numerous efforts are currently being undertaken to improve prognosis for patients with TNBC. They comprise both optimization of choice and scheduling of common cytotoxic agents (i.e. addition of platinum salts or dose intensification strategies) and introduction of novel agents (i.e. poly-ADP-ribose-polymerase-1 inhibitors, agents targeting the epidermal growth factor receptor, multityrosine kinase inhibitors or antiangiogenic agents).

Predicting responses to chemotherapy in breast cancer: from bench to bedside

Recent progress in biotechnology, notably microarray analyses, makes it possible to examine the genome-based characteristics of tumors with different prognoses and predict responses to chemotherapy. Furthermore, pharmacogenomic techniques are expected to predict the optimal regimen for individual patients that will provide high benefits with reduced toxicity. Some predictive or prognostic tests for breast cancer are now moving from bench to bedside.

DNA methylation as a biomarker in breast cancer

In cancer, epigenetic changes such as covalent addition of methyl groups to the genomic DNA itself are more prominent than genetic changes. Cytosine–phosphate–guanosine (CpG) methylation negatively affects gene transcription of an adjacent gene. It is thought that DNA methylation significantly contributes to all hallmarks of cancer. Next to being a potential therapy target, DNA methylation is an emerging field of biomarkers. Technically, DNA provides a stable and robust analyte that is particularly suitable for clinical applications. Moreover, there are numerous potential human DNA sources that could facilitate integration of methylation tests in clinical practice. In breast cancer, DNA methylation has shown promise as a potential biomarker for early detection, therapy monitoring, assessment of prognosis or prediction of therapy response. In particular, paired-like homeodomain transcription factor 2 (PITX2) DNA methylation has been validated using a robust assay for paraffin-embedded tissue for clinically relevant outcome prediction in early breast cancer patients treated by adjuvant tamoxifen therapy.

Role of Anthracyclines in the Treatment of Early Breast Cancer

Purpose

To review data relating to anthracyclines in the adjuvant treatment of early breast cancer.

Design

This is a report from a seminar in which the future of anthracyclines in the adjuvant treatment of breast cancer was considered. In particular, the question of whether anthracyclines should now be discarded and replaced by taxanes was addressed.

Results

Accumulating data from large randomized trials indicate that genetic markers may have a role in predicting sensitivity to cytotoxic drugs. However, no reliable, validated test is available for predicting sensitivity to anthracyclines in particular. Topoisomerase IIα amplification and/or deletion, especially in conjunction with human epidermal growth factor receptor-2 amplification, has been proposed to fulfill this role but more data are needed. Currently, only one published trial has shown that a taxane-based regimen may be superior to an anthracycline-based regimen, but several trials indicate that combinations including both anthracyclines and taxanes may be better still. Further studies aimed at optimizing anthracyclines and taxanes in combination, and integrating biologic agents, seem to be the way forward. There is no validated test that can determine whether anthracyclines can be of greater benefit than other agents for individual patients.

Conclusion

Anthracyclines have been extensively tested in clinical trials spanning several decades; currently, there are insufficient data to recommend replacing them in the adjuvant treatment of breast cancer.

The role of topoisomerase IIalpha and HER-2 in predicting sensitivity to anthracyclines in breast cancer patients

Human epidermal growth factor receptor-2 (HER-2) and topoisomerase IIalpha (topo IIalpha) co-inhabit chromosome 17. In the search for predictive biomarkers to refine clinical prescription of cytotoxic agents, both HER-2 and topo IIalpha are under exploration for their potential role in identifying individuals with early breast cancer who may benefit from anthracycline therapy. Whilst recent meta-analyses support a predictive role for HER-2 amplification, it remains unclear whether HER-2 is the critical biomarker or whether it is a surrogate marker for topo IIalpha alteration, a known drug target of anthracyclines. The major limitation in considering HER-2 as a single marker is heterogeneity within the subgroups of HER-2 positive and HER-2 negative disease. For topo IIalpha, current data is inconclusive. Issues plaguing this field are technical variability in marker definition, complex regulation pathway of topo IIalpha and lack of prospective, adequately powered studies. With current evidence, neither HER-2 nor topo IIalpha gene status can be considered clinically valuable markers for anthracycline benefit. This paper will focus on issues relating to reliable detection and predictive analyses of HER-2 and topo IIalpha, and highlight potential developments in improving individualized approach to anthracycline use in early breast cancer patients.

Genetic characterization of breast cancer and implications for clinical management

Breast cancer is a genetic disease caused by the accumulation of mutations in neoplastic cells. In the last few years, high-throughput microarray-based molecular analysis has provided increasingly more coherent information about the genetic aberrations in breast cancer. New biomarkers and molecular techniques are slowly becoming part of the diagnostic and prognostic armamentarium available for pathologists and oncologists to tailor the therapy for breast cancer patients. In this review, we will focus on the contribution of breast cancer somatic genetics to our understanding of breast cancer biology and its impact on breast cancer patient management.

Evaluation of HER2 in breast cancer: reality and expectations

BACKGROUND

The introduction of drugs, whose mechanisms of action are directed against specific molecules involved in cancer initiation and/or progression, has changed the daily workup of breast cancer patients. At present, HER2 expression and/or amplification should be evaluated in every primary invasive breast cancer either at the time of diagnosis or at the time of recurrence, mostly to guide selection of trastuzumab in the adjuvant and/or metastatic setting. The adequate selection of patients is an essential step for indication of anti-HER2 therapy.

OBJECTIVE

This review focuses on the state of the art for HER2 evaluation in breast cancer, as well as expectations regarding future molecular assays based on mechanisms of resistance to HER2-driven therapy.

METHODS

Data were obtained by searching the PubMed database, including the terms 'HER2', 'in situ hybridisation', 'immunohistochemistry', 'trastuzumab', 'breast cancer', 'therapy', 'resistance' and 'tyrosine-kinase inhibitors', with a preference for updated publications.

CONCLUSION

Pathologists have a central role in the selection of patients who will benefit from anti-HER-based therapies, with a responsibility to obtain the most reliable results for immunohistochemistry and in situ hybridisation techniques. Pre-analytical variables, such as type of fixative and time of fixation, are critical to guarantee consistent and quality assays, as well as to facilitate interpretation and decrease interobserver variability. Rigorous quality control and centralisation of techniques/interpretation of results are recommended to guarantee consistent assays.

Uracil-tegafur and tamoxifen vs cyclophosphamide, methotrexate, fluorouracil, and tamoxifen in post-operative adjuvant therapy for stage I, II, or IIIA lymph node-positive breast cancer: a comparative study

BACKGROUND

It has been reported that treatment with uracil-tegafur (UFT) has shown significantly better survival and relapse-free survival (RFS) than surgery alone. Therefore, we compared UFT with a combination therapy of cyclophosphamide, methotrexate, and fluorouracil (CMF) in patients who had undergone curative surgery for axillary lymph node-positive breast cancer.

METHODS

A total of 377 node-positive patients with stage I, II, or IIIA disease were registered from September 1996 through July 2000 and were randomly assigned to either 6 cycles of CMF or 2 years of UFT. In both arms, tamoxifen (TAM) was concurrently administered for 2 years. The primary end point in this study was the non-inferiority of UFT to CMF.

RESULTS

No statistically significant difference between the two groups was observed with regard to the 5-year RFS rate (72.2% in the UFT and 76.3% in the CMF). Adverse event profiles differed between the two groups, with a significantly lower incidence of leukopenia and anaemia in the UFT group, as well as anorexia, nausea/vomiting, stomatitis, and alopecia, which have implications for quality of life.

CONCLUSION

UFT administered in combination with TAM holds promise in the treatment of lymph node-positive early breast cancer. On stratified analysis, the recurrence rate in the UFT group was found to be better in oestrogen receptor (ER)-positive patients. Tegafur-based treatment should be evaluated by a prospective randomised trial conducted in ER-positive patients.

Prognostic value of serum vascular endothelial growth factor in Egyptian females with metastatic triple negative breast cancer

OBJECTIVES

The aim of this work was to explore the value of serum vascular endothelial growth factor-A (VEGF-A) in patients with metastatic triple negative breast cancer (TNBC) treated with chemotherapy. The primary end point was overall survival (OS). Secondary end points were response rate (RR), progression-free survival (PFS) and VEGF-A level at baseline, mid-therapy and at the end of therapy.

DESIGN AND METHODS

Female patients aged 18 years or above with histologically proven metastatic TNBC were included. Serum VEFG-A levels were measured at baseline, after the 3rd and 6th cycles of FAC chemotherapy regimen (Fluorourcil, Adriamycin, and Cyclophamide).

RESULTS

The overall RR was 57%. The median PFS and OS were 7 and 11.2 months, respectively (95% CI: 4.3-9.7 and 3.8-18.5 months, respectively). Patients whose disease progressed despite therapy had a significantly higher baseline VEGF-A level than those who did not progress. VEGF-A level did not drop with continuation of therapy. Patients with high VEGF-A level had a significantly lower PFS but not OS than patients with low levels.

CONCLUSION

The outcome of metastatic TNBC is poor with FAC chemotherapy regimen. Alternative chemotherapeutic regimens and novel therapeutic approaches including targeting of VEGF and/or its receptors are warranted.

Lack of TIMP-1 tumour cell immunoreactivity predicts effect of adjuvant anthracycline-based chemotherapy in patients (n=647) with primary breast cancer. A Danish Breast Cancer Cooperative Group Study

PURPOSE

A number of prospective studies have shown that adjuvant CEF significantly improves disease-free and overall survival as compared to CMF in breast cancer patients. Our aim was to determine whether the benefit of epirubicin versus methotrexate differs according to TIMP-1 tumour cell immunoreactivity.

EXPERIMENTAL DESIGN

Tissue micro arrays from 647 patients randomly assigned to CMF or CEF in DBCG trial 89D were included. The primary end-point was invasive disease-free survival (IDFS). A central assessment of tissue inhibitor of metalloproteinases 1 (TIMP-1) status was performed using immunohistochemistry (IHC). Tumours were regarded as TIMP-1 positive if epithelial breast cancer cells were stained using the anti-TIMP-1 monoclonal antibody VT7.

RESULTS

By central assessment 75% of tumours were classified as tumour cell TIMP-1 positive. Among CEF-treated patients, individuals with TIMP-1 negative tumours had a significant longer IDFS than patients with TIMP-1 positive tumours (p=0.047). The multivariate Cox regression analysis of IDFS showed that CEF was superior to CMF among patients with TIMP-1 negative tumours (hazard ratio (HR)=0.51; 95% confidence interval (CI): 0.31-0.84, p=0.0085), while no significant difference could be demonstrated among patients with TIMP-1 positive tumours (HR=0.88; 95% CI: 0.68-1.13, p=0.32). A non-significant TIMP-1 status (positive or negative) versus treatment (CMF or CEF) interaction was detected for IDFS (p=0.06) and OS (p=0.21).

CONCLUSION

Lack of TIMP-1 tumour cell immunoreactivity seems to predict a favourable effect of epirubicin-containing adjuvant therapy in primary breast cancer. However, an independent study is awaited to validate the potential predictive value of TIMP-1 immunoreactivity.

Paclitaxel as a first-line chemotherapy for Japanese women with advanced or recurrent breast cancer: a multi-institutional practice-based study by the Kyushu Breast Cancer Study Group (KBC-SG)

BACKGROUND

Anthracycline-containing chemotherapy has represented the standard treatment for advanced breast cancer. However, it is sometimes difficult to continue it because of its cumulative cardiac toxicity, and the benefit of adding anthracyclines to the chemotherapy regimen is confined to HER2-overexpressed breast cancer. A non-anthracycline-based novel therapy is necessary to improve the survival and reduce the toxicity.

METHODS

We evaluated the tumor response and adverse events of a first-line paclitaxel therapy in advanced or recurrent breast cancer in a variety of practice settings. Patients were to receive paclitaxel tri-weekly (175 mg/m(2)), bi-weekly (120 mg/m(2)) or weekly (80 mg/m(2)) until disease progression or toxicity precluded further treatment. Tumor response and toxicities were evaluated.

RESULTS

Thirty-three patients received a total of 191 cycles (median 5, range 2-19). All patients completed at least two cycles. In 30 patients who were evaluable for response, there were 16 overall responses [53%, 95% confidence interval (CI) 34-72%], including 5 complete responses (17%, 95% CI 3-31%). The median progression-free survival and overall survival were 16 (95% CI 9-24) months and 29 (95% CI 24-36) months, respectively. Overall treatment was well tolerated, and no myelosuppression >grade 3 was reported during this study. A grade 3 dyspnea was noted in one patient, but it recovered spontaneously, and subsequent administration of paclitaxel was successfully given with no specific treatment. No other toxicity greater than grade 3 was demonstrated.

CONCLUSION

Paclitaxel as a first-line therapy at this dose and schedule is an effective and well-tolerated treatment regimen in Japanese patients with advanced or recurrent breast cancer.

Topoisomerase II alpha and responsiveness of breast cancer to adjuvant chemotherapy

BACKGROUND

Amplification or deletion of the topoisomerase II alpha (TOP2A) gene in breast cancers has been postulated to be more closely associated with responsiveness to anthracycline-containing chemotherapy than amplification of the human epidermal growth factor receptor type 2 (HER2) gene.

METHODS

We studied 438 tumors from 710 premenopausal women with node-positive breast cancer who received cyclophosphamide, epirubicin, and 5-fluorouracil (CEF) or cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) as adjuvant chemotherapy in the randomized National Cancer Institute of Canada Clinical Trials Group Mammary 5 (MA.5) trial. TOP2A alterations and HER2 amplification were quantified by fluorescence in situ hybridization. The association of TOP2A and HER2 status with recurrence-free survival (RFS) and overall survival (OS) in the two treatment groups was analyzed using Kaplan-Meier curves, the log-rank test, and Cox proportional hazard models. All statistical tests were two-sided.

RESULTS

In patients whose tumors showed TOP2A alterations (either amplifications or deletions), treatment with CEF was statistically significantly superior to treatment with CMF in terms of RFS (adjusted hazard ratio [HR] = 0.35, 95% confidence interval [CI] = 0.17 to 0.73, P = .005) and OS (adjusted HR = 0.33, 95% CI = 0.15 to 0.75, P = .008). In patients without TOP2A amplification or deletion, the corresponding adjusted hazard ratios for RFS and OS were 0.90 (95% CI = 0.66 to 1.23, P = .49) and 1.09 (95% CI = 0.77 to 1.56, P = .62). Adjusted tests of interaction between treatment and TOP2A status were P = .09 for RFS and P = .02 for OS. Adjusted tests of interaction between treatment and HER2 status were P = .008 for RFS and P = .02 for OS.

CONCLUSION

TOP2A gene alterations (amplifications or deletions) are associated with an increase in responsiveness to anthracycline-containing chemotherapy regimens relative to non-anthracycline regimens that is similar to that seen in patients with HER2 amplification.

Recent advances in systemic therapy: new diagnostics and biological predictors of outcome in early breast cancer

The key to optimising our approach in early breast cancer is to individualise care. Each patient has a tumour with innate features that dictate their chance of relapse and their responsiveness to treatment. Often patients with similar clinical and pathological tumours will have markedly different outcomes and responses to adjuvant intervention. These differences are encoded in the tumour genetic profile. Effective biomarkers may replace or complement traditional clinical and histopathological markers in assessing tumour behaviour and risk. Development of high-throughput genomic technologies is enabling the study of gene expression profiles of tumours. Genomic fingerprints may refine prediction of the course of disease and response to adjuvant interventions. This review will focus on the role of multiparameter gene expression analyses in early breast cancer, with regards to prognosis and prediction. The prognostic role of genomic signatures, particularly the Mammaprint and Rotterdam signatures, is evolving. With regard to prediction of outcome, the Oncotype Dx multigene assay is in clinical use in tamoxifen treated patients. Extensive research continues on predictive gene identification for specific chemotherapeutic agents, particularly the anthracyclines, taxanes and alkylating agents.

Recent advances in systemic therapy: advances in adjuvant systemic chemotherapy of early breast cancer

Adjuvant treatment for early breast cancer is an evolving field. Since the advent of the initial cyclophosphamide, methotrexate and 5-fluorouracil (CMF) regimens, which reduced risk for recurrence and death, anthracyclines and subsequently taxanes were added to the cytotoxic armamentarium for use sequentially or in combination in the adjuvant setting. The efficacy and toxicity of each chemotherapy regimen must be viewed within the context of host co-morbidities and the specific biologic phenotype of the tumor. In the era of mammographic screening, small, node-negative breast cancer is the most frequent presentation of the disease. Patient selection for adjuvant chemotherapy has become a key issue. Traditional prognostic factors continue to be of value in determining the risk for relapse, but new and sophisticated genomic tools (such as Oncotype Dx^® and Mammaprint^®) are now available and may improve our ability to select patients. For those patients who do require adjuvant chemotherapy, the 'one size fits all' paradigm should never again feature in the treatment of early breast cancer, following the important insights yielded by biomarker research to identify those who will benefit the most from a particular drug. In this review we focus on some of the current controversies and potential future steps in adjuvant chemotherapy for treatment of early breast cancer.

Role of Trastuzumab in the Adjuvant Treatment of HER2-Positive Early Breast Cancer

Amplification of the human epidermal growth factor receptor 2 ( HER2) gene occurs in 18–23% of invasive breast carcinomas and is associated with a worse prognosis. This novel transforming gene was identified in 1985, and in 1987 HER2 amplification was demonstrated to be central to the aggressive, malignant phenotype of these cancers and a significant predictor of both time to relapse and overall survival. These observations led to the development of the first monoclonal antibody targeting the extracellular domain of HER2, trastuzumab (Herceptin®, Genentech and Hoffman LaRoche, Switzerland), which was approved by the US FDA for metastatic breast cancer in 1998. In 2005, results from four major trastuzumab adjuvant trials demonstrated a marked reduction in risk of recurrence, and trastuzumab is now an essential component of the adjuvant treatment of H ER2-positive early breast cancer. Concerns regarding cardiac safety and mechanisms of resistance to trastuzumab remain important issues and are being addressed in ongoing research efforts.

High quality copy number and genotype data from FFPE samples using Molecular Inversion Probe (MIP) microarrays

BACKGROUND

A major challenge facing DNA copy number (CN) studies of tumors is that most banked samples with extensive clinical follow-up information are Formalin-Fixed Paraffin Embedded (FFPE). DNA from FFPE samples generally underperforms or suffers high failure rates compared to fresh frozen samples because of DNA degradation and cross-linking during FFPE fixation and processing. As FFPE protocols may vary widely between labs and samples may be stored for decades at room temperature, an ideal FFPE CN technology should work on diverse sample sets. Molecular Inversion Probe (MIP) technology has been applied successfully to obtain high quality CN and genotype data from cell line and frozen tumor DNA. Since the MIP probes require only a small (approximately 40 bp) target binding site, we reasoned they may be well suited to assess degraded FFPE DNA. We assessed CN with a MIP panel of 50,000 markers in 93 FFPE tumor samples from 7 diverse collections. For 38 FFPE samples from three collections we were also able to asses CN in matched fresh frozen tumor tissue.

RESULTS

Using an input of 37 ng genomic DNA, we generated high quality CN data with MIP technology in 88% of FFPE samples from seven diverse collections. When matched fresh frozen tissue was available, the performance of FFPE DNA was comparable to that of DNA obtained from matched frozen tumor (genotype concordance averaged 99.9%), with only a modest loss in performance in FFPE.

CONCLUSION

MIP technology can be used to generate high quality CN and genotype data in FFPE as well as fresh frozen samples.

Docetaxel With Cyclophosphamide Is Associated With an Overall Survival Benefit Compared With Doxorubicin and Cyclophosphamide: 7-Year Follow-Up of US Oncology Research Trial 9735

PURPOSE

We previously reported that four cycles of docetaxel/cyclophosphamide (TC) produced superior disease-free survival (DFS) compared with four cycles of doxorubicin/cyclophosphamide (AC) in early breast cancer. Older women are under-represented in adjuvant chemotherapy trials. In our trial 16% of patients were > or = 65 years. We now report 7-year results for DFS and overall survival (OS) as well as the impact of age, hormone receptor status, and HER2 status on outcome and toxicity.

PATIENTS AND METHODS

Patients were randomly assigned to receive either four cycles of standard-dose AC (60/600 mg/m(2); n = 510), or TC (75/600 mg/m(2); n = 506), administered by intravenous infusion every 3 weeks.

RESULTS

The median age in women younger than 65, was 50 years (range, 27 to 64) and for women > or = 65 was 69 years (range, 65 to 77). Baseline characteristics in the two age subgroups were generally well matched, except that older women tended to have more lymph node involvement. At a median of 7 years follow-up, the difference in DFS between TC and AC was significant (81% TC v 75% AC; P = .033; hazard ratio [HR], 0.74; 95% CI 0.56 to 0.98) as was OS (87% TC v 82% AC; P = .032; HR, 0.69; 95% CI, 0.50 to 0.97). TC was superior in older patients as well as younger patients. There was no interaction of hormone-receptor status or HER-2 status and treatment. Older women experienced more febrile neutropenia with TC and more anemia with AC.

CONCLUSION

With longer follow-up, four cycles of TC was superior to standard AC (DFS and OS) and was a tolerable regimen in both older and younger patients.

Emerging biomarkers and new understanding of traditional markers in personalized therapy for breast cancer

The era of personalized medicine is likely to see an escalation in the use of biomarkers to ensure breast cancer patients receive optimal treatment. A combination of prognostic and predictive biomarkers should enable better quantification of the residual risk faced by patients and indicate the potential value of additional treatment. Established biomarkers such as estrogen receptor and progesterone receptor already play a significant role in the selection of patients for endocrine therapy. Human epidermal growth factor receptor 2 (HER2) is recognized as a strong predictor of response to trastuzumab whereas, more recently, the role of estrogen receptor and HER2 as negative and positive indicators for chemotherapy has also been explored. Ki67 has traditionally been recognized as a modest prognostic factor, but recent neoadjuvant studies suggest that on-treatment measurement may be a more effective predictor of treatment efficacy for both endocrine treatment and chemotherapy. The last decade has seen the emergence of numerous multigene expression profiles that aim to outdo traditional predictive and prognostic factors. The Oncotype DX assay and the MammaPrint profile are currently undergoing prospective clinical trials to clearly define their role. Other gene expression-based assays also show potential but are yet to be tested clinically. Rigorous comparison of these emerging markers with current treatment selection criteria will be required to determine whether they offer significant benefit to justify their use.

Long-term benefit of high-dose epirubicin in adjuvant chemotherapy for node-positive breast cancer: 15-year efficacy results of the Belgian multicentre study

PURPOSE

The 4-year results of this trial demonstrated that a higher dose of epirubicin with cyclophosphamide (HEC) is superior to a lower dose of epirubicin, 60 mg/m(2) (EC), for event-free survival (EFS; 27% reduction), but is not superior to classical oral cyclophosphamide, methotrexate, and fluorouracil (CMF) in the adjuvant treatment of node-positive breast cancer. Herein we report the 15-year data on efficacy and long-term toxicity of this three-arm Belgian multicenter trial.

PATIENTS AND METHODS

Between March 1988 and December 1996, 777 eligible patients were randomly assigned to six cycles of CMF, eight cycles of EC, or eight cycles HEC.

RESULTS

The 15-year EFS was 45% for patients who received CMF, 39% for patients who received EC, and 50% for patients who received HEC. The hazard ratios (HR) were 0.77 for HEC versus EC (95% CI, 0.60 to 0.98; P = .03), 0.90 for HEC versus CMF (P = .39), and 0.86 for EC versus CMF (P = .21). No difference in overall survival (OS) was seen. Cardiac toxicity was more frequent with HEC than with CMF (11 patients v 1 patient; P = .006), but no more than with EC (P = .21).

CONCLUSION

Treatment with HEC demonstrated superior EFS when compared with lower-dose epirubicin. However, we do not recommend the use of HEC regimen in daily clinical practice, mainly because of the higher risk of cardiotoxicity related to the cumulative doses of epirubicin and the lack of superiority of anthracyclines over CMF in our study.

National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for Use of Tumor Markers in Testicular, Prostate, Colorectal, Breast, and Ovarian Cancers

Background: Updated National Academy of Clinical Biochemistry (NACB) Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed.

Methods: Published reports relevant to use of tumor markers for 5 cancer sites—testicular, prostate, colorectal, breast, and ovarian—were critically reviewed.

Results: For testicular cancer, α-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase are recommended for diagnosis/case finding, staging, prognosis determination, recurrence detection, and therapy monitoring. α-Fetoprotein is also recommended for differential diagnosis of nonseminomatous and seminomatous germ cell tumors. Prostate-specific antigen (PSA) is not recommended for prostate cancer screening, but may be used for detecting disease recurrence and monitoring therapy. Free PSA measurement data are useful for distinguishing malignant from benign prostatic disease when total PSA is &lt;10 μg/L. In colorectal cancer, carcinoembryonic antigen is recommended (with some caveats) for prognosis determination, postoperative surveillance, and therapy monitoring in advanced disease. Fecal occult blood testing may be used for screening asymptomatic adults 50 years or older. For breast cancer, estrogen and progesterone receptors are mandatory for predicting response to hormone therapy, human epidermal growth factor receptor-2 measurement is mandatory for predicting response to trastuzumab, and urokinase plasminogen activator/plasminogen activator inhibitor 1 may be used for determining prognosis in lymph node–negative patients. CA15-3/BR27–29 or carcinoembryonic antigen may be used for therapy monitoring in advanced disease. CA125 is recommended (with transvaginal ultrasound) for early detection of ovarian cancer in women at high risk for this disease. CA125 is also recommended for differential diagnosis of suspicious pelvic masses in postmenopausal women, as well as for detection of recurrence, monitoring of therapy, and determination of prognosis in women with ovarian cancer.

Conclusions: Implementation of these recommendations should encourage optimal use of tumor markers.

The use of genomics in clinical trial design

Many cancer treatments benefit only a minority of patients who receive them. This results in an enormous burden on patients and on the health care system. The problem will become even greater with the increasing use of molecularly targeted agents whose benefits are likely to be more selective unless the drug development process is modified to include co-development of companion diagnostics. Whole genome biotechnology and decreasing costs of genome sequencing make it increasingly possible to achieve an era of predictive medicine in oncology therapeutics. The challenges are numerous and substantial but are not primarily technological. They involve organizing publicly funded diagnostics of deregulated pathways, adopting new paradigms for drug development, and developing incentives for industry to incur the complexity and expense of co-development of drugs and companion diagnostics. This article reviews some designs for phase III clinical trials that may facilitate movement to a more predictive oncology.