Trastuzumab and vinorelbine as first-line therapy for HER2-overexpressing metastatic breast cancer: multicenter phase II trial with clinical outcomes, analysis of serum tumor markers as predictive factors, and cardiac surveillance algorithm

The management of cancer in the elderly: targeted therapies in oncology

Cancer is universally considered a disease of ageing. Today the management of elderly cancer patients poses many specific problems and it should be revisited in the light of the most recent advances in both diagnosis and treatment of human malignancies. In particular, the potential use of novel therapeutic options, based on therapeutic agents raised against molecular targets (the so called targeted therapy), appears to be promising in this clinical settings especially in view of the limited side-effects. The mainstays of cancer treatment during the twentieth century were surgery, radiation and chemotherapy. However, surgery is not curative in metastatic disease, radiation and chemotherapy are limited by side effects because they can't discriminate between healthy and cancerous cells. When key molecular changes responsible for malignant transformation were identified (e.g. growth factors and their receptors), it was hoped that new targeted agents, by inhibiting cancer-specific pathways, would spare normal cells and thereby offer improved safety benefits and a higher therapeutic index over standard chemotherapeutics. The most common targeted therapies used in clinical practice, i.e. monoclonal antibodies and small molecules, are described.

Her2-positive breast cancer: herceptin and beyond

Breast cancer accounts for approximately 30% of all new cancer cases each year, with an annual incidence of approximately 200,000. Additionally, almost 25% of breast cancers are noted to overexpress Her2, which is an epidermal growth factor receptor. Overexpression of Her2 has been associated with a more aggressive phenotype with decreased survival. Trastuzumab, a recombinant monoclonal antibody against the Her2 receptor, is the only FDA-approved targeted agent for treatment of Her2-overexpressing breast cancer. However, despite the great success achieved with trastuzumab, many women will either not respond or eventually progress despite trastuzumab treatment. As a result, significant efforts have been applied to finding other therapies besides trastuzumab for the treatment of Her2-positive breast cancer. Work has been directed at trying to elucidate the exact mechanism of resistance to trastuzumab and identifying ways to overcome them, at increasing the efficacy of trastuzumab by combining it with other therapeutic agents and at investigating other novel agents.

HER2-targeted therapy in breast cancer. Monoclonal antibodies and tyrosine kinase inhibitors

There is strong clinical evidence that trastuzumab, a monoclonal antibody targeting the human epidermal growth factor receptor (HER) two tyrosine kinase receptor, is an important component of first-line treatment of patients with HER2-positive metastatic breast cancer. In particular the combination with taxanes and vinorelbine has been established. In the preoperative setting inclusion of trastuzumab has significantly increased the pathological complete response rate. Results from large phase III trials evaluating adjuvant therapy in HER2-positive early breast cancer indicate that the addition of trastuzumab to chemotherapy improves disease-free and overall survival. The use of lapatinib, a dual tyrosine kinase inhibitor of both HER1 and HER2, in combination with capecitabine in the second-line treatment of HER2-positive patients with metastatic breast cancer previously treated with trastuzumab has been established. There is modest, but still insufficient, support that the compound passes the blood-brain barrier. Several trials are ongoing both in the adjuvant and metastatic settings and we have to await the results of these to clarify the role of trastuzumab and lapatinib. The clinical problem of tumours developing resistance to HER2-directed therapy is becoming increasingly important. Several issues about optimal selection of patients, prevention of resistance and use of different treatment options are still unresolved. In this article, we summarise the current knowledge on clinical evidence of HER2-directed therapy and the potential mechanisms of underlying resistance, including the possible clinical implications and review new therapeutic options.

Phase II trial of vinorelbine and trastuzumab in patients with HER2-positive metastatic breast cancer. A prospective, open label, non-controlled, multicenter phase II trial (to investigate efficacy and safety of this combination chemotherapy)

The purpose of this study was to evaluate the efficacy (progression free survival (PFS) and response rate) and safety of vinorelbine and trastuzumab combination chemotherapy in patients with HER2-overexpressing, metastatic breast cancer as a first line chemotherapy regimen. Patients with histologically confirmed, HER2-positive (immunohistochemistry (ICH) 3+, or 2+ and FISH+) metastatic breast cancer who had nor received prior vinorelbine or anti-HER2 therapy in the adjuvant setting, received at least eight weeks of vinorelbine i.v. (25 mg/g weekly) and trastuzumab (4 mg/kg on day 1 followed by 2 mg/kg weekly). Forty-one women from six participating centers were enrolled into the trial. The overall response rate, was 43.9% (18 of 41 patients), (CI 28-60.3%), 30% of patients were progression free after 1 year. Four patients reached complete remission, 14 partial remission and five had stable disease for at least 18 weeks. Six patients developed primary progression. 35 patients (85%) experienced progression after a median time of 235 days. Therapy was in general well-tolerated. There were two CTC grade 4 infusion syndromes and two patients experienced cardiotoxicity at least grade 2. This phase II trial of vinorelbine and trastuzumab demonstrated an effective and well-tolerated regimen with a favourable safety profile.

Metastatic breast cancer: the treatment challenge

As therapeutic options have multiplied, chemotherapy for metastatic breast cancer (MBC) has become increasingly complex. Furthermore, advances in the treatment of early-stage breast cancer, in particular the development of taxane-based regimens, have led to increased use of adjuvant chemotherapy. As a result, the decisions regarding the treatment of patients presenting with MBC have become more difficult, because many patients are likely to have received a variety of adjuvant chemotherapy regimens. The primary goal of treatment for MBC is palliation of disease--usually with prolongation of survival--with minimal toxicity. However, there is currently no "gold standard" in this setting, and the literature supports many choices for first- and second-line treatment. Other issues as yet unsettled in these patients are (1) whether to combine >or= 2 drugs or to use each drug alone until disease progression; (2) how to use novel targeted biologic agents; and (3) how to treat patients with HER2-overexpressing tumors after adjuvant treatment with trastuzumab. The role of taxanes, antimetabolites, and targeted agents in patients with MBC will be discussed in this review, particularly in the context of previous adjuvant therapy. The controversy surrounding the use of doublet or sequential therapy will also be discussed. Although considerable advances have been made toward answering these questions, many additional uncertainties have arisen, and further well-designed randomized studies are needed.

A phase II study of weekly vinorelbine and trastuzumab in patients with HER2-positive metastatic breast cancer

BACKGROUND

Trastuzumab combined with cytotoxic agents presents encouraging results in metastatic breast cancer (MBC), but cardiac toxicity limits some combinations. The synergism shown with trastuzumab and the favorable tolerability profile of vinorelbine provided the rationale for investigating this combination.

PATIENTS AND METHODS

Patients with HER2-positive MBC who had received <2 lines of chemotherapy for metastatic disease were included. Vinorelbine (25 mg/m2 on day 2, then weekly on day 1) and trastuzumab (4 mg/kg on day 1, then 2 mg/kg weekly) were administered for a maximum of 6 cycles (1 cycle=3 weeks).

RESULTS

A total of 52 patients were enrolled. The median age was 50 years (range, 26-79 years). Ninety percent of the patients had received adjuvant chemotherapy, 42% received a first line of chemotherapy for MBC, and 69% had disease at visceral sites. The overall response rate was 58% (95% CI, 43%-71%). The median time to progression and overall survival were 7 months (95% CI, 5-9 months) and 26 months (95% CI, 20-32 months), respectively. Grade 4 neutropenia was present in 3 courses; neutropenic fever was not reported. The main grade 3 nonhematologic toxicities were asthenia, neuropathy, diarrhea, alopecia, and nausea/vomiting. No patients experienced serious cardiac toxicity.

CONCLUSION

These results confirm that weekly vinorelbine/trastuzumab is an active and safe regimen in patients with HER2-positive MBC with an unfavorable prognosis.

ErbB-2 inhibition activates Notch-1 and sensitizes breast cancer cells to a gamma-secretase inhibitor

ErbB-2 overexpression in breast tumors is associated with poor survival. Expression of Notch-1 and its ligand, Jagged-1, is associated with the poorest survival, including ErbB-2-positive tumors. Trastuzumab plus chemotherapy is the standard of care for ErbB-2-positive breast cancer. A proportion of tumors are initially resistant to trastuzumab and acquired resistance to trastuzumab occurs in metastatic breast cancer and is associated with poor prognosis. Thus, we investigated whether Notch-1 contributes to trastuzumab resistance. ErbB-2-positive cells have low Notch transcriptional activity compared to non-overexpressing cells. Trastuzumab or a dual epidermal growth factor receptor (EGFR)/ErbB-2 tyrosine kinase inhibitor (TKI) increased Notch activity by 2- to 6-fold in SKBr3, BT474 and MCF-7/HER2-18 cells. The increase in activity was abrogated by a Notch inhibitor, gamma-secretase inhibitor (GSI) or Notch-1 small-interfering RNA (siRNA). Trastuzumab decreased Notch-1trade mark precursor, increased amount and nuclear accumulation of active Notch-1(IC) and increased expression of targets, Hey1 and Deltex1 mRNAs, and Hes5, Hey1, Hes1 proteins. Importantly, trastuzumab-resistant BT474 cells treated with trastuzumab for 6 months expressed twofold higher Notch-1, twofold higher Hey1, ninefold higher Deltex1 mRNAs and threefold higher Notch-1 and Hes5 proteins, compared to trastuzumab-sensitive BT474 cells. The increase in Hey1 and Deltex1 mRNAs in resistant cells was abrogated by a Notch-1 siRNA. Cell proliferation was inhibited more effectively by trastuzumab or TKI plus a GSI than either agent alone. Decreased Notch-1 by siRNA increased efficacy of trastuzumab in BT474 sensitive cells and restored sensitivity in resistant cells. Trastuzumab plus a GSI increased apoptosis in sensitive cells by 20-30%. A GSI alone was sufficient to increase apoptosis in trastuzumab-resistant BT474 cells by 20%, which increased to 30% with trastuzumab. Notch-1 siRNA alone decreased cell growth by 30% in sensitive and more than 50% in resistant BT474 cells. Furthermore, growth of both trastuzumab sensitive and resistant cells was completely inhibited by combining trastuzumab plus Notch-1 siRNA. More importantly, Notch-1 siRNA or a GSI resensitized trastuzumab-resistant BT474 cells to trastuzumab. These results demonstrate that ErbB-2 overexpression suppresses Notch-1 activity, which can be reversed by trastuzumab or TKI. These results suggest that Notch-1 might play a novel role in resistance to trastuzumab, which could be prevented or reversed by inhibiting Notch-1.

Do HER-2 positive metastatic breast cancer patients benefit from the use of trastuzumab beyond disease progression? A mono-institutional experience and systematic review of observational studies

Though preclinical evidence supports the protracted use of trastuzumab to reach sustained anti-tumor activity, the activity of trastuzumab beyond disease progression remains controversial in HER-2 over-expressing (HER-2+) metastatic breast cancer (MBC) patients. We retrospectively evaluated a total of 59 patients with HER-2 + MBC treated at our institution with trastuzumab-based therapies. Our results were added to those obtained in similar observational studies and summary estimates for overall response (OR) and clinical benefit (CB) to first and second trastuzumab-based lines were calculated. In our series of patients we observed an OR of 59.3% and 27% for first and second trastuzumab-based lines, respectively, with a corresponding CB of 83% and 62.2%, respectively. Time to first and second progression were 9.5 months and 6.7 months, respectively. The combined analysis showed an OR of 50% for first trastuzumab-based regimen and 21.2% for second trastuzumab-based line. The corresponding values for CB were 77.6% and 42.6%, respectively. A second trastuzumab-containing regimen beyond progression yields a considerable rate of OR and CB in HER-2 + MBC patients. Randomized trials are warranted.

Phase II trial of lapatinib for brain metastases in patients with human epidermal growth factor receptor 2-positive breast cancer

PURPOSE

One third of women with advanced human epidermal growth factor receptor 2 (HER-2)-positive breast cancer develop brain metastases; a subset progress in the CNS despite standard approaches. Medical therapies for refractory brain metastases are neither well-studied nor established. We evaluated the safety and efficacy of lapatinib, an oral inhibitor of epidermal growth factor receptor (EGFR) and HER-2, in patients with HER-2-positive brain metastases.

PATIENTS AND METHODS

Patients had HER-2-positive breast cancer, progressive brain metastases, prior trastuzumab treatment, and at least one measurable metastatic brain lesion. Patients received lapatinib 750 mg orally twice a day. Tumor response was assessed by magnetic resonance imaging every 8 weeks. The primary end point was objective response (complete response [CR] plus partial response [PR]) in the CNS by Response Evaluation Criteria in Solid Tumors (RECIST). Secondary end points included objective response in non-CNS sites, time to progression, overall survival, and toxicity.

RESULTS

Thirty-nine patients were enrolled. All patients had developed brain metastases while receiving trastuzumab; 37 had progressed after prior radiation. One patient achieved a PR in the brain by RECIST (objective response rate 2.6%, 95% conditional CI, 0.21% to 26%). Seven patients (18%) were progression free in both CNS and non-CNS sites at 16 weeks. Exploratory analyses identified additional patients with some degree of volumetric reduction in brain tumor burden. The most common adverse events (AEs) were diarrhea (grade 3, 21%) and fatigue (grade 3, 15%).

CONCLUSION

The study did not meet the predefined criteria for antitumor activity in highly refractory patients with HER-2-positive brain metastases. Because of the volumetric changes observed in our exploratory analysis, further studies are underway utilizing volumetric changes as a primary end point.

Overcoming treatment challenges in advanced breast cancer

OBJECTIVES

To describe new clinical findings, efficacy, and safety regarding the use of targeted agents in the treatment of HER2-positive metastatic breast cancer.

DATA SOURCES

Published research articles, abstracts, and clinical experience.

CONCLUSION

HER2-positive cases of breast cancer tend to be more aggressive and more likely to become resistant to therapy than HER2-negative tumors. The current standard approach to patients with HER2-positive metastatic breast cancer includes the use of trastuzumab. Because cellular mechanisms can arise that can block the efficacy of this approach (and result in clinical resistance), recent research has led to the development of lapatinib, a targeted therapy that can act on HER2 inside the cell to disrupt the signaling pathways thought to be part of tumorigenic mechanisms.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses should be aware of the treatment strategies for HER2-positive metastatic breast cancer and its limitations, which is essential for providing optimal nursing care.

Trastuzumab and gemcitabine as salvage therapy in heavily pre-treated patients with metastatic breast cancer

PURPOSE

In Her2-postive metastatic breast carcinoma, first-line trastuzumab-based therapy is well established; many centres continue antibody treatment beyond disease progression. In this trial, we evaluated the efficacy and safety of gemcitabine and trastuzumab after earlier exposure to anthracyclines, docetaxel and/or vinorelbine, and trastuzumab.

METHODS

Twenty-nine consecutive patients were included as eligible. Patients received gemcitabine at a dose of 1,250 mg/m2 on day one and eight, every 21 days. Trastuzumab was administered in three-week cycles. Clinical benefit rate (CBR; CR + PR + SD > or = 6 months) was defined as primary endpoint.

RESULTS

As of July 2007, all patients are evaluable for toxicity, and 26 for response. Earlier therapies consisted of trastuzumab (100%), anthracyclines (100%), vinorelbine (96.6%), docetaxel (72.4%), and capecitabine (72.4%). 19.2% of patients experienced PR, and SD > or = 6 months was observed in a further 26.9%, resulting in a CBR of 46.2%. Time to progression was median 3 months, and overall survival 17 months. Neutropenia (20.7%), thrombocytopenia (13.8%), and nausea (3.4%) were the only treatment-related adverse events that occurred with grade 3 or 4 intensity. Four patients (13.8%) developed brain metastases while on therapy.

CONCLUSIONS

While CBR was low when compared to trastuzumab-based first-line therapy, it is higher than what would be expected from gemcitabine monotherapy in a similar setting. Together with the favourable toxicity profile, this regimen appears to be a safe and potentially effective salvage therapy option in a heavily pre-treated population.

Targeted therapies in bladder cancer--an update

Intravesical immuno- and chemotherapy, surgery, and systemic chemotherapy are all critical elements in our management of patients with bladder cancer. Despite our advances with these modalities, we continue to seek newer treatment paradigms to improve patient outcome. Targeted therapy with novel agents directed at specific molecular pathways is a promising avenue to achieve such progress. This manuscript is based on a talk given at the Spring Session of the Society of Urologic Oncology in May 2006. Here, we focus on targeting growth factors and their receptors in bladder cancer. In particular, we summarize our own and others' ongoing basic science, translational, and clinical research in this field. Foremost in this line of study is the epidermal growth factor receptor (EGFR)-targeted therapy with small molecule inhibitors and monoclonal antibodies. We discuss the rationale for EGFR-directed therapy in bladder cancer. The clinical efficacy has been disappointing, and extensive work has been done to characterize molecular markers for predicting response. Some of our own preclinical findings related to platelet derived growth factor-beta (PDGFR-beta) and some background on ongoing clinical trials targeting human EGF receptor 2 (HER2) are summarized. Fibroblast growth factor 3 (FGFR3) offers promise as a potential target for therapy of both superficial and invasive disease. The role of FGFR3 mutations in bladder cancer is reviewed. Finally, we discuss the targeting of VEGF. Ultimately, it may be the use of multi-kinase inhibitors or the combination of different inhibitors to various targets that yields the best results.

American Society of Clinical Oncology 2007 update of recommendations for the use of tumor markers in breast cancer

PURPOSE

To update the recommendations for the use of tumor marker tests in the prevention, screening, treatment, and surveillance of breast cancer.

METHODS

For the 2007 update, an Update Committee composed of members from the full Panel was formed to complete the review and analysis of data published since 1999. Computerized literature searches of MEDLINE and the Cochrane Collaboration Library were performed. The Update Committee's literature review focused attention on available systematic reviews and meta-analyses of published tumor marker studies. In general, significant health outcomes (overall survival, disease-free survival, quality of life, lesser toxicity, and cost-effectiveness) were used for making recommendations. Recommendations and

CONCLUSIONS

Thirteen categories of breast tumor markers were considered, six of which were new for the guideline. The following categories showed evidence of clinical utility and were recommended for use in practice: CA 15-3, CA 27.29, carcinoembryonic antigen, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, urokinase plasminogen activator, plasminogen activator inhibitor 1, and certain multiparameter gene expression assays. Not all applications for these markers were supported, however. The following categories demonstrated insufficient evidence to support routine use in clinical practice: DNA/ploidy by flow cytometry, p53, cathepsin D, cyclin E, proteomics, certain multiparameter assays, detection of bone marrow micrometastases, and circulating tumor cells.

Trastuzumab plus vinorelbine or taxane chemotherapy for HER2-overexpressing metastatic breast cancer: the trastuzumab and vinorelbine or taxane study

BACKGROUND

The optimal trastuzumab-based chemotherapy regimen for HER2-overexpressing, metastatic breast cancer is not known. The trastuzumab and vinorelbine or taxane (TRAVIOTA) study was a prospective, multicenter, randomized trial that was designed to compare these regimens.

METHODS

Eligible patients had HER2-overexpressing, metastatic breast cancer and had received no prior chemotherapy for advanced disease. Patients were randomized 1:1 to receive either trastuzumab with weekly vinorelbine therapy or weekly taxane therapy (paclitaxel or docetaxel at the investigator's choice). Originally planned for 250 patients, the study was closed because of poor accrual with 81 evaluable patients, including 41 patients who received vinorelbine and 40 patients who received taxane.

RESULTS

Response rates were 51% and 40% for the vinorelbine/trastuzumab arm and the taxane/trastuzumab arm, respectively (Fisher exact test; P = .37). The median time to disease progression was 8.5 months and 6.0 months for the vinorelbine- and taxane-based arms, respectively (log-rank test; P = .09). Treatment with either regimen generally was well tolerated, yielding comparable rates of neurologic and gastrointestinal toxicity. Vinorelbine-based treatment was associated with more anemia and neutropenia and with 2 episodes of cardiotoxicity. Taxane-based therapy was associated with more dermatologic toxicity, myalgias, and fluid retention.

CONCLUSIONS

Both vinorelbine/trastuzumab and taxane/trastuzumab treatments were active as first-line therapy for HER2-positive, metastatic breast cancer and had comparable rates of efficacy and tolerability. The toxicities observed were the result of recognized side effects associated with each of the chemotherapy agents and schedules. These data can inform treatment decision making in this clinical setting.

Targeting the function of the HER2 oncogene in human cancer therapeutics

The year 2007 marks exactly two decades since human epidermal growth factor receptor-2 (HER2) was functionally implicated in the pathogenesis of human breast cancer (Slamon et al., 1987). This finding established the HER2 oncogene hypothesis for the development of some human cancers. An abundance of experimental evidence compiled over the past two decades now solidly supports the HER2 oncogene hypothesis. A direct consequence of this hypothesis was the promise that inhibitors of oncogenic HER2 would be highly effective treatments for HER2-driven cancers. This treatment hypothesis has led to the development and widespread use of anti-HER2 antibodies (trastuzumab) in clinical management resulting in significantly improved clinical antitumor efficacies that have transformed the clinical practice of oncology. In the shadows of this irrefutable clinical success, scientific studies have not yet been able to mechanistically validate that trastuzumab inhibits oncogenic HER2 function and it remains possible that the current clinical advances are a consequence of the oncogene hypothesis, but not a translation of it. These looming scientific uncertainties suggest that the full promise of the treatment hypothesis may not yet have been realized. The coming decade will see a second generation of HER2-targeting agents brought into clinical testing and a renewed attempt to treat HER2-driven cancers through the inactivation of HER2. Here, I review the development of treatments that target HER2 in the context of the HER2 oncogene hypothesis, and where we stand with regards to the clinical translation of the HER2 oncogene hypothesis.

Capecitabine and Trastuzumab in Heavily Pretreated Metastatic Breast Cancer

Purpose

In human epidermal growth factor 2 (HER-2)–positive advanced breast cancer, taxanes or vinorelbine plus trastuzumab are among the most widely applied options in the first-line setting. We evaluated the efficacy and tolerability of capecitabine plus trastuzumab after anthracycline and docetaxel or vinorelbine failure and prior trastuzumab exposure.

Patients and Methods

Forty consecutive patients were included. Capecitabine was administered at a dose of 1,250 mg/m2bid for 14 consecutive days in 3-week cycles, with dose modifications if necessary. Trastuzumab was administered every 3 weeks. Time to progression (TTP) was defined as primary end point. Response was evaluated every 3 months using International Union Against Cancer criteria.

Results

TTP was a median of 8 months, and overall survival was 24 months. No significant difference was found for second-line and beyond second-line treatment. A complete response (CR) was observed in 2.5%, partial response (PR) in 17.5%, stable disease lasting at least 6 months (SD) in 50%, resulting in a clinical benefit rate (CR + PR + SD ≥ 6 months) of 70%. Diarrhea (5%) and hand-foot syndrome (15%) were the only treatment-related adverse events that occurred with grade 3 or 4 intensity. Three patients (7.5%) developed brain metastases while receiving therapy.

Conclusion

Capecitabine plus trastuzumab appears to be an effective and safe option in a heavily pretreated population. Therefore, a direct comparison of this regimen with capecitabine monotherapy in this setting is warranted.

Bénéfice et risques potentiels de l'association du trastuzumab à la chimiothérapie et à la radiothérapie dans le cancer du sein non métastatique

Trastuzumab (Herceptin) is the first humanised monoclonal antibody targeting the HER2 antigen in breast cancer. HER2 receptor has been individualised 20 years ago. During the past 10 years, trastuzumab administration has radically modified the prognosis of the patients that are treated for HER2 positive breast cancer. Its efficacy has been demonstrated in the metastatic and adjuvant settings. While, trastuzumab based-regimens became the standard of care in the treatment of HER2/neu positive breast cancer, the optimal combination (concurrently or sequentially) to chemotherapy and radiation therapy is still unknown. Indeed, while the concurrent administration of trastuzumab and anthracyclines is not recommended because of a high risk of cardiac toxicity, there is no published data on the best sequence of trastuzumab and radiation therapy administration, particularly when internal mammary chain is involved. The benefit/risk ratio of the concurrent and sequential administration of trastuzumab with chemotherapy and radiation therapy will be discussed in this review.

Chromogenic and fluorescent in situ hybridization in breast cancer

Fluorescent (FISH) and chromogenic (CISH) in situ hybridization have recently become part of the diagnostic armamentarium of breast pathologists. HER2 gene testing by FISH and/or CISH has become an integral part of the diagnostic workup for patients with breast cancer. In this era of high throughput technologies, these techniques have proven instrumental for the validation of results from microarray-based comparative genomic hybridization and for the identification of novel oncogenes and tumor suppressor genes. Furthermore, FISH and CISH applied to tissue microarrays have expedited the characterization of genomic changes associated with specific breast cancer molecular subtypes and the identification of novel prognostic and predictive markers. In this review, we provide in this review a critical assessment of CISH and FISH and the impact of the analysis of amplification of specific oncogenes (eg, HER2, EGFR, MYC, CCND1, and FGFR1) and deletion of tumor suppressor genes (eg, BRCA1 and BRCA2) on our understanding of breast cancer.

HER2-positive advanced breast cancer

It is important when treating a patient who has advanced breast cancer to establish the biologic characteristics of the tumor. In addition to knowing the hormone receptor status (estrogen and progesterone), human epidermal receptor 2 (HER2) should be evaluated. The measurement of this parameter is essential to optimizing the systemic management. This article reviews the biology of HER2, testing for HER2, clinical studies evaluating HER2-based therapies, side effects (specifically cardiotoxicity), and strategies for HER2-based therapies.

Oral vinorelbine: role in the management of metastatic breast cancer

The treatment of advanced breast cancer is continually evolving, with the aim of improving the quality and duration of remission and, in some instances, survival. In this setting, the importance of quality of life cannot be underestimated, and growing attention is being paid to treatment convenience and compliance. New anticancer agents have improved efficacy, but for many of them, toxicity often remains a problem. Vinorelbine seems to represent both an active and a well tolerated treatment for metastatic breast cancer. In particular, the oral formulation has similar efficacy to that of the injectable formulation and has demonstrated generally favourable tolerability, with a high degree of acceptance by both patients and physicians. The availability of this and other novel, well tolerated and effective treatments provides greater potential to tailor treatment to meet individual patient needs and, therefore, also provide the potential to improve patient outcomes. Preliminary data suggest that oral vinorelbine may permit continued, effective chemotherapy when further parenteral therapy with more intensive and more toxic agents is considered inappropriate. Early findings also suggest that oral vinorelbine, when administered together with another new oral agent, capecitabine, may be a valid choice in metastatic breast cancer treatment. Furthermore, vinorelbine plus the monoclonal antibody trastuzumab, with or without oral capecitabine, appears to be another regimen that may be worthy of additional study in patients with human epidermal growth factor-2 positive advanced breast cancer.

A review of the use of trastuzumab (Herceptin®) plus vinorelbine in metastatic breast cancer

The combination of trastuzumab (Herceptin) and vinorelbine (Navelbine) in the treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) is valuable for several reasons. There is proven synergism of these agents in preclinical models, both agents are well tolerated and there is minimal overlapping toxicity. This article reviews clinical experience with trastuzumab and vinorelbine from phase II/III trials including >450 assessable patients. Results across the trials show objective response rates for the combination in the range of 44%-86% (51%-86% as first-line treatment) and a median duration of response of 10-17.5 months. Approximately 50% of patients experience grade 3/4 neutropenia, which is of short duration and manageable. Symptomatic cardiac events are infrequent (seven episodes of grade 3 toxicity across all trials). Overall, trastuzumab-vinorelbine combination therapy offers patients with HER2-positive MBC, an effective and well-tolerated treatment that is suitable for prolonged duration of use.

Development of real-time quantitative reverse transcription-PCR for Her2 detection in peripheral blood from patients with breast cancer

BACKGROUND

Amplification of the Her2neu oncogene is a well known indicator of poor prognosis in breast cancer patients. The implementation into the clinical setting of therapeutical strategies directly targeting the Her2neu gene product, has create the need for the development of non-invasive analytical techniques in order to monitoring minimal residual disease and response to the treatment.

METHODS

To detect the expression of Her2neu mRNA in peripheral blood, we developed a specific real-time quantitative reverse transcription-PCR (QPCR) assay. The analyses were performed on blood samples obtained from 30 breast cancer patients positive for Her2neu overexpression by immunohistochemical analysis (IHC), 10 breast cancer patients negative for Her2neu overexpression, and 24 healthy controls.

RESULTS

Her2neu positive tumors showed a significant increase in mRNA transcripts as compared with both healthy controls (n=24) and Her2neu negative patients (n=10). After establishing a cut-off value, 18 out of the 30 Her2neu positive patient scored positive for Her2neu expression, whereas only 1 out of the 10 Her2neu negative patients was weakly positive.

CONCLUSIONS

Her2neu QPCR is suitable method for Her2neu overexpression detection in peripheral blood from clinical samples of breast cancer patients. QPCR could be used to identify breast cancer patients with poor prognosis and for monitoring response to the therapy.

Achievements in systemic therapies in the pregenomic era in metastatic breast cancer

Over the last decades, the introduction of several new agents into clinical practice has significantly improved disease control and obtained some, albeit rare, survival benefits in metastatic breast cancer (MBC). Despite these results, the choice of treatment for the majority of patients is still empirically based, since the only two predictive factors with level 1 evidence for clinical use are hormonal receptor status for endocrine therapy and HER-2 status for trastuzumab therapy. Important improvements in the endocrine therapy of both pre- and postmenopausal women with hormone-responsive disease have been achieved. For premenopausal women, ovarian function suppression with luteinizing hormone-releasing hormone analogs combined with tamoxifen has become the standard treatment, although aromatase inhibitors plus ovarian function suppression are under evaluation. In postmenopausal patients, aromatase inhibitors have proved to be superior to standard endocrine therapies in either first- or second-line treatment and a novel antiestrogen compound, fulvestrant, has been introduced in clinical practice. Chemotherapy remains the treatment of choice for hormone unresponsive or resistant patients. Anthracyclines and taxanes have been used either alone or in combination as first-line chemotherapy, but with the more frequent use of these agents in the adjuvant setting, new standards are needed for first-line chemotherapy, and new and more efficacious treatments are required. In the subgroup of patients with tumors that overexpress HER-2, the use of trastuzumab alone or in combination with chemotherapy has modified the natural history of these tumors, even if only about one out of two patients obtains a clinical response. In this review we summarize the main achievements and the currently available treatment options for patients with MBC.

Improving the efficacy of trastuzumab in breast cancer

Although overexpression of human epidermal growth factor receptor 2 (HER2) protein, amplification of the gene or both are associated with poor prognosis in breast cancer, trastuzumab has clearly provided clinical benefits in metastatic breast cancer, adjuvant treatment settings and primary systemic therapy. However, even in those HER2 overexpressors, the majority of patients who achieve an initial response generally acquire resistance within 1 year. Therefore, it is critical to elucidate the mechanism of resistance and to search for better combination treatments with chemotherapeutic agents or other novel modalities. Here, we discuss both clinical and preclinical data regarding these issues.

Safety and activity of trastuzumab-containing therapies for the treatment of metastatic breast cancer: our long-term clinical experience (GOIM study)

BACKGROUND

Trastuzumab is widely used as the treatment of choice for HER2-positive metastatic breast cancer (MBC).

PATIENTS AND METHODS

Seventy patients, median age 57 years and range 31-81 years, were included in our retrospective analysis with the aim to evaluate safety and activity of trastuzumab-containing therapies.

RESULTS

We observed for first-line treatment response rate (RR) 41%, stable disease (SD) 47% and time to progression (TTP) 8 months (range 1-44). Corresponding numbers for second line were RR 23%, SD 62% and (TTP) 9 months (range 3-23) and beyond second line RR 22%, SD 78% and (TTP) 9 months (range 4-19). Overall survival was 19.2 months (3-62 months). The median cumulative dose of trastuzumab administrated was 5286 mg (464-17 940 mg). Trastuzumab was well tolerated. Median left ventricular ejection function (LVEF) at baseline was 62% and at the end of treatment was 59%. The more relevant adverse events consisted of an asymptomatic decrease in LVEF to 40% (baseline 60%) and a grade 3 symptomatic increase in bilirubin.

CONCLUSION

Trastuzumab-containing therapies in MBC show a good safety and toxicity profile and a remarkable activity even in heavily pretreated women. Patients should benefit from continued trastuzumab therapy, as shown by the maintenance of (TTP) even beyond second-line treatment.

Perspective of trastuzumab treatment

Trastuzumab (Herceptin) has many benefits for metastatic breast cancer patients with HER2 overexpression/amplification. Trastuzumab alone or trastuzumab in combination with chemotherapy regimens are standard treatment worldwide as first line therapy for metastatic breast cancer patients with HER2 overexpression/amplification. Furthermore, an international collaboration for adjuvant trastuzumab trials showed last year that trastuzumab treatment improves disease-free and overall survival after or in combination with adjuvant chemotherapy. However, there are many uncertain issues concerning trastuzumab adjuvant and metastatic treatment, such as treatment beyond disease progression (PD), combination with hormone therapy, duration of adjuvant treatment, and cardiac safety of long term treatment.

Phase II Study of Neoadjuvant Docetaxel, Vinorelbine, and Trastuzumab Followed by Surgery and Adjuvant Doxorubicin Plus Cyclophosphamide in Women With Human Epidermal Growth Factor Receptor 2–Overexpressing Locally Advanced Breast Cancer

Purpose

To evaluate the combination of docetaxel, vinorelbine, and trastuzumab as neoadjuvant therapy for human epidermal growth factor receptor 2 (HER2) –overexpressing breast cancer.

Patients and Methods

Patients with stage IIB or III breast cancer, including inflammatory disease, and HER2 overexpression (determined by fluorescent in situ hybridization) were treated with six cycles of docetaxel 60 mg/m2 and vinorelbine 45 mg/m2 administered every 14 days with granulocyte colony-stimulating factor and quinolone prophylaxis. Trastuzumab was administered as a 4 mg/kg loading dose followed by 2 mg/kg weekly for 12 weeks. The primary efficacy end point was pathologic complete response (pCR) in the breast.

Results

Of 31 enrolled patients, 68% had T3 or T4 tumors and 90% were clinically node positive. Twelve patients (39%; 95% CI, 21.6% to 55.9%) achieved pCR in the breast and lymph nodes and 14 patients (45%; 95% CI, 27.6% to 62.7%) achieved pCR in the breast alone, and 19 patients (61%; 95% CI, 44.1% to 78.4%) were node negative after neoadjuvant therapy. Clinical response was documented in 29 patients (94%; 95% CI, 78.6% to 99.2%) with 26 complete responses (84%; 95% CI, 70.9% to 96.8%). The most commonly reported grade 3/4 toxicities were neutropenia (97%), febrile neutropenia (22%), anemia (6%), mucositis/stomatitis (6%), constipation (6%), and skin rash (6%).

Conclusion

With clinical response and pCR rates of 94% and 39%, respectively, docetaxel, vinorelbine, and trastuzumab is a highly active neoadjuvant therapy for HER2-overexpressing locally advanced breast cancer. Although well tolerated overall, significant febrile neutropenia was observed despite prophylactic measures; therefore, evaluating a similar regimen using lower docetaxel and/or vinorelbine doses is warranted.