Comparison of HER-2 status between primary breast cancer and corresponding distant metastatic sites

HER-2 (c-erbB-2) test update: present status and problems

HER-2 tests are routinely used for the identification of patients with metastatic breast cancer that is potentially responsive to trastuzumab (herceptin) therapy. Recently, convincing data have been published with regard to the efficacy of trastuzumab as a drug for neoadjuvant therapy or adjuvant therapy for operable primary breast cancer that overexpresses HER-2. It is also noteworthy that a the St. Gallen International Consensus Conference 2005, HER-2 protein overexpression or HER-2 gene amplification has been included as an indicator for higher risk of recurrence for both node-negative and node-positive breast cancers. To measure the HER-2 level, the worldwide consensus appears to be that immunohistochemistry (IHC) should be performed first and, if the results of IHC are uncertain, fluorescence in situ hybridization (FISH) should be performed later, although some investigators argue that FISH should be performed first. These tests should be performed in strict adherence to existing instructions. Quality control is of utmost importance when performing HER-2 tests, both internal and external, for routine diagnosis and in clinical protocol studies.

Bortezomib (PS-341, Velcade) increases the efficacy of trastuzumab (Herceptin) in HER-2-positive breast cancer cells in a synergistic manner

BACKGROUND

Preclinical and clinical studies have shown that the proteasome inhibitor bortezomib (PS341, Velcade) is highly effective when combined with chemotherapeutic agents. The value of trastuzumab (Herceptin) in HER-2-positive (3+ score by immunohistochemistry or fluorescence in situ hybridization positive) breast cancer is also known; however, the response rate is <40% for metastatic breast cancer. These two pharmacologic agents prevent nuclear factor-kappaB (NF-kappaB) activation and induce nuclear accumulation of the cyclin-dependent kinase inhibitor p27(kip1), suggesting that combining bortezomib with trastuzumab could increase trastuzumab efficacy.

METHODS

Drug cytotoxicity, both individually and together, and drug effects on p27 localization and NF-kappaB activation were investigated on four breast cancer cell lines: SKBR-3 (HER-2+++), MDA-MB-453 (HER-2++), HER-2-transfected MCF-7 (HER-2+++), and MCF-7 (HER-2-).

RESULTS

Bortezomib induced apoptosis in HER-2-positive and HER-2-negative breast cancer cells in a dose- and time-dependent manner. Together, these drugs induced apoptosis of HER-2++/+++ cells at low concentrations, which had no effect when used alone, indicating there was a synergistic effect. Sequential treatment (trastuzumab then bortezomib) induced either necrosis or apoptosis, depending on the trastuzumab preincubation time. Susceptibility to bortezomib alone and the drug combination correlated with NF-kappaB activity and p27 localization.

CONCLUSIONS

The addition of bortezomib to trastuzumab increases the effect of trastuzumab in HER-2+++/++ cell lines in a synergistic way. This effect likely results from the ability of these two drugs to target the NF-kappaB and p27 pathways. The potential clinical application of this drug combination is under current evaluation by our group in a phase 1 clinical trial.

Different Expression of HER2/neu Oncogene in Breast Carcinoma and in Liver Metastasis. Description of a Case

We report the clinical, morphological and molecular findings regarding a 37-year-old woman with breast cancer metastatic to the liver and describe the different expression of a tumor marker in the primary and secondary lesions and the singular responsiveness to treatment. The patient suffered from a carcinoma of the left breast with metastasis to the liver. High HER-2 protein expression assessed by immunohistochemistry and HER-2/neu amplification determined by FISH were present in the primary tumor, while the liver metastasis showed a lower value of HER-2 protein (2+) and absence of HER-2/neu amplification. The patient was treated with chemotherapy (epirubicin and paclitaxel) followed by trastuzumab and docetaxel. After 5 months, at the completion of chemo-immunotherapy, liver ultrasonography showed a further hepatic response. A second biopsy was performed on the residual liver nodule: immunohistochemistry revealed negative (1+) HER-2 expression and FISH confirmed that the HER-2/neu gene was not amplified. The different amplification of HER-2 and expression of its protein in primary and metastatic carcinoma could be important for planning adequate treatment.

HER-2/neu genotype of breast cancer may change in bone metastasis

The genotype of breast cancer (BRC) is considered to be relatively stable during tumor progression, accordingly, determination of the estrogen receptor and HER-2/neu status is currently based on the primary tumor. However, recent data suggest that the gene expression profile of the metastatic lesion can be different compared to that of the primary BRC. Accordingly, it is possible that the HER-2/neu status is different in the metastatic lesion and the primary BRC. Since the bone is the most frequent metastatic site during the progression of BRC, we have analyzed the HER-2/neu status of 48 bone metastatic BRC cases by immunohistochemistry and fluorescent in situ hybridization, and it was possible to compare it to the primary site in 23 cases. The frequency of HER-2/neu amplification of BRC in the primary tumors was found to be 17.4% compared to 10.5% in bone metastases. Half of BRC cases with HER-2/neu amplification lost this genotype in bone metastases (4/23 versus 2/23, respectively) and even in the 2 cases where HER-2/neu amplification was retained in the metastases, the copy number was found to be decreased compared to the primary tumor. Based on our data and previous reports in the literature, we suggest to perform HER-2/neu testing both on primary tumor and samples obtained from BRC metastases, at least in case of primary tumors with HER-2/neu amplification, before introduction of HER-2/neu-targeting therapy.

Beta-catenin nuclear expression correlates with cyclin D1 expression in primary and metastatic synovial sarcoma: a tissue microarray study

CONTEXT

The association between aberrant (nuclear) beta-catenin expression and cyclin D1 accumulation has been demonstrated in diverse neoplasms. In synovial sarcoma (SS), aberrant beta-catenin expression has prognostic relevance, but the association with cyclin D1 has not been established. The SYT-SSX fusion protein, unique to SS, may independently increase cyclin D1.

OBJECTIVE

To determine whether nuclear beta-catenin is associated with cyclin D1 overexpression in SS and whether primary and metastatic SS differ in the expression of these markers.

DESIGN

We incorporated 82 tumors initially diagnosed as SS into a tissue array. Fluorescence in situ hybridization with custom probes was used to select t(X;18) positive tumors. Clinical data, tumor type and outcome were tabulated. The tumors were tested for the association between nuclear beta-catenin and cyclin D1 immunostaining. Primary and metastatic tumors were compared.

RESULTS

Fifty-one tumors (41 primary and 10 metastatic) from 43 patients demonstrated t(X;18). Cyclin D1 staining was identified in 21 (59%) primary and 8 (80%) metastatic tumors, respectively, and nuclear beta-catenin in 24 (41%) primary and 7 (70%) metastatic tumors, respectively. No significant difference was noted between primary and metastatic tumors with respect to the above markers. The presence of nuclear beta-catenin showed a significant association with cyclin D1 expression (P < .001). A small number of cyclin D1 cases were negative for nuclear beta-catenin but positive for phosphorylated Akt.

CONCLUSIONS

Increased cyclin D1 in SS may be driven by abnormally expressed beta-catenin, similar to other neoplasms. The pattern of expression of these markers is established early during tumorigenesis.

Tumor Imaging Using a Picomolar Affinity HER2 Binding Affibody Molecule

The detection of cell-bound proteins that are produced due to aberrant gene expression in malignant tumors can provide important diagnostic information influencing patient management. The use of small radiolabeled targeting proteins would enable high-contrast radionuclide imaging of cancers expressing such antigens if adequate binding affinity and specificity could be provided. Here, we describe a HER2-specific 6 kDa Affibody molecule (hereinafter denoted Affibody molecule) with 22 pmol/L affinity that can be used for the visualization of HER2 expression in tumors in vivo using gamma camera. A library for affinity maturation was constructed by re-randomization of relevant positions identified after the alignment of first-generation variants of nanomolar affinity (50 nmol/L). One selected Affibody molecule, Z(HER2:342) showed a >2,200-fold increase in affinity achieved through a single-library affinity maturation step. When radioiodinated, the affinity-matured Affibody molecule showed clear, high-contrast visualization of HER2-expressing xenografts in mice as early as 6 hours post-injection. The tumor uptake at 4 hours post-injection was improved 4-fold (due to increased affinity) with 9% of the injected dose per gram of tissue in the tumor. Affibody molecules represent a new class of affinity molecules that can provide small sized, high affinity cancer-specific ligands, which may be well suited for tumor imaging.

Comparison of HER2 status between primary tumor and disseminated tumor cells in␣primary breast cancer patients

BACKGROUND

The persistence of disseminated tumor cells (DTC) in bone marrow (BM) of breast cancer patients is associated with poor prognosis. Preliminary studies indicated that these patients might benefit from secondary adjuvant targeted therapy. HER2 protein is suggested as one of the most promising targets. The aims of this study were (1) to determine the HER2 status of DTC in BM of breast cancer patients and (2) to compare the HER2 status of DTC and corresponding primary tumors.

METHODS

BM aspirates from 137 primary breast cancer patients were included into the study. A double staining procedure was used for the identification of cytokeratin-positive (CK)/HER2 positive cells. HER2 status of the primary tumor was immunohistochemically assessed by the HERCEP-test.

RESULTS

In 46 of 137 (34%) breast cancer patients CK-positive cells were detectable in BM. DTC with HER2 positivity were found in 20 (43%) of these patients. The HER2 expression on DTC was heterogeneous in 7 of 17 (41%) patients. Concordance rate of HER2 status between primary tumor and DTC was 62%. In 12 of 20 patients with HER2 negative tumors HER2 positive DTC were detected.

CONCLUSIONS

HER2 positive DTC can be detected in patients with HER2 negative primary tumors. Therefore, the antigenic profile of DTC may be considered for treatment decision since these patients might actually benefit from trastuzumab. However, the HER2 overexpression on DTC is heterogeneous in individual patients which may reduce the efficacy of an immunotherapy based strategy directed against HER2-antigen only.

Selective proapoptotic activity of a secreted recombinant antibody/AIF fusion protein in carcinomas overexpressing HER2

Apoptosis-inducing factor (AIF) represents a caspase-independent apoptotic pathway in the cell, and a mitochondrial localization sequence-truncated AIF (AIFDelta1-120) can be relocated from the cytoplasm to the nucleus and exhibit a constitutive proapoptotic activity. Here, we generated a chimeric immuno-AIF protein, which comprised an HER2 antibody, a Pseudomonas exotoxin translocation domain and AIFDelta1-120. Human Jurkat cells transfected with the immuno-AIF gene could express and secrete the chimeric protein, which selectively recognized HER2-overexpressing tumor cells and was endocytosed. Subsequent cleavage of truncated AIF from immuno-AIF and its release from the internalized vesicles resulted in apoptosis of tumor cells. Intramuscular injection of the immuno-AIF gene caused significant suppression of tumors and substantially prolonged mice survival in an HER2-overexpressing xenograft tumor model. Our study demonstrates the feasibility of the immuno-AIF gene as a novel approach to treating cancers that overexpress HER2.

Pharmacodiagnostic testing in breast cancer: focus on HER2 and trastuzumab therapy

Pharmacogenomics is defined as research into inherited genetic variations that determine an individual's response to therapeutic agents. In oncology, pharmacogenomics based on somatic molecular alterations inherited by subsequent cancer cell generations forms the basis of molecular targeting of novel therapeutic agents. What has emerged from clinical experience with such agents is the need for appropriate pharmacodiagnostic approaches to ensure the drugs are correctly targeted. Given the broad range of pharmacogenomic agents currently under evaluation for cancer therapy, it appears that a rapid extension of pharmacodiagnostic profiling will be required in the next 5-10 years, if not sooner. If this is to be successfully achieved, lessons learned in the past, particularly during the development of HER2 (ERBB2) testing for directing trastuzumab therapy in breast cancer, may provide a valuable framework for the development of future pharmacodiagnostic assays system. This article reviews the biological and clinical rationale for targeting breast cancer with trastuzumab and the steps taken to validate and improve pharmacodiagnostic procedures for testing tumor HER2 protein expression and HER2 gene amplification. Attention is given to quality assurance and reproducibility of testing approaches and the optimal selection of patients for response to trastuzumab. This approach serves as a paradigm for the future development of pharmacodiagnostic tests in oncology.

HER2 status is an important biomarker in guiding personalized HER2 therapy

The human epidermal growth factor receptor (HER)2 oncoprotein has emerged as an important cellular target for the development of a variety of new cancer therapies. The method used to define the HER2 status is a major factor in determining who will receive these targeted therapies. The HER2 status can be determined by using either tissue tests to look at the primary tumor cells, or an enzyme-linked immunosorbent assay (ELISA) that measures the circulating levels of the extracellular portion of HER2 protein. Tissue test (immunohistochemistry and fluorescence in situ hybridization) results indicate that approximately 20–30% of patients with primary breast cancer have a HER2-positive tumor, whereas ELISA results demonstrate that an average of 45% (range: 23–80%) of metastatic breast cancer (MBC) patients can have an abnormally high (> 15 ng/ml) serum HER2 level, which is evidence that a HER2-positive tumor is present. Published studies show that the HER2 status of a breast cancer patient can differ both by the test method used and the time at which HER2 status is assessed. In this review, data will be shown that demonstrates that not all HER2 test results obtained from the primary breast cancer are correct, and that there is a population of patients categorized as HER2 negative by tissue tests that, in fact, have HER2-positive tumors. This observation has important therapeutic implications for breast cancer patients with HER2-positive tumors that are classified as HER2 negative, since they are not eligible for anti-HER2 therapy, such as trastuzumab. If a patient is found to have an elevated (> 15 ng/ml) serum HER2 level in MBC, then either the original tumor should be re-evaluated for HER2 status, or a metastatic lesion should be tested for HER2 positivity, to determine if the patient is eligible for anti-HER2 therapy. Studies have also shown that lack of adequate validation of a testing method can result in false conclusions concerning the HER2 status. If the goal of personalized medicine is to deliver the right treatment to the right patient at the right time then we need to ensure the validity of all test methods, regardless of whether they are for research purposes or are registered as in vitro diagnostics. In the case of establishing HER2 status, it takes more than one type of test to identify patients with HER2-positive tumors. It is highly likely that the introduction of additional targeted drugs to growth factor receptors or to angiogenesis targets will take a variety and combinations of tests to tailor the most appropriate therapy to the patient.

Comparison of HER-2 overexpression in primary breast cancer and metastatic sites and its effect on biological targeting therapy of metastatic disease

HER-2 overexpression, a predictive marker of tumour aggressiveness and responsiveness to therapy, occurs in 20-30% of breast cancer. Although breast cancer is a heterogeneous disease, HER-2 measurement is carried out in primary tumour. This study aims to evaluate HER-2 overexpression in primary and metastases and its effect on treatment decisions. Biopsies from primary breast cancer and corresponding metastases from 58 patients were studied. HER-2 overexpression was evaluated immunohistochemically in all primary and metastatic sites. Positive overexpression in primary and/or metastases was confirmed by fluorescence in situ hybridisation (FISH). Discordance in HER-2 overexpression between primary and metastatic sites was 14% (eight of 58 patients). Concordance was found in 50 (86%) of patients (95% CI: 77-95). In one patient (2%), HER-2 was negative in metastasis but positive in primary. In seven (12%) patients, HER-2 was positive in metastases and negative in primary (95% CI: 3.7-20), and three of them responded to trastuzumab. Gene amplification by FISH was found in all cases with HER-2 positive (+2 and +3) by immunohistochemistry. Our data suggest that a possible discordance of HER-2 overexpression between primary and metastases should be considered when making treatment decisions in patients with primary HER-2-negative tumours.

Concordance of the hormone receptors and correlation of HER-2/neu overexpression of the metachronous cancers of contralateral breasts

The primary objective of this study was to evaluate the relative prevalence of estrogen receptor-negative contralateral breast cancer to the first primary cancer and to assess the correlation between the relative overexpression of HER-2/neu in the first primary cancer and contralateral breast cancer. A total of 144 women diagnosed with cancers in contralateral breasts were identified from the Henry Ford Health System tumor registry. Data were retrieved from electronic databases and medical records. Women were dichotomized into users and nonusers of tamoxifen. Hormone receptors were scored as positive or negative. HER-2/neu overexpression, assessed by immunohistochemistry, was scored as 0, 1(+), 2(+), or 3(+). Concordance between hormone receptors of the two cancers was low (kappa = 0.27, p = 0.06). Stratification of women by tamoxifen therapy yielded an almost fivefold increase in the proportion of estrogen receptor-negative cancers among the users, while the proportion of cancers expressing no estrogen receptor remained the same among the nonusers (39.6% versus 40.6%). Matched, archived, paraffin-embedded specimens of the first and contralateral breast cancers were available for 57 women. The correlation between the relative overexpression of HER-2/neu between the first primary and the contralateral breast cancer was 0.4 (p = 0.002). The higher prevalence of estrogen receptor-negative contralateral breast cancer among tamoxifen users concurs with previous reports. The biological mechanism for this observation is not understood; however, it has been proposed that tamoxifen inhibits the proliferation of estrogen receptor-positive breast cancer cells, while estrogen receptor-negative cells may continue to grow because of selective pressure. The correlation between HER-2/neu overexpression in the matched first primary and contralateral breast cancers was statistically significant, suggesting that the diagnosis of HER-2/neu overexpression in contralateral breast cancer is associated with HER-2/neu overexpression in the first primary cancer.

Polysomy 17 in HER-2/neu Status Elaboration in Breast Cancer: Effect on Daily Practice

PURPOSE

To assess the effect of chromosome 17 copy number on HER-2/neu status determination in breast cancers.

EXPERIMENTAL DESIGN

HER-2/neu gene copy and chromosome 17 centromere numbers were evaluated on 893 breast carcinomas using double color fluorescence in situ hybridization (FISH). The net and chromosome 17 corrected (ratio) HER-2/neu copy numbers were compared and related to immunohistochemistry done according to the Food and Drug Administration (FDA)-approved scoring system (0, 1+, 2+, and 3+) as a first screening step in 584 cases.

RESULTS

When a ratio > or = 2 was considered as criterion for FISH positivity, 49.3% (440 of 893) of cases showed amplification versus 56.2% (502 of 893) by using a net HER-2/neu gene copy number >4 as a alternative criterion; 14.8% (67 of 453) of cases having a ratio <2 had a net HER-2/neu gene copy number >4 and 1.1% (5 of 440) with a ratio > or = 2 had a net HER-2/neu gene copy number <4. Among discordant cases, 88.8% (64 of 72) were polysomic (>2.25 chromosomes 17/cell) and among polysomic cases, 12.8% (40 of 312) of the low polysomic (2.26-3.75 chromosomes 17/cell) and 36.9% (24 of 65) of the highly polysomic (>3.75 chromosomes 17/cell) cases showed discordance. In cases with a ratio <2, polysomy 17 incidences were 85.7% (6 of 7) in IHC 3+, 42.4% (79 of 186) in IHC 2+, 33.3% (15 of 45) in IHC 1+, and 29.1% (16 of 55) in IHC 0.

CONCLUSION

A net increase in HER-2/neu gene copy number consecutive to polysomy 17 in the absence of specific gene amplification might lead to a strong protein overexpression in a small subset of breast carcinomas. HER-2/neu status determination by FISH is dependent on the criterion considered for positivity in clinical practice.

HER2/neu expression and amplification in non-small cell lung cancer prior to and after neoadjuvant therapy

BACKGROUND

Expression and amplification of the HER2/neu protooncogene was analyzed in locally advanced NSCLC in a multimodality therapy approach in order to obtain information on the predictive value of HER2/neu for success or failure of neoadjuvant therapy.

METHODS

In the scope of a prospective randomized phase III-trial, tumor tissue of pre-therapeutically obtained mediastinal lymph node biopsies (n=105) and corresponding post-surgical resection specimens (n=44) was analyzed by means of immunohistochemistry (DAKO-Hercep-Test) and fluorescence in situ hybridization (FISH). In 58 of 105 patients with metastatic mediastinal lymph node disease the extent of therapy-induced tumor regression could be established.

RESULTS

Concerning HER2/neu expression, 16 lymph node biopsies (15.2%) showed 1+, 2+, or 3+ results. Five of these cases revealed amplification in FISH analysis (4.8%). In 44 corresponding resection specimens, Hercep-Test showed 1+, 2+, or 3+ results in 13 tumors (29.5%). Two of these patients revealed HER2/neu amplification in FISH analysis (4.5%). In patients with HER2/neu expressing tumors a trend towards a less extensive therapy-induced tumor regression could be demonstrated. When comparing pre-therapy and post-surgical results, there was a weak trend towards a selection of HER2/neu expressing tumor tissue in the course of neoadjuvant therapy.

CONCLUSIONS

Only a limited subcollective of locally advanced NSCLC meets the biological requirements for anti-HER2/neu therapy. HER2/neu positive tumors appeared to be relatively resistant to chemotherapy and radiation treatment, none of these cases having a pathological complete or at least subtotal response in the corresponding resection specimens. This observation requires confirmation in large randomized controlled studies.

Re-evaluation of HER2 status in metastatic breast cancer and tumor-marker guided therapy with vinorelbine and trastuzumab

BACKGROUND

HER2 is overexpressed in 20-30% of breast cancers. Compared to chemotherapy alone, chemotherapy with trastuzumab improves clinical outcome in patients with HER2-positive metastatic breast cancer (MBC). In general, HER2 status in a primary lesion predicts the status of metastases, so that biopsy of metastatic lesions appears unnecessary.

CASE REPORT

A 39-year old woman was diagnosed with primary breast cancer in November 2000. Using the method and scoring system of the DAKO Hercep Test, the tumor has shown low HER2 expression (DAKO score 1+). After failure of several chemotherapy regimens for metastatic disease (liver, skeletal), the patient underwent CT-guided needle biopsy of the liver which showed HER2 positive adenocarcinoma (DAKO score 3+). In consequence, the patient was treated with vinorelbine (30 mg/m2 d1,8,15 q4w) and trastuzumab (4 mg/kg loading dose, 2 mg/kg weekly). During a treatment period of 4 months imaging results as well as tumor marker kinetics indicated an excellent response with sustained decrease of tumor markers. A retrospective analysis of the HER2 shed antigen in metastatic stage revealed excessively increased serum levels and supports HER2 overexpression observed in liver metastasis. The kinetics of the HER2 shed antigen during therapy for metastatic disease were found to be in phase with the kinetics of CEA and CA15-3.

CONCLUSION

This case report demonstrates that re-evaluation of the HER2 status may be helpful in single patients not sufficiently responding to treatment of metastatic disease. Determination of HER2 overexpression may be facilitated by a determination of the HER2 shed antigen level in peripheral blood.

Stability of the HER2 gene after primary chemotherapy in advanced breast cancer

We investigated whether alterations of the Her2 gene could be detected in breast cancer samples following primary chemotherapy in advanced breast cancer. The prospective study involved 23 patients with stage-II, -III or -IV breast cancer. All patients were treated with two to six cycles of fluorouracil-epirubicin and/or cyclophosphamid/epi-docetaxel. The Her2 protein and gene were assessed both on core needle biopsies prior to and on surgical specimens after completing chemotherapy using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) methods. Estrogen and progesterone receptors (ER/PR) were also determined on both samples using IHC. Her2 status was modified in eight patients using IHC (35%) and in three patients using FISH (13%). Changes in ER/PR expression were detected in seven patients (30%). Our data suggest that alterations of the Her2 gene can occur, although not usually after primary or neoadjuvant chemotherapy. However, changes in ER/PR status seem to be a more common event; thus, both can lead to different therapeutic options. Intratumoral heterogeneity as well as sampling variations can contribute to modification of the Her2 status after primary chemotherapy.

Comparison ofHER-2 status determined by fluorescence in situ hybridization in primary and metastatic breast carcinoma

BACKGROUND

Accurate assessment of HER-2 status is necessary prior to anti-HER-2 antibody (trastuzumab) therapy for metastatic breast carcinoma. However, controversy exists regarding whether to assess HER-2 status in the primary tumor or in metastatic lesions. It is also unclear whether HER-2 status can change during disease progression or after chemotherapy.

METHODS

Breast carcinoma samples from 60 women with known HER-2 status in both primary tumors and paired metastases (locoregional disease, n = 43 patients; distant disease, n = 17 patients) were reviewed retrospectively. Thirty-two patients underwent chemotherapy before their metastatic lesions were sampled, including 18 patients who received neoadjuvant chemotherapy and 14 patients who received adjuvant chemotherapy. The HER-2 gene was examined by fluorescence in situ hybridization either in paraffin-embedded tissue samples (48 primary tumors and 9 metastatic tumors) or in fine-needle aspirates (12 primary tumors and 51 metastatic tumors). HER-2 gene amplification was defined as a HER-2:chromosome 17 signal ratio >/= 2.0.

RESULTS

The HER-2 status of primary and metastatic tumors agreed in 58 of 60 patients (97%), including 18 (30%) amplified tumors and 40 (67%) nonamplified tumors. A discrepancy in HER-2 status was observed in specimens from two patients in which HER-2 amplification was detected in the primary tumor but not the metastatic tumors. In one patient, three foci of tumor nodules were found in the same breast; the HER-2 status was assessed in only one of them, which showed amplification; however, HER-2 amplification was not detected in the axillary lymph node metastasis. In another patient, the HER-2 gene was amplified in the primary tumor but not in the liver metastasis. No metastases showed HER-2 amplification without amplification in the primary tumor. Locoregional and distant metastases demonstrated similar concordance rates with their corresponding primary tumors (98% and 94%, respectively). Complete concordance of HER-2 status was found between primary tumors prior to chemotherapy and metastases that were sampled after chemotherapy.

CONCLUSIONS

The HER-2 status in breast carcinoma generally was stable during metastasis, whether to locoregional or distant sites. Chemotherapy did not modify the HER-2 status in metastatic lesions. Therefore, HER-2 amplification can be evaluated reliably in material from either primary or metastatic tumors in most patients. Further study with larger series is warranted to elucidate the significance of discordant results.

Beyond lymph node staging: molecular predictors of outcome in breast cancer

This article briefly reviews the exciting, yet unproven, reports of alternate methods of predicting outcomes in breast cancer and highlights new molecular methods of diagnosing, classifying, and treating this disease. The author starts by reviewing well-known factors in breast cancer with which all alternate methods of staging and predicting outcomes must be compared prospectively.

Improving patient care through molecular diagnostics

Traditional cancer diagnostic techniques include assessment of histologic appearance, identification of specific tumor subtypes, tumor grading, assessment of lymph node status, and presence of metastasis. These are useful for initial evaluation, but are limited in their ability to predict response to treatment and/or risk of experiencing adverse events to particular treatments. Recently, there has been considerable progress in molecular diagnostics in this area. Using molecular-based technologies, it is now possible to identify some patients with an inherited risk of developing breast cancer, and to more accurately assess the prognosis of those who already have developed the disease. Various techniques are also available or under investigation to help select patients who are most likely to respond to certain types of treatment. At present, this includes diagnostic tests to identify single tumor markers for which specific therapies are available, such as estrogen receptor and HER2. Diagnostic systems that allow simultaneous assessment of multiple markers, such as DNA microarrays and proteomics, are currently being validated. The use of these systems will allow further development of customized therapies directed toward the particular molecular defects in a given cancer.

HER2 expression in cervical cancer as a potential therapeutic target

BACKGROUND

Trastuzumab, a humanized monoclonal antibody against the HER2 receptor is currently being used in breast and other tumor types. Early studies have shown that a variable proportion of cervical carcinoma tumors overexpress the HER2 receptor as evaluated by diverse techniques and antibodies. Currently it is known that a tumor response to trastuzumab strongly correlates with the level of HER2 expression evaluated by the Hercep Test, thus, it seems desirable to evaluate the status of expression of this receptor using the FDA-approved Hercep Test and grading system to gain insight in the feasibility of using trastuzumab in cervical cancer patients.

METHODS

We analyzed a series of cervical cancer cell lines, the primary tumors of 35 cases of cervical cancer patients and four recurrent cases, with the Hercep Test in order to establish whether this tumor type overexpress HER2 at level of 2+/3+ as trastuzumab is currently approved for breast cancer having such level of expression.

RESULTS

The results indicate that only 1 out of 35 primary tumors cases overexpress the receptor at this level, however, two out of four recurrent tumors that tested negative at diagnosis shifted to Hercep Test 2+ and 3+ respectively.

CONCLUSIONS

The low frequency of expression in primary cases suggests that trastuzumab could have a limited value for the primary management of cervical cancer patients, however, the finding of "conversion" to Hercep Test 2+ and 3+ of recurrent tumors indicates the need to further evaluate the expression of HER2 in the metastatic and recurrent cases.

HER2 and Central Nervous System Metastasis in Patients with Breast Cancer

We report a case of a patient who developed a central nervous system (CNS) metastasis 17 months after surgery and adjuvant therapy for stage II breast cancer. The HER2 status of the primary tumor as determined by immunohistochemistry (IHC) was 1+, and fluorescence in situ hybridization (FISH) performed retrospectively showed a borderline-negative result (ratio, 1:9), although HER2 amplification was present in a minority of breast cancer cells. By contrast, the HER2 status of the CNS metastasis was positive by IHC (3+) and FISH (ratio, 3:7). This report discusses the possibility that, for metastatic invasion into the CNS, clonal selection may occur, favoring HER2-positive cell clones.

HER-2/neu as a Predictive Marker in a Population of Advanced Breast Cancer Patients Randomly Treated Either with Single-agent Doxorubicin or Single-agent Docetaxel

PURPOSE

To evaluate the predictive value of HER-2 in a population of advanced breast cancer patients randomly treated either with single-agent doxorubicin (A) or with single-agent docetaxel (T).

EXPERIMENTAL DESIGN

Patients from this study participated in a phase III clinical trial in which doxorubicin or docetaxel was administered for advanced disease. HER-2 was evaluated by IHC. In all positive cases, FISH was used to confirm the HER-2 positive status. The different cohorts of patients identified by HER-2 were examined to assess a possible relationship between HER-2 status and treatment effect.

RESULTS

Tumor samples were available for 176 of the 326 patients entered in the clinical trial (54%). HER-2 positivity was observed in 20% of the study population. A statistically significant interaction was found between response rates to the study drugs and HER-2 status, with HER-2 positive patients deriving the highest benefit from the use of T (odds ratio for HER-2 positive patients treated with T = 3.12 (95% CI 1.11-8.80), p = 0.03). The interaction between HER-2 and response rates to A and T was also confirmed by a multivariate analysis. No statistically significant interaction was found between HER-2 and drugs efficacy evaluated in terms of time to progression and overall survival, although in the HER-2 negative cohort A was at least as effective as T in term of overall survival.

CONCLUSIONS

These results suggest that in HER-2 positive breast cancer patients docetaxel might be more active than doxorubicin, while in HER-2 negative patients doxorubicin might be at least as effective as docetaxel. Although the present results cannot have an impact on current practice, they allow us to formulate the hypothesis that HER-2 positive breast cancer is a heterogeneous disease with regard to sensitivity to anthracyclines and taxanes, and that this might be dependent upon other molecular markers including the p-53 and topoisomerase II alpha genes. This hypothesis is currently being tested prospectively in two different 'bench to bed-side' clinical trials.

HER2 expression in breast cancer primary tumours and corresponding metastases. Original data and literature review

The aim of this study was to evaluate whether the HER2 expression in breast cancer is retained in metastases. The HER2 expression in primary tumours and the corresponding lymph node metastases were evaluated in parallel samples from 47 patients. The HercepTest was used for immunohistochemical analyses of HER2 overexpression in all cases. CISH/FISH was used for analysis of gene amplification in some cases. HER2 overexpression (HER2-scores 2+ or 3+) was found in 55% of both the primary tumours and of the lymph node metastases. There were only small changes in the HER2-scores; six from 1+ to 0 and one from 3+ to 2+ when the metastases were compared to the corresponding primary tumours. However, there were no cases with drastic changes in HER2 expression between the primary tumours and the corresponding lymph node metastases. The literature was reviewed for similar investigations, and it is concluded that breast cancer lymph node metastases generally overexpress HER2 to the same extent as the corresponding primary tumours. This also seems to be the case when distant metastases are considered. It has been noted that not all patients with HER2 overexpression respond to HER2-targeted Trastuzumab treatment. The stability in HER2 expression is encouraging for efforts to develop complementary forms of therapy, for example, therapy with radionuclide-labelled Trastuzumab.

HER-2 gene amplification can be acquired as breast cancer progresses

Amplification and overexpression of the HER-2 oncogene in breast cancer is felt to be stable over the course of disease and concordant between primary tumor and metastases. Therefore, patients with HER-2-negative primary tumors rarely will receive anti-Her-2 antibody (trastuzumab, Herceptin) therapy. A very sensitive blood test was used to capture circulating tumor cells (CTCs) and evaluate their HER-2 gene status by fluorescence in situ hybridization. The HER-2 status of the primary tumor and corresponding CTCs in 31 patients showed 97% agreement, with no false positives. In 10 patients with HER-2-positive tumors, the HER-2/chromosome enumerator probe 17 ratio in each tumor was about twice that of the corresponding CTCs (mean 6.64 +/- 2.72 vs. 2.8 +/- 0.6). Hence, the ratio of the CTCs is a reliable surrogate marker for the expected high ratio in the primary tumor. Her-2 protein expression of 10 CTCs was sufficient to make a definitive diagnosis of the HER-2 gene status of the whole population of CTCs in 19 patients with recurrent breast cancer. Nine of 24 breast cancer patients whose primary tumor was HER-2-negative each acquired HER-2 gene amplification in their CTCs during cancer progression, i.e., 37.5% (95% confidence interval of 18.8-59.4%). Four of the 9 patients were treated with Herceptin-containing therapy. One had a complete response and 2 had a partial response.

Monitoring the Circulating Levels of the HER2/neu Oncoprotein in Breast Cancer

The HER2/neu oncoprotein is a major target for the development of new cancer therapies and is similar to the estrogen receptor, which guides hormone therapy. The HER2/neu status is used to guide therapy decisions in patients with HER2/neu-overexpressing breast cancer tumors. The HER2/neu oncogene, or c-erbB-2, encodes a transmembrane receptor protein that is expressed on normal epithelial cells and can be overexpressed in breast cancer cells. Studies have shown that the extracellular domain (ECD) of the HER2/neu oncoprotein is released from the cell and can be measured in the circulation of women with breast cancer. Enzyme-linked immunosorbent assay methods used to measure the circulating HER2/neu ECD have shown that the prevalence of elevated ECD levels is approximately 18.1% in women with primary breast cancer and approximately 45.6% in women with metastatic breast cancer (MBC). Many studies have monitored the circulating ECD levels after surgery and indicate that increasing ECD levels can indicate recurrence of breast cancer earlier than clinical diagnosis. Studies in women with MBC showed that serial changes in circulating HER2/neu ECD levels paralleled the clinical course of disease, regardless of the treatment regimen. Several studies identified a subgroup of patients with MBC who had HER2/neu-negative disease by tissue testing but developed elevated ECD levels with MBC. In contrast to tissue testing, which is a one-time event, monitoring the circulating levels of the HER2/neu ECD in patients with breast cancer provides a real-time assessment of the HER2/neu status and provides important information for managing the therapy of patients with MBC.

Rates of topoisomerase II-alpha and HER-2 gene amplification and expression in epithelial ovarian carcinoma

OBJECTIVES

Topoisomerase II-alpha (T2a) is being actively investigated as a potential predictive marker of response to anthracyclines in breast cancer (BC). Although the role of T2a inhibitors as upfront and salvage treatment for epithelial ovarian carcinoma (EOC) remains unclear, we speculated that a small subgroup of ovarian cancer patients could derive a selective benefit from these agents. In this study, we investigated the actual rates of T2a and HER-2 amplification and overexpression by fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC), respectively.

METHODS

Seventy-three samples of chemotherapy-naive patients with EOC were selected from our archives. FIGO stage and histology were available for most patients.

RESULTS

Based on arbitrary cut-offs of > or =1.5 and > or =2 (ratio copies/centromere17), amplification rates for HER-2 were 15/64 (23.4%) and 8/64 (12.5%) versus 16/64 (25%) and 5/64 (7.8%) for T2a. We found only 3/72 (4.2%) cases of HER-2 overexpression (3+) versus 15/70 (21.4%) for T2a (staining of >10% of the cells). There was a modest correlation between T2a amplification and overexpression (P=0.01) and a strong correlation between T2a and HER-2 amplification when these markers were analysed as continuous variables (P<0.001). T2a amplification significantly correlated with advanced FIGO stage (P=0.02).

CONCLUSION

The assessment of HER-2 and T2a amplification and overexpression by FISH and IHC, respectively, is feasible in EOC. These tests can be used for large-scale evaluation of the potential predictive and prognostic value of these markers in the future. Further studies with a special focus on T2a are needed to determine the best cut-offs for potential clinical use in the future.

Change of HER-2/neu status in a subset of distant metastases from breast carcinomas

It is assumed that HER-2/neu status remains consistent in breast carcinoma during metastatic spread, but in most previous studies primary tumours were compared with concurrent regional lymph node metastases. The present study investigated 31 breast carcinomas and their corresponding lymph node and distant metastases for HER-2/neu status by immunohistochemistry (HercepTest) and fluorescence in situ hybridization (FISH) (PathVysion). In 14 cases, serum HER-2/neu (SHER-2) was measured sequentially using the Bayer Immuno 1 HER-2/neu assay. Comparing HER-2/neu immunohistochemistry of primary tumours and distant metastases case by case, increased HER-2/neu expression was found in the distant metastases in 15 cases (48.4%), three (9.7%) of which showed an increase from score 0 to score 3+. In contrast, lymph node metastases showed the same HER-2/neu expression as the primary tumours, confirmed by FISH. Two cases, which showed HER-2/neu score 3+ and HER-2/neu amplification in the primary tumours, revealed increased SHER-2 levels above 50 ng/ml at the first measurement. Five of the 14 cases (36%) showed an increase of SHER-2 above 50 ng/ml towards the end of the patients' life. On the basis of these results, there is evidence that in a subset of breast carcinomas, HER-2/neu amplification and overexpression occur de novo in distant metastases at a late disease stage.

HER-2/neu amplification by fluorescence in situ hybridization in cytologic samples from distant metastatic sites of breast carcinoma

BACKGROUND

Amplification of the HER-2/neu oncogene has been proposed as a target for antibody-based therapies and as a predictor of chemoresponsiveness in advanced breast carcinoma. Few studies have concentrated on HER-2/neu gene evaluation by fluorescence in situ hybridization (FISH) on distant metastatic sites and none have been performed on cytologic samples. The current study evaluated HER-2/neu amplification by FISH on cytologic samples obtained from distant metastatic lesions of breast carcinoma to update HER-2/neu characterization through a safe and easier procedure than biopsy.

METHODS

Twenty-two cytologic samples from distant metastases (12 hepatic samples, 4 skin samples, 3 pleural samples, and 3 peritoneal samples) were submitted to HER-2/neu evaluation by FISH. Seventeen corresponding primary breast tumors also were evaluated by FISH on paraffin histologic sections or on destained archival cytologic smears.

RESULTS

Seven of the 22 metastases (32%) were amplified. Amplification was observed in 4 of the 12 liver metastases, in 1of the 3 ascitic fluid specimens, and in 2 of the 4 skin metastases. In all the three pleural fluid specimens, HER-2/neu was unamplified. Matched results from primary and metastatic lesions were obtained in 14 cases (5 were amplified and 9 were unamplified on both primary and metastatic tumors).

CONCLUSIONS

The results of the current study emphasized the feasibility and advantages of two rapid and very informative techniques, such as fine-needle aspiration biopsy and FISH. Both procedures were performed to ascertain the malignant nature of a suspicious lesion and to obtain predictive markers for response. Since the advent of trastuzumab, the characterization of the molecular profile in metastatic breast disease has become increasingly important for targeted therapy selection.

Potential clinical utility of serum HER-2/neu oncoprotein concentrations in patients with breast cancer

BACKGROUND

The HER-2/neu oncogene and its p185 receptor protein are indicators of a more aggressive form of breast cancer. HER-2/neu status guides Herceptin therapy, specifically directed to the extracellular domain (ECD) of the HER-2/neu oncoprotein. The HER-2/neu ECD is shed from cancer cells into the circulation and is measurable by immunoassay.

METHODS

We performed a systematic review of the peer-reviewed literature on circulating ECD with respect to prevalence, prognosis, prediction of response to therapy, and monitoring of breast cancer.

RESULTS

The prevalence of increased ECD in patients with primary breast cancer varied between 0% and 38% (mean, 18.5%), whereas in metastatic disease the range was from 23% to 80% (mean, 43%). Some women with HER-2/neu-negative tumors by tissue testing develop increased ECD concentrations in metastatic disease. Increased ECD has been correlated with indicators of poor prognosis, e.g., overall survival and disease-free survival. Increased ECD predicts a poor response to hormone therapy and some chemotherapy regimens but can predict improved response to combinations of Herceptin and chemotherapy. Many studies support the value of monitoring ECD during breast cancer progression because serial increases precede the appearance of metastases and longitudinal ECD changes parallel the clinical course of disease.

CONCLUSIONS

The monitoring of circulating HER-2/neu ECD provides a tool for assessing prognosis, for predicting response to therapy, and for earlier detection of disease progression and timely intervention with appropriate therapy.

Her-2/neu status in breast cancer metastases to the central nervous system

CONTEXT

Breast cancer is lethal when it metastasizes; one frequent site for spread is the central nervous system (CNS). Approximately 15% to 30% of breast cancers overexpress the protein HER-2/neu at the primary site, but there are few data on whether metastases from these tumors overexpress HER-2/neu and might be responsive to the potentially toxic anti-HER-2/neu immunotherapy (trastuzumab [Herceptin]) used in patients with disseminated disease.

OBJECTIVE

To assess CNS breast cancer metastases for HER-2/neu protein overexpression by immunohistochemistry and gene amplification by fluorescence in situ hybridization (FISH) and to compare the status in primary and metastatic sites in the same patient, whenever possible.

DESIGN

Central nervous system breast cancer metastases (n = 53) from 33 patients and corresponding primary breast cancer specimens in a subset of these patients (n = 12) were retrospectively identified in surgical pathology and autopsy databases. Fluorescence in situ hybridization analysis using PathVysion probes for HER-2/neu and chromosome enumeration probe 17 (CEP 17) and immunohistochemistry using the c-Erb-B2 antibody (Dako A0485) were compared. Immunohistochemical sections were evaluated by both visual and image analysis techniques.

RESULTS

Of 31 cases assessable by FISH, 26% showed gene amplification. One hundred percent concordance for HER-2/neu status was detected between the primary and CNS metastatic lesions in 10 of 10 patients analyzed by FISH; lesser concordance was noted in 12 cases compared by immunohistochemistry. In 9 patients with multiple CNS metastases, FISH showed concordance among different lesions within the same patient.

CONCLUSIONS

When FISH is the detection method, CNS metastases accurately reflect the HER-2/neu status of the primary tumor. Central nervous system metastases from breast cancer received as surgical specimens can therefore be used to assess HER-2/neu status in patients in whom the primary tumor is unavailable for analysis.

Comparison of topoisomerase-IIalpha gene status between primary breast cancer and corresponding distant metastatic sites

BACKGROUND

Topoisomerase-IIalpha (topo-IIalpha) is a key enzyme in DNA replication and a molecular target for anticancer drugs called topoisomerase-II inhibitors, such as anthracyclines. Its value as a predictive marker of responsiveness to these cytotoxic drugs is currently being evaluated with promising results. However, even in the metastatic setting, the choice of treatment is based on the biologic characteristics of the primary tumor. Few data are available regarding the expression of biological markers between the primary tumor and the corresponding distant metastases.

METHODS

Topo-IIalpha gene status was evaluated in 29 breast cancer patients in which a primary tumor sample and a corresponding metastatic sample were both available. Fluorescent in situ hybridization (FISH) with the Vysis triple probe (Vysis multi-color topo-IIalpha spectrum orange, Her-2 spectrum green and CEP17 spectrum aqua probe) was used, which allowed the concomitant evaluation of HER-2 gene status.

RESULTS

As previously reported, topo-IIalpha gene aberrations are always associated with HER-2 gene amplification; indeed no topo-IIalpha gene aberrations have been observed in the HER-2 negative tumors. Conversely, 38.5% (five patients) of the HER-2 positive primary breast tumors (13 patients) were topo-IIalpha amplified, while 61.5% (eight patients) had a normal topo-IIalpha gene. No topo-IIalpha gene deletion was found in our series. Topo-IIalpha gene amplification in the primary tumor was always associated with amplification in the corresponding metastases, and no metastases with topo-IIalpha gene amplification were seen without amplification in the primary tumor. Furthermore, the amplification level of topo-IIalpha (i.e., ratio topo-IIalpha:CEP17) remained unchanged in primary and metastatic sites.

CONCLUSION

Despite the low number of patients, our results seem to indicate that topo-IIalpha gene status evaluation in the primary breast tumor accurately reflects its status in the corresponding distant metastases.