Comparative value of tumour grade, hormonal receptors, Ki-67, HER-2 and topoisomerase II alpha status as predictive markers in breast cancer patients treated with neoadjuvant anthracycline-based chemotherapy

Predictive value of pathological and immunohistochemical parameters for axillary lymph node metastasis in breast carcinoma

Background/Objective

While several prognostic factors have been identified in breast carcinoma, the clinical outcome remains hard to predict for individual patients. Better predictive markers are needed to help guide difficult treatment decisions. Axillary lymph node metastasis (ALNM) is one of the most important prognostic determinants in breast carcinoma; however, the reasons why tumors vary in their capability to result in axillary metastasis remain unclear. Identifying breast carcinoma patients at risk for ALNM would improve treatment planning. This study aimed to identify the factors associated with ALNM in breast carcinoma, with particular emphasis on basal-like phenotype.

Methods

Breast carcinoma patients (n = 210) who underwent breast conserving surgery and axillary lymph node dissection (ALND) (level I and II) or modified radical mastectomy were included in this study. Pathological and immunohistochemical data including individual receptor/gene status was collected for analysis. The basal phenotype status was ascertained using the basal cytokeratin markers CK5, CK14, CK17 and EGFR.

Results

ALNM was found in 55% (n = 116) of the patients. On univariate analysis, multicentric disease, large tumor size (>2 cm), vascular and lymphatic invasion, epithelial hyperplasia, necrosis, in situ carcinoma and perineural invasion were associated with higher risk for ALNM, whereas CK5, CK14, EGFR positivity and basal-like tumor type were associated with lower risk. On multivariate analysis, CK5 positivity (OR 0.003, 95%CI 0.000-0.23, p = 0.009) and lymphatic/vascular invasion (OR 17.94, 95%CI 4.78-67.30, p < 0.001) were found to be independent predictors.

Conclusions

Although the value of complete ALND has been questioned in invasive breast cancer patients, treatment decisions for breast carcinoma have been influenced by many parameters, including lymph node status. Since histopathologic characteristics and expression of biological markers varies among the same histologic subtypes of breast carcinoma, specific clinical and histopathologic features of the primary tumor and ALN status like sentinel node might be used to tailor the loco-regional and systemic treatment in different clinical settings.

Clinical significance of Ki-67 in neoadjuvant chemotherapy for primary breast cancer as a predictor for chemosensitivity and for prognosis

BACKGROUND

Neoadjuvant chemotherapy (NAC) is one of the main strategies for patients with locally advanced breast cancer. In recent years several biological markers such as estrogen receptor (ER), progesterone receptor (PgR), and HER2 were discovered to be predictive factors for the effectiveness of NAC to help individualize treatment. In this retrospective study, we focused on Ki-67 as a biological marker and examined the correlation between Ki-67 and chemosensitivity, and the prognosis after the start of treatment.

PATIENTS AND METHODS

Between July 1996 and March 2008, 148 patients with tumors ≥ 3 cm in diameter or lymph node metastases received NAC and surgery. The items investigated were ER/PgR and Ki-67 from core needle biopsy. The treatment regimens were EC in 36 cases, ET in 51 cases, and FEC-DOC in 61 cases. The patients with FEC-DOC regimen had smaller tumors and higher Ki-67 values than the others.

RESULTS

Clinical response (cCR + cPR) was 79.7%, and the pathological complete response (pCR) was 14.2%. Multivariate analysis revealed that Ki-67 was significantly related to pCR. Moreover, there was no pathological responder in cases with Ki-67 < 25%. The Ki-67 values significantly decreased after NAC (median from 45.0 to 17.5%). Patients with cCR had significantly lower Ki-67 values after NAC than those with cPR, cSD, and cPD. There was a significant difference in the Ki-67 value in terms of the presence and the absence of recurrence (median 26.0% with recurrence vs. 12% without recurrence). The disease-free survival (DFS) rate after the start of treatment was significantly higher in the patients with Ki-67 < 12% after NAC than those with Ki-67 ≥ 12%.

CONCLUSION

The Ki-67 value before NAC was a significant predictive factor for the effectiveness of NAC. The Ki-67 values after NAC significantly decreased and correlated with clinical response and DFS. Therefore, higher Ki-67 values (≥ 25%) before NAC as well as lower values (<12%) after NAC might be clinically significant for treating patients.

Ki-67 can be used for further classification of triple negative breast cancer into two subtypes with different response and prognosis

INTRODUCTION

Triple negative breast cancer (TNBC) has a poorer survival, despite a higher response rate to neoadjuvant chemotherapy. The purpose of this study was to identify the predictive or prognostic value of Ki-67 among patients with TNBC treated with neoadjuvant chemotherapy, and the role of Ki-67 in further classification of TNBC.

METHODS

A total of 105 TNBC patients who received neoadjuvant docetaxel/doxorubicin chemotherapy were included in the present study. Pathologic complete response (pCR) rate, relapse-free survival (RFS), and overall survival (OS) were compared according to the level of Ki-67.

RESULTS

pCR was observed in 13.3% of patients. TNBC with high Ki-67 expression (≥ 10%) showed a higher pCR rate to neoadjuvant chemotherapy than TNBC with low Ki-67 expression. None of the low Ki-67 group achieved pCR (18.2% in the high Ki-67 group vs. 0.0% in the low Ki-67 group, P = 0.019). However, a high Ki-67 expression was significantly associated with poor RFS and OS in TNBC, despite a higher pCR rate (P = 0.005, P = 0.019, respectively). In multivariate analysis, high Ki-67 was an independent prognostic factor for RFS in TNBC (hazard ratio = 7.82, P = 0.002). The high Ki-67 group showed a similar pattern of recurrence with overall TNBC, whereas the low Ki-67 group demonstrated a relatively constant hazard rate for relapse.

CONCLUSIONS

TNBC with high Ki-67 was associated with a more aggressive clinical feature despite a higher pCR rate. High proliferation index Ki-67 can be used for further classification of TNBC into two subtypes with different responses and prognosis.

[Predictive factors of response to anthracyclines neoadjuvant chemotherapy in breast cancer]

OBJECTIVES

Anthracyclines chemotherapy remains primordial and impossible to circumvent in the treatment of breast cancer, in the adjuvant, metastatic and neoadjuvant setting. But some breast invasive tumors are resistant to anthracyclines. The neoadjuvant model is ideal to test the chemosensibility by selecting the well-responder patients and identifying the predictive factors of this response.

PATIENTS AND METHODS

We report a retrospective study of 126 patients treated at our institute during 2 years (January 2003-December 2004) for a breast cancer with primary chemotherapy. All the patients received anthracyclines according to protocol AC60 (doxorubicine plus cyclophosphamide).

RESULTS

The clinical objective response rate (RO) was 67 % with a complete clinical response (RC) of 11 %. We found a pathological complete response (pCR) in seven patients (5,6 %) of the 126 cases. The statistical study identifies only two clinical factors as predictive of RC and pCR: tumoral size T2-T3 and clinical nodal status N0-N1, while the SBR grading and the hormonal receptors were not correlated.

DISCUSSION AND CONCLUSION

Some clinical and histological factors are recognized as predictive for the benefit of anthracyclines neoadjuvant chemotherapy, and correlated to the pCR; we discuss our results through those of the literature, by exposing the current data.

Immunomarker studies of fine-needle cytopuncture cell blocks for tumor response prediction after preoperative chemotherapy and prognosis in operable nonmetastatic primary breast carcinoma

Neo-adjuvant chemotherapy of breast cancer provides an opportunity to evaluate predictive factors at initial tumor biopsy. We evaluated these factors on cell blocks obtained by diagnostic fine-needle cytopuncture (FNC), with respect to tumor regression and outcome. A prospective study (1996-2003, median follow-up 82 months) involved 163 patients with breast carcinoma (T2 ≥ 3 cm, T3, T4 noninflammatory) diagnosed by means of FNC. Malignancy, cytologic grade, and the presence of lymphocytes were determined on cytologic smears. Ki67, estrogen receptor (ER), progesterone receptor (PgR), HER2, and p53 expression was assessed on cell blocks by means of immunohistochemistry. All the patients received anthracycline-based chemotherapy. A combined clinical and pathologic tumor regression score was calculated. Twelve cases (7.5%) showed a complete regression, 72 cases (44%) a partial regression and 79 cases (48.5%) no regression. Factors predictive of regression were high grade, presence of lymphocytes, pN0, high Ki67 expression, hormone receptor negativity, and the "triple negative" phenotype. In univariate analysis 5-year metastasis-free survival rate (MFS) correlated with cytologic grade, pN, ER, and p53 status, while overall survival (OS) correlated with cytologic grade, type of surgery, pN, and ER status. In multivariate analysis, MFS was significantly influenced by the regression score, Ki67, age, ER status, pN, HER2, and initial tumor size. Except for age, the same parameters correlated with OS. FNC with the cell block technique is a rapid, minimally invasive, reliable, and inexpensive method for analyzing predictive biomarkers, and may thus be useful in the management of breast cancer patients requiring neo-adjuvant chemotherapy.

Hormone receptor status rather than HER2 status is significantly associated with increased Ki-67 and p53 expression in triple-negative breast carcinomas, and high expression of Ki-67 but not p53 is significantly associated with axillary nodal metastasis in triple-negative and high-grade non-triple-negative breast carcinomas

Triple-negative (TN) breast carcinoma is associated with a higher recurrence rate and shorter survival and lacks the benefit of specific therapy. TN tumors usually express high levels of Ki-67 and p53 that are considered prognostic markers for breast cancer. We compared Ki-67 and p53 expression between TN and high-grade non-TN invasive carcinomas in a total of 214 cases and investigated an association between their expression and axillary nodal metastasis in these tumors. Our findings demonstrate that TN tumors are associated with significantly higher expression of Ki-67 and p53 compared with non-TN tumors, which may contribute to the poorer prognosis in TN tumors. Hormone receptor negativity rather than HER2 negativity is associated with the significantly increased Ki-67 and p53 expression in TN tumors. Furthermore, a high expression level of Ki-67 but not p53 is more likely to be associated with axillary nodal metastasis in these cases.

ER, PgR, HER-2, Ki-67, topoisomerase IIα, and nm23-H1 proteins expression as predictors of pathological complete response to neoadjuvant chemotherapy for locally advanced breast cancer

The purpose of this study was to evaluate the importance of biological markers to predict pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) in patients with locally advanced breast cancer (LABC) One hundred and twelve consecutive patients with clinical stage III LABC who had received NCT with docetaxel and epirubicin from March 2006 to March 2009 were included in this retrospective study. The pre-NCT treatment expression levels of Ki-67 proliferation index, estrogen receptor (ER), progesterone receptor (PgR), epidermal growth factor receptor 2 (HER-2), Topoisomerase II alpha (Topo-II), and nm23-H1 were detected by immunohistochemistry (IHC). A total of 361 cycles were administered with the median number of three cycles per patient (range, 2-6). The pCR rate was 9.8% (95% CI, 4.3-15.3%). In univariate analysis, poor tumor differentiation, both negative of ER/PgR, negative Topo-II, and positive nm23-H1 were found to be significantly predictive of a pCR. ER/PgR status and nm23-H1 were significant for pCR on multivariate analysis (P = 0.006 and 0.025, respectively). ER/PgR status and nm23-H1 are independent predictive factors of pCR to neoadjuvant docetaxel plus epirubicin combination chemotherapy in patients with LABC.

Semi-quantitative evaluation of estrogen receptor expression is a strong predictive factor of pathological complete response after anthracycline-based neo-adjuvant chemotherapy in hormonal-sensitive breast cancer

Absence of hormonal receptors (HR) expression is a predictive factor of high pathologic complete response (pCR) rate after neo-adjuvant chemotherapy. However, HR-positive tumors are less chemosensitive. In the present study, we evaluated the predictive value of estrogen (ER) and progesterone (PgR) semi-quantitative expression in patients with HR-positive tumors treated uniformly with antracycline-based neoadjuvant chemotherapy without hormonal treatment. Value of HR expression as a predictive factor was then evaluated in a multivariate analysis with tumor grade, Ki67 index and HER2 expression. From January 2000 and December 2006, 177 patients with HR-positive breast ductal invasive carcinoma ≥2 cm in its largest diameter were treated with six cycles of an anthracycline-based neo-adjuvant chemotherapy. Tumor grade, ER, PgR, HER2 status and Ki67 index were determined on microbiopsy performed before chemotherapy. A semi-quantitative evaluation of ER and PgR expression by IHC was performed using the Barnes'score. pCR rate was significantly different (P < 0.001) according to the ER expression score. pCR rate was 28% for low score, 9% for medium score and 3% for high score. On the contrary, pCR rate was not significantly different (P = 0.49) according to the PgR expression score. In the multivariate analysis, ER expression score (P = 0.0002) and Ki67 index (P = 0.02) were the only predictive factors of response for HR-positive tumors. pCR after anthracycline-based chemotherapy is significantly correlated with the ER expression score.

Molecular alterations in key-regulator genes among patients with T4 breast carcinoma

Background

Prognostic factors in patients who are diagnosed with T4 breast carcinomas are widely awaited. We here evaluated the clinical role of some molecular alterations involved in tumorigenesis in a well-characterized cohort of T4 breast cancer patients with a long follow-up period.

Methods

A consecutive series of 53 patients with T4 breast carcinoma was enrolled between 1992 and 2001 in Sardinia, and observed up for a median of 125 months. Archival paraffin-embedded tissue sections were used for immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) analyses, in order to assess alterations in expression levels of survivin, p53, and pERK_1-2 proteins as well as in amplification of CyclinD1 and h-prune genes. The Kaplan-Meier and Cox regression methods were used for survival assessment and statistical analysis.

Results

Overall, patients carrying increased expression of pERK_1-2 (p = 0.027) and survivin (p = 0.008) proteins as well as amplification of h-prune gene (p = 0.045) presented a statistically-significant poorer overall survival in comparison with cases found negative for such alterations. After multivariate analysis, the pathological response to primary chemotherapy and the survivin overexpression in primary carcinoma represented the main parameters with a role as independent prognostic factors in our series.

Conclusions

Although retrospective, our study identified some molecular parameters with a significant impact on prediction of the response to therapy or prognosis among T4 breast cancer patients. Further large prospective studies are needed in order to validate the use of such markers for the management of these patients.

Topoisomerase II-α as a predictive factor of response to therapy with anthracyclines in locally advanced breast cancer

BACKGROUND

Topoisomerase II-α is a molecular target of anthracyclines; several studies have suggested that topoisomerase II-α expression is related to response to anthracycline treatment. The objective of this study was to evaluate if topoisomerase II-α overexpression predicts response to anthracycline treatment in locally advanced breast cancer patients.

MATERIAL AND METHODS

Topoisomerase II-α, HER2, estrogen receptor (ER) and progesterone receptor (PR) expression were evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded breast tumors from 111 patients presenting with locally advanced breast cancer between 1995 and 2002. The prognostic value of these markers was analyzed using a multivariate proportional hazards regression model and an interaction analysis between topoisomerase II-α status and dose intensity.

RESULTS

Tumors from 40 patients (36%) showed topoisomerase II-α overexpression, 62 patients (56%) for ER, 39 (35%) for PR and 26 (23%) for HER2. There were no significant correlations between topoisomerase II-α expression and response to therapy, progression-free survival (PFS) or overall survival (OS). Anthracycline dose intensity had a significant impact on PFS and OS in patients overexpressing topoisomerase II-α (P=0.010 and 0.027, respectively). Negative PR (P=0.041), positive HER2 (P=0.013) were identified as risk factors in the multivariate model. The multivariate analysis in patients topoisomerase II-α negative shown no significance (HR=0.92, IC 95% 0.39-2.15, P=0.839) while the multivariate analysis in topoisomerase II-α positive, dose intensity shown to be statistically significant (HR=2.725, IC 95% 1.07-6.95, P=0.036).

CONCLUSIONS

Our data do not support a correlation between topoisomerase II-α expression in breast cancer patients and improved clinical benefit with anthracycline therapy. However, they do suggest that tumors overexpressing topoisomerase II-α may experience better clinical benefit with higher anthracycline dose intensity.

Ki-67 as a prognostic marker according to breast cancer subtype and a predictor of recurrence time in primary breast cancer

The choice of adjuvant systemic therapy is based on targeted therapy in line with the St. Gallen Consensus meeting. In addition to the traditional parameters, the panel recommended the use of proliferation markers and multigene assays. The purpose of the present study was to evaluate the clinical significance of proliferative activity using the Ki-67 index as a prognostic marker and as a predictor of recurrence time in breast cancer patients. The Ki-67 index was measured in 3,652 cases with primary breast cancer from 1987 to 2009. Out of these patients, 2,638 cases were evaluated simultaneously for estrogen receptor, progesterone receptor and HER2 from 1997, and these were analyzed as a prognostic factor according to their subtypes. The Ki-67 index exhibited a wide range of 1-99%, with a median of 20%, and cases were divided into 2 or 3 index groups; <20% and ≥20% (and ≥50%). The median Ki-67 index of tumors with luminal A was 17%, and that of luminal B type tumors was 29%. The Ki-67 index of HER2 tumors was 40% and that of triple negative tumors was 50%. A higher Ki-67 index significantly correlated with a higher grade of malignancy. Patients with a higher Ki-67 index had significantly lower disease-free survival (DFS) and overall survival rates. Moreover, there was a significant difference in the recurrence time. Multivariate analysis revealed that the Ki-67 index was a significant factor for DFS, irrespective of nodal status, and that Ki-67 was a significant marker only in luminal A type tumors. Furthermore, luminal A type cases with high Ki-67 had a similar DFS as the luminal B type cases. A higher Ki-67 index (≥20%) significantly correlated with other biological markers, poorer prognosis and early recurrence, particularly in luminal A type tumors. It is important to take the Ki-67 index into consideration in the treatment and follow-up of breast cancer patients.

Immunohistochemical assessment of primary breast tumors and metachronous brain metastases, with particular regard to differences in the expression of biological markers and prognosis

In this study, we conducted an immunohistochemical analysis of primary breast tumors and metachronous brain metastases to compare the differences in the expression of biological markers between the two. Carcinoma tissues from primary breast tumors and metachronous brain metastases collected from 21 patients were examined immunohistochemically for the expression status of the estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor (HER)-2, Ki-67, bcl-2 and p53, and the results were compared. In addition, the relationships between the expression of these factors and prognosis were evaluated. There were no significant differences in the frequencies of ER-, PgR-, HER-2-, bcl-2- or p53-positivity between the primary breast tumors and metachronous brain metastases. While the Ki-67 labeling index (LI) was high in both the primary breast tumors and brain metastases, it was significantly higher in the brain metastases than in the corresponding primary breast tumors (P=0.003). With regard to the prognosis, breast cancer patients who showed ER-positivity in the primary tumors showed significantly longer survival after primary diagnosis (P=0.0076). Furthermore, breast cancer patients who exhibited ER-positivity, bcl-2-positivity or p53-negativity in the primary tumors showed significantly longer intervals from primary diagnosis to the detection of the brain metastases. Of all the markers, only the Ki-67 LI was significantly higher in the brain metastases than in the primary breast tumors. We confirmed that the tumor characteristics were worse in the metachronous brain metastases.

Evaluation of Ki-67 and Bcl-2 antigen expression in breast carcinomas of women treated with raloxifene

OBJECTIVES

To evaluate the effect of raloxifene on Ki-67 and Bcl-2 antigen expression in operable, stage II, oestrogen-receptor-positive invasive ductal breast carcinomas.

MATERIALS AND METHODS

Twenty post-menopausal women who had taken 60 mg of raloxifene daily for 28 days prior to definitive surgery were enrolled in the investigation. Two tumour samples were obtained by incisional biopsy during the study, one at the time of confirmation of diagnosis of invasive ductal carcinoma and evaluation of oestrogen receptor status, and the other 29 days later, at the time of definitive surgery. Immunohistochemistry was performed on tumour samples, prior to and after raloxifene treatment, to evaluate Ki-67 and Bcl-2 expression. Friedman and McNemar tests were used for statistical analysis of the data, significance being established at 5%.

RESULTS

Mean percentage of Ki-67-stained nuclei was 24.86 +/- 2.95 prior to raloxifene treatment and 13.33 +/- 1.52 after treatment (P < 0.001). Prior to raloxifene treatment, only 9/20 cases (45%) were classified as Bcl-2-positive, whereas after treatment, 17/20 (85%) were classified as Bcl-2-positive (P < 0.013).

CONCLUSIONS

Raloxifene treatment significantly reduced Ki-67 antigen expression and increased Bcl-2 expression in breast carcinomas of post-menopausal women.

CDO1 promoter methylation is a biomarker for outcome prediction of anthracycline treated, estrogen receptor-positive, lymph node-positive breast cancer patients

Background

Various biomarkers for prediction of distant metastasis in lymph-node negative breast cancer have been described; however, predictive biomarkers for patients with lymph-node positive (LNP) disease in the context of distinct systemic therapies are still very much needed. DNA methylation is aberrant in breast cancer and is likely to play a major role in disease progression. In this study, the DNA methylation status of 202 candidate loci was screened to identify those loci that may predict outcome in LNP/estrogen receptor-positive (ER+) breast cancer patients with adjuvant anthracycline-based chemotherapy.

Methods

Quantitative bisulfite sequencing was used to analyze DNA methylation biomarker candidates in a retrospective cohort of 162 LNP/ER+ breast cancer patients, who received adjuvant anthracycline-based chemotherapy. First, twelve breast cancer specimens were analyzed for all 202 candidate loci to exclude genes that showed no differential methylation. To identify genes that predict distant metastasis, the remaining loci were analyzed in 84 selected cases, including the 12 initial ones. Significant loci were analyzed in the remaining 78 independent cases. Metastasis-free survival analysis was conducted by using Cox regression, time-dependent ROC analysis, and the Kaplan-Meier method. Pairwise multivariate regression analysis was performed by linear Cox Proportional Hazard models, testing the association between methylation scores and clinical parameters with respect to metastasis-free survival.

Results

Of the 202 loci analysed, 37 showed some indication of differential DNA methylation among the initial 12 patient samples tested. Of those, 6 loci were associated with outcome in the initial cohort (n = 84, log rank test, p < 0.05).

Promoter DNA methylation of cysteine dioxygenase 1 (CDO1) was confirmed in univariate and in pairwise multivariate analysis adjusting for age at surgery, pathological T stage, progesterone receptor status, grade, and endocrine therapy as a strong and independent biomarker for outcome prediction in the independent validation set (log rank test p-value = 0.0010).

Conclusions

CDO1 methylation was shown to be a strong predictor for distant metastasis in retrospective cohorts of LNP/ER+ breast cancer patients, who had received adjuvant anthracycline-based chemotherapy.

Neoadjuvant chemotherapy of breast cancer: tumor markers as predictors of pathologic response, recurrence, and survival

This study reports the value of the tumor markers estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) in predicting the response of breast cancer to neoadjuvant chemotherapy. A community cancer center prospectively maintained breast cancer database containing over 8,000 patient records was used. Since 1989, 464 patients were treated with neoadjuvant chemotherapy followed by surgical resection and were tested for ER and PR. Estrogen receptor and/or PR positive patients were considered hormone receptor (HR) positive. Human epidermal growth factor receptor 2 status was available on 368 patients. Total, breast, and nodal pathologic complete response (pCR) rates, recurrence, and overall survival were assessed. Total and breast pCR rates were higher in HR negative (HR-) patients (26% and 32%, respectively) than in HR positive (HR+) patients (4% and 7%, respectively; p < 0.001). Compared to HR+ patients, HR- patients had higher recurrence rates (38% versus 22%; p < 0.001), a shorter time to recurrence (1.28 versus 2.14 years; p < 0.001), and decreased overall survival (67% versus 81%; p < 0.001). Human epidermal growth factor receptor 2 positive patients treated with neoadjuvant trastuzumab (NAT) demonstrated higher total pCR (34% versus 13%; p = 0.008), breast pCR (37% versus 17%; p = 0.02), and nodal pCR rates (47% versus 23%; p = 0.05) compared to HER2+ patients not treated with NAT. Furthermore, HER2+ patients who received NAT had lower recurrence rates (5% versus 42%; p < 0.001) and increased overall survival (97% versus 68%; p < 0.001). In conclusion, breast cancer HR status is predictive of total and breast pCR rates after neoadjuvant chemotherapy. Although HR- patients derive greater benefit from neoadjuvant chemotherapy in terms of pathologic response, they have worse outcomes in terms of recurrence and survival. Hormone receptor positive patients demonstrate significantly less response to neoadjuvant chemotherapy, but significantly better overall outcome. For both HR- and HR+, addition of NAT for HER2+ tumors results in both a superior response and outcome.

Ki67 in breast cancer: prognostic and predictive potential

The leading parameters that define treatment recommendations in early breast cancer are oestrogen-receptor, progesterone-receptor, and human epidermal growth-factor status. Although some pathologists report Ki67 in addition to other biological markers, the existing guidelines of the American Society of Clinical Oncology do not include Ki67 in the list of required routine biological markers. The advent of new genetic tests has emphasised the role of proliferative genes, including Ki67, as prognostic and predictive markers. Additionally, randomised studies have retrospectively reviewed data and reported on the role of Ki67 in breast cancer. In light of new data, we have re-assessed evidence that could change guidelines to include Ki67 in the standard pathological assessment of early breast cancers. This review provides an update on the current knowledge on Ki67 and of the evidence in the published work about the prognostic and predictive role of this marker, and provides information on the laboratory techniques used to determine Ki67.

Antiproliferative effect of peripheral benzodiazepine receptor antagonist PK11195 in rat mammary tumor cells

This study aims to establish the antiproliferative effects of PK11195, a peripheral benzodiazepine receptor antagonist (PBR) in rat mammary tumor cells. Breast tumors were induced by administration of a carcinogen, dimethylbenz[a]anthracene to 50-day-old female rats maintained on a standard AIN-76A diet with casein as the protein source. The tumors were developed approximately after 120 days. The tumors were of grade I (20%), grade II (60%), and grade III (20%). The tumors were isolated and cultured in DMEM/F12 media with supplements. We characterized the properties of the isolated cells and study the effect of PK11195 on those cells. We were successful in growing breast tumor cells up to 30 passages for cellular characterization. These cells had high reactivity with Ki-67 and PCNA antibodies suggesting high proliferation rate. These cells were highly invasive as evident by matrigel invading ability. Furthermore, these cells acquired a positive response for CD-31 and VEGF antibodies suggesting angiogenic potential, and also possessed migrating ability/motility as evident by the wound healing properties. These cells expressed elevated levels of PBR, a cancer promoting gene. The proliferation, invasion and migration appear to decrease when treated with PK11195, a PBR antagonist. Furthermore, PK11195 treatment caused an increase in apoptosis as evident by increase in the levels of annexin V. However, the inhibition of cell proliferation by PK11195 was counteracted by Ro5-4864, a PBR agonist. Thus, PBR antagonist may be a potential therapeutic agent for the control of aggressiveness of breast cancer.

Identification of biology-based breast cancer types with distinct predictive and prognostic features: role of steroid hormone and HER2 receptor expression in patients treated with neoadjuvant anthracycline/taxane-based chemotherapy

Introduction

Reliable predictive and prognostic markers for routine diagnostic purposes are needed for breast cancer patients treated with neoadjuvant chemotherapy. We evaluated protein biomarkers in a cohort of 116 participants of the GeparDuo study on anthracycline/taxane-based neoadjuvant chemotherapy for operable breast cancer to test for associations with pathological complete response (pCR) and disease-free survival (DFS). Particularly, we evaluated if interactions between hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) expression might lead to a different clinical behavior of HR+/HER2+ co-expressing and HR+/HER2- tumors and whether subgroups of triple negative tumors might be identified by the help of Ki67 labeling index, cytokeratin 5/6 (CK5/6), as well as cyclooxygenase-2 (COX-2), and Y-box binding protein 1 (YB-1) expression.

Methods

Expression analysis was performed using immunohistochemistry and silver-enhanced in situ hybridization on tissue microarrays (TMAs) of pretherapeutic core biopsies.

Results

pCR rates were significantly different between the biology-based tumor types (P = 0.044) with HR+/HER2+ and HR-/HER2- tumors having higher pCR rates than HR+/HER2- tumors. Ki67 labeling index, confirmed as significant predictor of pCR in the whole cohort (P = 0.001), identified HR-/HER- (triple negative) carcinomas with a higher chance for a pCR (P = 0.006). Biology-based tumor type (P = 0.046 for HR+/HER2+ vs. HR+/HER2-), Ki67 labeling index (P = 0.028), and treatment arm (P = 0.036) were independent predictors of pCR in a multivariate model. DFS was different in the biology-based tumor types (P < 0.0001) with HR+/HER2- and HR+/HER2+ tumors having the best prognosis and HR-/HER2+ tumors showing the worst outcome. Biology-based tumor type was an independent prognostic factor for DFS in multivariate analysis (P < 0.001).

Conclusions

Our data demonstrate that a biology-based breast cancer classification using estrogen receptor (ER), progesterone receptor (PgR), and HER2 bears independent predictive and prognostic potential. The HR+/HER2+ co-expressing carcinomas emerged as a group of tumors with a good response rate to neoadjuvant chemotherapy and a favorable prognosis. HR+/HER2- tumors had a good prognosis irrespective of a pCR, whereas patients with HR-/HER- and HR-/HER+ tumors, especially if they had not achieved a pCR, had an unfavorable prognosis and are in need of additional treatment options.

Trial registration

ClinicalTrials.gov identifier: NCT00793377

The topoisomerase II alpha gene status in primary breast cancer is a predictive marker of the response to anthracycline-based neoadjuvant chemotherapy

This study aimed at evaluating the usefulness of topoisomerase II alpha (TOP2A) for predicting the effect of anthracycline-based neoadjuvant chemotherapy in breast cancer. The TOP2A status was examined using fluorescent in situ hybridization (FISH) in 14 pre-chemotherapeutic breast cancer tissues, and was also assessed by immunohistochemistry (IHC) in 14 pairs of pre- and post-chemotherapeutic breast cancer specimens. TOP2A gene aberration by IHC tended to show a correlation with pathological responses but this was not statistically significant (p=0.060). On the other hand, the low TOP2A/CEP17 ratio correlated with good pathological responses (p=0.012). TOP2A overexpression was not significantly associated with response (p=0.580). Our results thus suggest that the TOP2A/CEP17 ratio may be a useful predictor of the effects of anthracycline-based neoadjuvant chemotherapy in breast cancer.

Simultaneous detection of TOP2A and HER2 gene amplification by multiplex ligation-dependent probe amplification in breast cancer

HER-2/neu gene amplification, found in certain subtypes of (breast-) cancers, is an independent prognostic factor of poor outcome and determines eligibility for systemic treatment with trastuzumab. TopoII alpha (TOP2A) gene amplification seems to be predictive of response to a class of cytostatic agents called TopoII inhibitors, which include the anthracyclines. The observed increased efficacy of anthracyclines in HER2-positive tumors is thought to arise from the close proximity of both genes on chromosome 17, where the TopoII amplification status will determine the anthracycline sensitivity. This study aimed to validate a new polymerase chain reaction-based test, called multiplex ligation-dependent probe amplification (MLPA), as a simple and quick method to simultaneously assess HER-2/neu and TopoII alpha gene amplification status in paraffin-embedded breast cancer samples. To this end, MLPA results were compared with TopoII alpha, HER2 chromogenic in situ hybridization (CISH). We also assessed TopoII alpha protein expression by immunohistochemistry. Of 353 patients, 9% showed TopoII alpha amplification by MLPA and 13% of patients were HER2 amplified. TopoII alpha amplification was seen in 42% of HER2-amplified cases and showed no high level amplification without HER2 amplification. Eleven patients displayed TopoI alpha loss (3%). Concordance between MLPA and CISH was 91% for TopoII alpha and 96% for HER2. Correlation between amplification and overexpression of TopoII alpha was significant (P=0.035), but amplification did not always predict protein overexpression. Loss of the TopoII alpha gene was almost never associated with loss of its protein. In conclusion, MLPA is an easy and accurate method to simultaneously detect breast cancer HER-2/neu and TopoII alpha copy number status in paraffin-embedded tissue, and thus an attractive supplement or alternative to CISH.

Progression and treatment of HER2-positive breast cancer

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Neoadjuvant endocrine treatment in primary breast cancer - review of literature

Chemotherapeutic agents have dominated neoadjuvant treatment compared to endocrine agents in the past and have demonstrated their ability to produce tumour shrinkage to allow breast conservation. However, in the more recent setting, studies have been emerging with the use of aromatase inhibitors, especially comparing its use with tamoxifen in selected group of patients. The role of tamoxifen in its ability to achieve tumour shrinkage has been evaluated in the past, and has shown to produce slow but sustained response. Aromatase inhibitors have shown superiority over tamoxifen in adjuvant and metastatic setting, and the aim of our study was to compare their outcome with regard to response and breast conservation in the neoadjuvant setting. We also looked into optimum duration of neoadjuvant treatment and also the role of pathological complete response as a surrogate marker for clinical outcome. Our review highlights the superiority of aromatase inhibitors over tamoxifen in the neoadjuvant setting and even challenges chemotherapy with regard to response in selected group of patients.

Predictive factors for anthracycline-based chemotherapy for human breast cancer

Predictive factors for anthracycline-based chemotherapy have yet to be incorporated into daily practice. Meta-analyses of studies using anthracycline-based treatment regimens have shown an improved prognosis for human epidermal growth factor receptor type 2 (HER2)-positive tumors, but not for HER2-negative tumors compared with results of non-anthracycline regimens. Currently it is believed that the positive association between HER2 status and anthracycline sensitivity is indirect, that is, their association may be mediated through topoisomerase II alpha (TOP2A), a target molecule of anthracyclines, since TOP2A is near HER-2 and co-amplification of the TOP2A gene frequently occurs in HER2-amplified tumors. This strongly suggests that TOP2A gene amplification is a predictive factor for anthracyline-based regimens. The Collaborative Study Group of Scientific Research of the Japanese Breast Cancer Society has demonstrated that TOP2A-positive and BRCA1-negative subsets evaluated by immunohistochemical staining show a significantly higher pathological complete response when treated with preoperative epirubicin-containing regimens. Combining these findings with the observation that triple-negative tumors and basal-like tumors respond to anthracycline treatment suggests that not only HER2-positive tumors but also a distinct subset of HER2-negative tumors may be sensitive to anthracycline-based regimens.

PAR1 is selectively over expressed in high grade breast cancer patients: a cohort study

Background

The protease-activated receptor (PAR1) expression is correlated with the degree of invasiveness in cell lines. Nevertheless it has never been directed involved in breast cancer patients progression. The aim of this study was to determine whether PAR1 expression could be used as predictor of metastases and mortality.

Methods

In a cohort of patients with infiltrating ductal carcinoma studied longitudinally since 1996 and until 2007, PAR1 over-expression was assessed by immunoblotting, immunohistochemistry, and flow citometry. Chi-square and log rank tests were used to determine whether there was a statistical association between PAR1 overexpression and metastases, mortality, and survival. Multivariate analysis was performed including HER1, stage, ER and nodes status to evaluate PAR1 as an independent prognostic factor.

Results

Follow up was 95 months (range: 2–130 months). We assayed PAR1 in a cohort of patients composed of 136 patients; we found PAR1 expression assayed by immunoblotting was selectively associated with high grade patients (50 cases of the study cohort; P = 0.001). Twenty-nine of 50 (58%) patients overexpressed PAR1, and 23 of these (46%) developed metastases. HER1, stage, ER and PAR1 overexpression were robustly correlated (Cox regression, P = 0.002, P = 0.024 and P = 0.002 respectively). Twenty-one of the 50 patients (42%) expressed both receptors (PAR1 and HER1 P = 0.0004). We also found a statistically significant correlation between PAR1 overexpression and increased mortality (P = 0.0001) and development of metastases (P = 0.0009).

Conclusion

Our data suggest PAR1 overexpression may be involved in the development of metastases in breast cancer patient and is associated with undifferentiated cellular progression of the tumor. Further studies are needed to understand PAR1 mechanism of action and in a near future assay its potential use as risk factor for metastasis development in high grade breast cancer patients.

Relationship between oestrogen receptor status and proliferation in predicting response and long-term outcome to neoadjuvant chemotherapy for breast cancer

Oestrogen receptor (ER) negative breast cancers are more likely to achieve a pathological complete response (pCR) to neoadjuvant chemotherapy compared to those with ER positive tumours. ER positive tumours exhibit low proliferation and ER negative cancers high proliferation. The aim of this study was to determine to what extent the better response of ER negative cancers correlates with proliferation rate. A retrospective analysis of a prospectively maintained database identified 175 neoadjuvant chemotherapy patients with tissue available for Ki67 analysis. On univariate analysis, pre-therapy Ki67 (P = 0.04), ER status (P = 0.002), HER2 status (P = 0.004) and grade (P = 0.0009) were associated with a pCR. In a multivariate model, HER2 was the only significant predictor of pCR. No significant relationship between pre-therapy Ki67 and relapse-free and overall survival was demonstrated. Ki67 is not an independent predictor of clinical CR or pCR. Aspects of ER status beyond its inverse relationship with proliferation may contribute to its predictive value for pCR.

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

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

Topoisomerase II alpha gene copy loss has adverse prognostic significance in ERBB2-amplified breast cancer: a retrospective study of paraffin-embedded tumor specimens and medical charts

BACKGROUND

Amplification of the ERBB2 (Her-2/neu) oncogene, which occurs in approximately 25% of breast carcinomas, is a known negative prognostic factor. Available data indicate that a variable number of nearby genes on chromosome 17q may be co-amplified or deleted, forming a continuous amplicon of variable size. In approximately 25% of these patients, the amplicon extends to the gene for topoisomerase II alpha (TOP2A), a target for anthracyclines. We sought to understand the significance of these associated genomic changes for breast cancer prognosis and predicting response to therapy.

METHODS AND PATIENTS

Archival tissue samples from 63 breast cancer patients with ERBB2 amplification, stages 0-IV, were previously analyzed with FISH probes for genes located near ERBB2. In the present study, the clinical outcome data were determined for all patients presenting at stages I-III for whom adequate clinical follow up was available.

RESULTS

Four amplicon patterns (Classes) were identified. These were significantly associated with the clinical outcome, specifically, recurrence of breast cancer. The Amplicon class IV with deleted TOP2A had 67% (6/9) cases with recurrence, whereas the other three classes combined had only 12% (3/25) cases (p-value = 0.004) at the time of last follow-up. TOP2A deletion was also significantly associated with time to recurrence (p-value = 0.0002). After adjusting for age in Cox regression analysis, the association between TOP2A deletion and time to recurrence remains strongly significant (p-value = 0.002) whereas the association with survival is marginally significant (p-value = 0.06).

CONCLUSION

TOP2A deletion is associated with poor prognosis in ERBB2-amplified breast carcinomas. Clarification of the mechanism of this association will require additional study.

Immunohistochemical analysis of possible chemoresistance markers identified by micro-arrays on serous ovarian carcinomas

Using the DNA microarray technology, we have identified genes that are differentially expressed in chemosensitive and chemoresistant ovarian serous papillary carcinomas and could potentially distinguish ovarian cancer patients based on their response to chemotherapy. The present study aims to evaluate the clinical usefulness of overexpression of selected genes by immunohistochemistry. Our cohort included 158 women who were operated on and received chemotherapy for an advanced serous papillary ovarian carcinoma (FIGO stages III and IV). The end point used in this study was progression-free survival. Immunohistochemistry was performed on microarray blocks containing all 158 cases. Twelve commercially available antibodies were selected. Of them, 10 corresponded to differentially expressed genes in our micro-array study and p53 and Ki67 were included. Antibodies were obtained for the following selected genes: GSTA1, MMP1, FOSB, CTSL2, HSP10, CD36, CXCL2, RBBP7, Siva, and PTGDS. Cox proportional hazards models, adjusted for standard risk factors, were used to estimate the associations between the markers and progression-free survival. No association was found between mRNA level and protein expression by immunohistochemistry. In multivariate analyses, patients whose tumors overexpressed HSP10 had a lower risk of progression than those with low expression (HR: 0.6; CI: 0.42-0.87; P=0.007). High level of proliferation (Ki67) tended to be associated with a lower risk of progression (HR: 0.72; CI: 0.51-1.03; P=0.07) whereas MMP1 overexpression tended to be associated with a higher risk of progression (HR: 1.61; CI: 0.94-2.79; P=0.08). Our study shows that gene expression analysis coupled with immunohistochemistry allowed the identification of HSP10 as an independent factor of progression-free survival.

Tumor slices as a model to evaluate doxorubicin in vitro treatment and expression of trios of genes PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 in canine mammary gland cancer

Background

In women with breast cancer submitted to neoadjuvant chemotherapy based in doxorubicin, tumor expression of groups of three genes (PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2) have classified them as responsive or resistant. We have investigated whether expression of these trios of genes could predict mammary carcinoma response in dogs and whether tumor slices, which maintain epithelial-mesenchymal interactions, could be used to evaluate drug response in vitro.

Methods

Tumors from 38 dogs were sliced and cultured with or without doxorubicin 1 μM for 24 h. Tumor cells were counted by two observers to establish a percentage variation in cell number, between slices. Based on these results, a reduction in cell number between treated and control samples ≥ 21.7%, arbitrarily classified samples, as drug responsive. Tumor expression of PRSS11, MTSS1, CLPTM1 and SMYD2, was evaluated by real time PCR. Relative expression results were then transformed to their natural logarithm values, which were spatially disposed according to the expression of trios of genes, comprising PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. Fisher linear discrimination test was used to generate a separation plane between responsive and non-responsive tumors.

Results

Culture of tumor slices for 24 h was feasible. Nine samples were considered responsive and 29 non-responsive to doxorubicin, considering the pre-established cut-off value of cell number reduction ≥ 21.7%, between doxorubicin treated and control samples. Relative gene expression was evaluated and tumor samples were then spatially distributed according to the expression of the trios of genes: PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. A separation plane was generated. However, no clear separation between responsive and non-responsive samples could be observed.

Conclusion

Three-dimensional distribution of samples according to the expression of the trios of genes PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 could not predict doxorubicin in vitro responsiveness. Short term culture of mammary gland cancer slices may be an interesting model to evaluate chemotherapy activity.

Implications of applied research for prognosis and therapy of breast cancer

Breast cancer is the one of leading causes of cancer-related deaths in women within economically developed regions of the world. The heterogeneity of the natural history of breast cancer complicates patient management in that there is tremendous variability in response to treatment and for survival. More recently, several biomarkers (hormone receptor status and HER2 expression) have been added to the risk evaluation and therapeutic assessments. Evolving knowledge of molecular biology and newer techniques, such as genomics and proteomics, offer the potential to better define the biologic nature of the disease process, both for risk and therapy. This review discusses classical as well as new prognostic and predictive techniques. These are leading to a paradigm shift from empirical treatment to an individually tailored approach, which may soon become a realistic option for patients, based on specific molecular profiles.

Human epidermal growth factor receptor 2 status correlates with lymph node involvement in patients with estrogen receptor (ER) negative, but with grade in those with ER-positive early-stage breast cancer suitable for cytotoxic chemotherapy

PURPOSE

Human epidermal growth factor receptor 2 (HER-2) expression is associated with increased risk of high-grade disease, nodal metastasis, and absence of estrogen receptors (ERs) in early breast cancer. We tested interactions between ER and HER-2 to determine if they may modulate breast cancer nodal metastasis and proliferation.

PATIENTS AND METHODS

Tumors from the Cancer Research UK Taxotere as Adjuvant Chemotherapy phase III trial were tested for HER-2 using current diagnostic procedures. ER status, progesterone status, clinicopathologic characteristics, and patient age were included in a logistic regression analysis to identify associations with HER-2 status (positive v negative).

RESULTS

A total of 841 (23.6%) of 3,565 samples were HER-2 positive (3+ by immunohistochemistry or positive by fluorescent in situ hybridization). ER-negative tumors were more likely to be HER-2 positive than were ER-positive tumors (odds ratio [OR] = 1.87, ER negative v ER positive; P < .001). For ER-positive tumors, risk of HER-2 positivity increased by grade (OR = 7.6, grade 3 v grade 1; P < .001) but not nodal status (OR = 1.3, four or more positive nodes v node negative; P = .08). Conversely, ER negative node-positive tumors were markedly more frequently HER-2 positive than node-negative cases (OR = 3.05, four or more positive nodes v node negative; P < .001) but independent of grade (OR = 0.82, grade 3 v grade 1; P = .76).

CONCLUSION

In early breast cancer patients selected for cytotoxic chemotherapy, we identified significant interactions between HER-2 and ER expression that correlate with tumor pathology. In ER-positive breast cancers, HER-2 expression correlates with grade, not nodal metastasis. In ER-negative breast cancers, HER-2 expression correlates with increased nodal positivity, not grade. ER and HER-2 expression may modify tumor pathology via ER/HER-2-mediated cross talk.

HER-2, TOP2A and chromosome 17 alterations in breast cancer

HER-2 amplification is a biomarker for identifying patients who respond to trastuzumab and has been evaluated as a factor predicting the response to anthracyclines. The relationship between HER-2 and response to anthracycline therapy may also be the result of the close localization of TOP2A on 17q. It has been a matter of debate whether these two genes, HER-2 and TOP2A, behave separately on different amplicons or act together thus making it possible to predict the TOP2A status from the HER-2 status. In this study TOP2A, HER-2 and chromosome 17 aneusomy were investigated by fluorescent in situ hybridization (FISH) in 50 consecutive breast cancer patients. HER-2 amplification was detected in 11 patients (22%) and TOP2A changes were seen in 6 patients (12%); two amplifications and two deletions were observed in HER-2-amplified cases and two deletions in HER-2-nonamplified cases. Three of the TOP2A-deleted cases had polysomy 17. HER-2 copy number was higher than the TOP2A copy number in one patient with co-amplification. Polysomy was observed in 9 cases (18%) and monosomy in 6 cases (12%). Aneusomy was the sole anomaly in 11 patients (22%). We conclude that the TOP2A status cannot be predicted from the HER-2 status and evaluation of the TOP2A status only in patients with HER-2 overexpression may lead to missing cases with TOP2A deletion with possible resistance to therapy. Other factors modulating topo II activity may also affect the response to therapy. Studies evaluating different parameters that can modulate topo II activity and the response to the drugs targeting the enzyme are necessary.

Ki-67 expression in primary breast carcinomas and their axillary lymph node metastases: clinical implications

Proliferative activity of tumour cells assessed by immunohistochemical Ki-67 expression is one of several prognostic indicators in breast cancer. The major objective of this study was to investigate the prognostic impact of Ki-67 proliferative activity in the axillary lymph node metastases and in the matched primary breast carcinoma from 194 patients. There was a statistically significant up-regulation of Ki-67 protein in the metastatic deposit compared to where the primary tumour was found (p = 0.001). A low Ki-67 index in both the primary and the metastatic tumours was a favorable prognostic factor. A high index in both primary and metastatic lesion and an up-regulation from a low index in the primary tumour to a high index in the metastatic deposit represented an unfavorable prognostic factor. Multivariate analysis showed that Ki-67 expression in the metastases was a superior independent prognostic factor of clinical outcomes compared to that in the primary tumours. Ki-67 expression in > or =10% of carcinoma cells in the primary tumours and > or =15% in the nodal metastases seems to be optimal cut-off levels. Ki-67 is of value as an independent prognostic factor in breast cancer.

HER2 expression and efficacy of preoperative paclitaxel/FAC chemotherapy in breast cancer

PURPOSE

We examined the correlation between HER2 expression and pathologic complete response (pCR) to paclitaxel/FAC (T/FAC) preoperative chemotherapy in breast cancer.

PATIENTS AND METHODS

Retrospective analysis of data including 534 patients treated with preoperative T/FAC was performed. Gene expression results were available from two datasets of 132 and 286 patients, and were used to examine the co-expression of HER2 and topoisomerase II alpha (TOP2A) and microtubule associated protein tau (MAP-Tau).

RESULTS

Of the 534 patients, 105 (20%) had HER2-overexpressing breast cancer. The pCR rates were 33% and 15% for patients with HER2+ and HER2- tumors (P<0.001). The 5-year relapse-free survival rates were 94% and 70% in HER2+ tumors with and without pCR (P=0.009). HER2 overexpression (odds ratio 2.3, 95%CI: 1.3-3.9, P=0.004), estrogen receptor (ER) status, grade and weekly schedule of paclitaxel were each significantly and independently associated with pCR in multivariate analysis. When patients were stratified by ER status, the pCR rates were 50% for HER2+/ER-, 30% for HER2-/ER-, 19% for HER2+/ER+, and 6% for HER2-/ER+ tumors. HER2 overexpression was associated with lower expression of MAP-tau (P=0.001 and P<0.001) and higher expression of TOP2A mRNAs (P=0.048 and P=0.001) in patients with ER+ disease. ER- cancers had low MAP-tau expression regardless of HER-status.

CONCLUSION

HER2 overexpression is associated with higher rate of pCR to preoperative T/FAC chemotherapy regardless of ER status. HER2 overexpression also correlates with increased TOP2A and decreased MAP-tau expression in ER-positive cancers.

Grading invasive ductal carcinoma of the breast: advantages of using automated proliferation index instead of mitotic count

Breast carcinomas are graded according to the "Nottingham modification of the Bloom-Richardson system" (SBR). The system is hindered, however, by lack of precision in assessing all three parameters including nuclear grade, mitosis, and tubular formation, leading to an element of subjectivity. Our objective was to evaluate a new grading system [the nuclear grade plus proliferation (N+P) system] for subjectivity, ease, and better representation of tumor biology. Its components are nuclear grade and automated proliferation index. Invasive ductal carcinomas, consisting of 137 SBR grade I, 247 grade II, and 266 grade III, were re-evaluated by the N+P system. The two systems were compared with each other and correlated with patients' overall survival, tumor size, angiolymphatic invasion, lymph node status, and biomarker status including estrogen receptor, progesterone receptor, p53, epidermal growth factor receptor, BCL-2, and Her-2. Although there was an agreement between the two systems with histologic and prognostic parameters studied, there was 37% disagreement when grading individual tumors. Fifty-three percent of SBR grade II tumors were "down-graded" to N+P grade I, and 7% were "up-graded" to N+P grade III. Distinction among the different histologic grades for overall survival curves was better indicated by the N+P than the SBR system.

TOP2A and HER2 gene amplification as predictors of response to anthracycline treatment in breast cancer

The purpose of this study was to evaluate amplification of topoisomerase IIalpha (TOP2A) and HER2 genes as predictors of response to chemotherapy in advanced breast cancer. Gene copy number of TOP2A and HER2 were analysed with chromogenic in situ hybridization (CISH) on paraffin-embedded tissue sections from the primary tumour of 85 patients treated with anthracycline containing chemotherapy. TOP2A gene amplification was present in 14 (16%) and HER2 gene amplification in 38 (45%) of the primary tumours. Two of the 14 cases with TOP2A amplification were amplified without concurrent HER2 amplification. Neither TOP2A nor HER2 gene amplification were significantly associated with response to chemotherapy (p = 0.35 and p = 0.49, respectively).

Topoisomerase II alpha amplification may predict benefit from adjuvant anthracyclines in HER2 positive early breast cancer

BACKGROUND

TOP2A gene encodes topoisomerase II alpha, the direct molecular target of anthracyclines. This gene is frequently coamplified with HER2. The aims of this study were to analyse the pattern of TOP2A amplification and protein expression in relation to the molecular subgroups of breast cancers; and to define the impact of TOP2A amplification on the outcome of a series of patients homogeneously treated with adjuvant anthracyclines.

METHODS

A cohort of 245 patients with early breast cancer homogeneously treated with anthracyclines in the adjuvant setting was selected. A tissue microarray containing these cancers was used to determine HER2 and TOP2A gene copy number by means of chromogenic in situ hybridization. Immunohistochemical staining of topoisomerase II alpha was also performed using a monoclonal antibody (Ki-S1). TOP2A amplification and protein expression were correlated with classical prognostic parameters, expression of immunohistochemical markers and with a gene expression profiling classification using surrogate immunohistochemical markers. Kaplan-Meier method was used to construct survival curves and results were compared with log-rank test.

RESULTS

TOP2A amplification was restricted to tumours with HER2 amplification and was significantly associated with ER positivity. In the subgroup of patients with HER2 amplified tumours, TOP2A amplification predicted a better overall survival and disease free survival (P = 0.028 and 0.026, respectively). On multivariate analysis, TOP2A amplification maintained its predictive value for DFS.

CONCLUSION

TOP2A amplification is likely to be a useful marker to predict the subset of patients who will benefit from anthracyclines.