Immunologic proliferation marker Ki-S2 as prognostic indicator for lymph node-negative breast cancer

Predicting Neoadjuvant Treatment Response in Triple-Negative Breast Cancer Using Machine Learning

BACKGROUND

Neoadjuvant chemotherapy (NAC) is the standard treatment for early-stage triple negative breast cancer (TNBC). The primary endpoint of NAC is a pathological complete response (pCR). NAC results in pCR in only 30-40% of TNBC patients. Tumor-infiltrating lymphocytes (TILs), Ki67 and phosphohistone H3 (pH3) are a few known biomarkers to predict NAC response. Currently, systematic evaluation of the combined value of these biomarkers in predicting NAC response is lacking. In this study, the predictive value of markers derived from H&E and IHC stained biopsy tissue was comprehensively evaluated using a supervised machine learning (ML)-based approach. Identifying predictive biomarkers could help guide therapeutic decisions by enabling precise stratification of TNBC patients into responders and partial or non-responders.

METHODS

Serial sections from core needle biopsies (n = 76) were stained with H&E and immunohistochemically for the Ki67 and pH3 markers, followed by whole-slide image (WSI) generation. The serial section stains in H&E stain, Ki67 and pH3 markers formed WSI triplets for each patient. The resulting WSI triplets were co-registered with H&E WSIs serving as the reference. Separate mask region-based CNN (MRCNN) models were trained with annotated H&E, Ki67 and pH3 images for detecting tumor cells, stromal and intratumoral TILs (sTILs and tTILs), Ki67+, and pH3+ cells. Top image patches with a high density of cells of interest were identified as hotspots. Best classifiers for NAC response prediction were identified by training multiple ML models and evaluating their performance by accuracy, area under curve, and confusion matrix analyses.

RESULTS

Highest prediction accuracy was achieved when hotspot regions were identified by tTIL counts and each hotspot was represented by measures of tTILs, sTILs, tumor cells, Ki67+, and pH3+ features. Regardless of the hotspot selection metric, a complementary use of multiple histological features (tTILs, sTILs) and molecular biomarkers (Ki67 and pH3) resulted in top ranked performance at the patient level.

CONCLUSIONS

Overall, our results emphasize that prediction models for NAC response should be based on biomarkers in combination rather than in isolation. Our study provides compelling evidence to support the use of ML-based models to predict NAC response in patients with TNBC.

Predicting neoadjuvant treatment response in triple-negative breast cancer using machine learning

Background

Neoadjuvant chemotherapy (NAC) is the standard treatment for early-stage triple negative breast cancer (TNBC). The primary endpoint of NAC is a pathological complete response (pCR). NAC results in pCR in only 30%â€"40% of TNBC patients. Tumor-infiltrating lymphocytes (TILs), Ki67 and phosphohistone H3 (pH3) are a few known biomarkers to predict NAC response. Currently, systematic evaluation of the combined value of these biomarkers in predicting NAC response is lacking. In this study, the predictive value of markers derived from H&E and IHC stained biopsy tissue was comprehensively evaluated using a supervised machine learning (ML)-based approach. Identifying predictive biomarkers could help guide therapeutic decisions by enabling precise stratification of TNBC patients into responders and partial or non-responders.

Methods

Serial sections from core needle biopsies (n=76) were stained with H&E, and immunohistochemically for the Ki67 and pH3 markers, followed by whole slide image (WSI) generation. The resulting WSI triplets were co-registered with H&E WSIs serving as the reference. Separate mask region-based CNN (MRCNN) models were trained with annotated H&E, Ki67 and pH3 images for detecting tumor cells, stromal and intratumoral TILs (sTILs and tTILs), Ki67 + , and pH3 + cells. Top image patches with a high density of cells of interest were identified as hotspots. Best classifiers for NAC response prediction were identified by training multiple ML models, and evaluating their performance by accuracy, area under curve, and confusion matrix analyses.

Results

Highest prediction accuracy was achieved when hotspot regions were identified by tTIL counts and each hotspot was represented by measures of tTILs, sTILs, tumor cells, Ki67 + , and pH3 + features. Regardless of the hotspot selection metric, a complementary use of multiple histological features (tTILs, sTILs) and molecular biomarkers (Ki67 and pH3) resulted in top ranked performance at the patient level.

Conclusions

Overall, our results emphasize that prediction models for NAC response should be based on biomarkers in combination rather than in isolation. Our study provides compelling evidence to support the use of ML-based models to predict NAC response in patients with TNBC.

Assessment of mitotic activity in breast cancer: revisited in the digital pathology era

The assessment of cell proliferation is a key morphological feature for diagnosing various pathological lesions and predicting their clinical behaviour. Visual assessment of mitotic figures in routine histological sections remains the gold-standard method to evaluate the proliferative activity and grading of cancer. Despite the apparent simplicity of such a well-established method, visual assessment of mitotic figures in breast cancer (BC) remains a challenging task with low concordance among pathologists which can lead to under or overestimation of tumour grade and hence affects management. Guideline recommendations for counting mitoses in BC have been published to standardise methodology and improve concordance; however, the results remain less satisfactory. Alternative approaches such as the use of the proliferation marker Ki67 have been recommended but these did not show better performance in terms of concordance or prognostic stratification. The advent of whole slide image technology has brought the issue of mitotic counting in BC into the light again with more challenges to develop objective criteria for identifying and scoring mitotic figures in digitalised images. Using reliable and reproducible morphological criteria can provide the highest degree of concordance among pathologists and could even benefit the further application of artificial intelligence (AI) in breast pathology, and this relies mainly on the explicit description of these figures. In this review, we highlight the morphology of mitotic figures and their mimickers, address the current caveats in counting mitoses in breast pathology and describe how to strictly apply the morphological criteria for accurate and reliable histological grade and AI models.

Histological Grade in Breast Cancer: Association with Clinical and Biological Features in a Series of 229 Patients

In order to study the association of histological grade (HG) with specific clinical and biological parameters which may influence the clinical behavior of infiltrating ductal carcinomas of the breast (IDC), we analyzed in 229 tissue samples the cytosolic concentrations of estrogen receptor (ER), progesterone receptor (PR), pS2, cathepsin D, hyaluronic acid (HA) and tissue-type plasminogen activator (t-PA), as well as those of the erbB2 oncoprotein, epidermal growth factor receptor (EGFR), HA, CD44v5 and CD44v6 in the cell membrane fraction. Likewise, we considered size, ploidy, S-phase fraction and axillary node involvement as variables of the study. The transition from HG1 to HG2 and from HG2 to HG3 was accompanied by a number of common features: global increase in size, greater number of tumors >2.0 cm, decrease in membrane hyaluronic acid concentrations, increased cell proliferation (S-phase >7%) and greater aneuploidy. Other events observed during the transition from HG2 to HG3 were a decrease in ER, PR, t-PA and cytosolic hyaluronic acid. These results led us to consider that HG is associated with certain clinical-biological changes that may help explain its value as a prognostic factor in breast carcinomas.

The value of phosphohistone H3 as a proliferation marker for evaluating invasive breast cancers: A comparative study with Ki67

Background

Established measurements of proliferation in breast cancer are Ki67 and mitotic-activity-index (MAI), with problems in reproducibility and prognostic accuracy. Phosphohistone H3 (PHH3), a relatively novel IHC marker is specific for mitosis with good reproducibility. We hypothesized that PHH3 would be more reproducible and better represent proliferation than Ki67.

Results

PHH3 identified easily-missed mitosis by MAI, as demonstrated by upgrading M grade at diagnosis (n = 29/218, evenly distributed). PHH3 accurately found hot-spots, supported by mitotic count agreement between low-power and 10HPFs (R² = 0.999; P = 0.001). PHH3 was more reproducible than Ki67, measured by five-rater inter-class correlation coefficient (0.904 > 0.712; P = 0.008). Finally, despite a relatively short follow-up (median 46 months; 7 recurrences) PHH3 was the only variable correlated with disease-free survival (P = 0.043), while all other conventional clinicopathologic variables, including Ki67 (P = 0.356), did not.

Materials and Methods

We compared Ki67 and PHH3 for 218 breast cancer surgical cases diagnosed from 2012 to 2013 at Severance hospital. The most representative invasive breast cancer surgical slides were immunohistochemically stained for Ki67 and PHH3.

Conclusions

Poor reproducibility and inadequate representation of proliferation of Ki67 and MAI may be improved by PHH3, allowing better accuracy in breast cancer diagnostics.

Significance of immunohistochemistry in breast cancer

The biological characteristics of the tumour are used to estimate prognosis and select appropriate systemic therapy for patients with (breast) cancer. The advent of molecular technology has incorporated new biomarkers along with immunohistochemical and serum biomarkers. Immunohistochemical markers are often used to guide treatment decisions, to classify breast cancer into subtypes that are biologically distinct and behave differently, and both as prognostic and predictive factors. Steroid hormone receptors, markers of tumour proliferation, and factors involved in angiogenesis and apoptosis are of scientific interest. In this review we will provide information on the immunohistochemical markers used in the management of breast cancer patients using available data from the literature. We consider the utility of established immunohistochemical markers, and discuss the challenges involved in integrating novel molecular markers into clinical practice.

Significance of immunohistochemistry in breast cancer

The biological characteristics of the tumour are used to estimate prognosis and select appropriate systemic therapy for patients with (breast) cancer. The advent of molecular technology has incorporated new biomarkers along with immunohistochemical and serum biomarkers. Immunohistochemical markers are often used to guide treatment decisions, to classify breast cancer into subtypes that are biologically distinct and behave differently, and both as prognostic and predictive factors. Steroid hormone receptors, markers of tumour proliferation, and factors involved in angiogenesis and apoptosis are of scientific interest. In this review we will provide information on the immunohistochemical markers used in the management of breast cancer patients using available data from the literature. We consider the utility of established immunohistochemical markers, and discuss the challenges involved in integrating novel molecular markers into clinical practice.

Α-tubulin nuclear overexpression is an indicator of poor prognosis in patients with non-Hodgkin's lymphoma

In the present study, the newly established mouse monoclonal antibody, Y-49, binding to a specific epitope of α-tubulin, was used to examine immunohistochemical reactivity in 116 patients with non-Hodgkin's lymphoma (NHL). The protein was detected at elevated levels in the nuclei of human proliferating cells by western blot analysis, flow cytometry and immunohistochemical analysis. The relatively weak binding in the cytoplasm was evident in almost all cases. The investigation of the correlation between immuno-histochemical positivity and clinicopathological variables revealed links with the MIB-1 proliferation index and poor survival. Nuclear positivity with Y-49 was more frequent in older-aged patients, those with nodal NHL and in those who harbored the diffuse large B-cell histological subtype, and was strongly associated with high MIB-1 labeling indices (LIs). Survival analysis by the Kaplan-Meier method revealed statistically significant differences between patients with high and low Y-49 LIs (p=0.0181), even in the group with advanced (stage III/IV) disease (p=0.0327). Multivariate analysis revealed that overexpression of α-tubulin is an independent prognostic factor in NHL with a relative risk of 2.786.

A new Ki-67 / E-cadherin cocktail reduces inter-observer variation of the calculated proliferative index

The proliferative index in breast carcinoma is usually calculated by the percentage of the Ki-67 positive cells out of the total number of malignant cells. In order to reduce the inter-observer variability of the calculated proliferative index a cocktail of antibodies against E-Cadherin and Ki-67 (Ki/Cad Cocktail) is presented. The cocktail was applied on 59 cases of infiltrating duct carcinoma of breast and compared to the consecutive slides stained for Ki-67 alone. The Ki/Cad cocktail has the advantage that by adding the anti E-Cadherin antibody, all the malignant epithelial cells are highlighted and can be differentiated from other proliferating cells. Statistical analysis proved that the cocktail increases the inter-observer agreement from 89 % to 97 % as compared to the Ki-67 alone and also reduces the overlap between the cancer grades.

Ki-67: level of evidence and methodological considerations for its role in the clinical management of breast cancer: analytical and critical review

Clinicians can use biomarkers to guide therapeutic decisions in estrogen receptor positive (ER+) breast cancer. One such biomarker is cellular proliferation as evaluated by Ki-67. This biomarker has been extensively studied and is easily assayed by histopathologists but it is not currently accepted as a standard. This review focuses on its prognostic and predictive value, and on methodological considerations for its measurement and the cut-points used for treatment decision. Data describing study design, patients’ characteristics, methods used and results were extracted from papers published between January 1990 and July 2010. In addition, the studies were assessed using the REMARK tool. Ki-67 is an independent prognostic factor for disease-free survival (HR 1.05–1.72) in multivariate analyses studies using samples from randomized clinical trials with secondary central analysis of the biomarker. The level of evidence (LOE) was judged to be I-B with the recently revised definition of Simon. However, standardization of the techniques and scoring methods are needed for the integration of this biomarker in everyday practice. Ki-67 was not found to be predictive for long-term follow-up after chemotherapy. Nevertheless, high KI-67 was found to be associated with immediate pathological complete response in the neoadjuvant setting, with an LOE of II-B. The REMARK score improved over time (with a range of 6–13/20 vs. 10–18/20, before and after 2005, respectively). KI-67 could be considered as a prognostic biomarker for therapeutic decision. It is assessed with a simple assay that could be standardized. However, international guidelines are needed for routine clinical use.

Expression of targeting protein for Xenopus kinesin-like protein 2 is associated with progression of human malignant astrocytoma

In humans, the targeting protein for Xenopus kinesin-like protein 2 (TPX2) is a cell cycle-associated protein, and altered TPX2 expression has been found in various malignancies. However, the contribution of TPX2 expression to astrocytoma progression is unclear. The aim of this study was to investigate TPX2 expression in human astrocytoma samples and cell lines. TPX2 protein expression was detected in the nucleus of astrocytoma tissues by immunohistochemistry and immunofluorescence staining. Real-time PCR and Western blot analysis showed that the expression levels of TPX2 were higher in high-grade astrocytoma tissues and cell lines than that in low-grade astrocytoma tissues and normal cell lines. Immunohistochemical analysis of tumor tissues from 52 patients with astrocytoma showed that TPX2 over-expression was significantly associated with decreased patient survival. In addition, down-regulation of the TPX2 gene by RNA interference inhibited proliferation of U87 cells. TPX2 gene silencing also increased early-stage apoptosis in U87 cells. Western blotting and real-time PCR showed changes in the protein and mRNA expression of Aurora A, Ran, p53, c-Myc and cyclin B1 in U87 cells that had been transfected with pSUPER/TPX2/siRNA. These data suggest that TPX2 expression is associated with the progression of malignant astrocytoma.

The prognostic value of Ki67 is dependent on estrogen receptor status and histological grade in premenopausal patients with node-negative breast cancer

The aim of this study was to evaluate the prognostic value of Ki67 in relation to established prognostic factors in lymph node-negative breast cancer, and furthermore, whether the prognostic impact was dependent on estrogen receptor (ER) status and histological grade. In 200 premenopausal patients, with 5 years of follow-up, Ki67 was determined on tissue microarrays. In univariate analysis, Ki67 (< or = 20 vs >20%) was a prognostic factor for distant disease-free survival (hazard ratio: 2.7, 95% confidence interval: 1.3-5.4, P=0.005) and overall survival (hazard ratio: 4.9, 95% confidence interval: 1.7-14, P=0.003). When stratifying for ER status and histological grade, Ki67 was a significant prognostic factor for distant disease-free survival and overall survival only in the ER-positive group, and only in patients with histological grade 2, respectively. In multivariate analysis, human epidermal growth factor receptor 2 and age were independent prognostic factors for distant disease-free survival, whereas Ki67, histological grade, and tumor size were not. Ki67 was, however, an independent prognostic factor in the 87% of the patients who had not received adjuvant medical treatment. Agreement between the three readers was very good (kappa-values: 0.83-0.88). Furthermore, Ki67 was a significant prognostic factor for all three investigators (hazard ratio: 2.7-3.2). This study shows that Ki67 is a prognostic factor in node-negative breast cancer. It is noteworthy that the prognostic information of Ki67 is restricted to ER-positive patients, and to patients with histological grade 2. Taken together, Ki67, as an easily assessed and reproducible proliferation factor, may be an alternative or complement to histological grade as a prognostic tool and for selection of adjuvant treatment.

Preinvasive breast cancer

Preinvasive breast cancer accounts for approximately one-third of all newly diagnosed breast cancer cases in the United States and constitutes a spectrum of neoplastic lesions with varying degrees of differentiation and clinical behavior. High-throughput genetic, epigenetic, and gene-expression analyses have enhanced our understanding of the relationship of these early neoplastic lesions to normal breast tissue, and they strongly suggest that preinvasive breast cancer develops and evolves along two distinct molecular genetic and biological pathways that correlate with tumor grade. Although unique epigenetic and gene-expression changes are not observed in the tumor epithelial compartment during the transition from preinvasive to invasive disease, distinct molecular alterations are observed in the tumor-stromal and myoepithelial cells. This suggests that the stromal and myoepithelial microenvironment of preinvasive breast cancer actively participates in the transition from preinvasive to invasive disease. An improved understanding of the transition from preinvasive to invasive breast cancer will pave the way for novel preventative and therapeutic strategies.

Securin promotes the identification of favourable outcome in invasive breast cancer

Background:

Securin is a recently recognised oncogene with multiple known functions in initiation, progression and cell cycle regulation in several malignant diseases, including breast carcinoma.

Methods:

In this paper, the prognostic value of securin is evaluated by immunohistochemistry in 310 patients diagnosed with invasive breast cancer during a mammographic screening programme in Central Finland. All patients were directed to modern surgical and oncological treatments and were followed up for a maximum of 20 years.

Results:

Our results suggest that securin immunopositivity is an independent prognosticator of invasive breast cancer. In our study, securin predicted breast cancer-specific survival among all cases of invasive breast cancer and subgroups divided according to histological type, Ki-67 proliferation status and tumour size. Especially in a multivariate analysis standardised for axillary lymph node status, patient's age and tumour size at the time of diagnosis, securin immunopositivity indicated a 13.1-fold risk of breast cancer death (P=0.024) among invasive ductal breast carcinomas with low Ki-67 positivity.

Conclusion:

Our present and previous results suggest that securin could be useful in clinical pathology to intensify the power of the established prognosticators of invasive breast cancer and, especially, to assist in identifying patients with a more favourable outcome than that indicated by Ki-67 alone.

Ki-67 expression gives additional prognostic information on St. Gallen 2007 and Adjuvant! Online risk categories in early breast cancer

BACKGROUND

We sought to determine the significance of Ki-67, one of the tumor cell proliferation markers, as a useful prognostic factor in early breast cancer.

METHODS

A total of 1080 consecutive patients with stage I or II breast cancer that underwent surgery between 1998 and 2003 were enrolled. Patients were categorized on the basis of the 2007 St. Gallen consensus and Adjuvant! Online. The expression of Ki-67 in the tumor was assayed by immunohistochemistry (cutoff value, 10%).

RESULTS

Univariate analysis determined that tumor size, lymph node involvement, histologic grade, estrogen receptor, progesterone receptor, bcl-2, and Ki-67 (> or =10%) were statistically significant for both overall survival (OS) and distant metastasis-free survival (DFS). Of these factors, lymph node involvement and high Ki-67 expression were identified as independent prognostic factors for OS and DFS on the basis of multivariate analysis. The survivals of intermediate- and high-risk groups according to 2007 St. Gallen consensus were further separated by Ki-67 expression level (5-year DFS rate = 91.9% vs. 86.3% for Ki-67 < 10% and > or = 10%, respectively in intermediate-risk group (P = .01); 5-year DFS rate = 82.5% vs. 61.4% for Ki-67 < 10% and > or = 10%, respectively in high-risk group (P = .01)). The survivals of low- and high-risk groups according to Adjuvant! Online were further separated by Ki-67 expression level (5-year DFS rate = 97.8% vs. 89.5% for Ki-67 < 10% and > or = 10%, respectively in low-risk group (P = .02); 5-year DFS rate = 9.4% vs. 82.6% for Ki-67 < 10% and > or = 10% in high-risk group (P = .005)).

CONCLUSIONS

Ki-67 is an independent prognostic factor for DFS and OS in early breast cancer and can provide additional prognostic information on the risk stratification with the use of the 2007 St. Gallen consensus and Adjuvant! Online.

Proliferation markers and survival in early breast cancer: a systematic review and meta-analysis of 85 studies in 32,825 patients

We have performed a systematic review and meta-analysis of proliferation markers (Ki-67, mitotic index (MI), proliferating cell nuclear antigen (PCNA) and thymidine or bromodeoxyuridine labelling index (LI)) with respect to survival in early breast cancer. Eighty-five studies involving 32,825 patients were analysed. Ki-67 (43 studies, 15,790 patients), MI (20 studies, 7021 patients), and LI (11 studies, 7337 patients) were associated with significantly shorter overall and disease free survival, using results from univariate and multivariate analyses from the individual studies. PCNA (11 studies, 2677 patients) was associated with shorter overall survival by multivariate analysis only, because of lack of data. There was some evidence for publication bias, but all markers remained significant after allowing for this. Ki-67, MI, PCNA and LI are associated with worse survival outcomes in early breast cancer. However, whether these proliferation markers provide additional prognostic information to commonly used prognostic indices remains unclear.

Chromosome 20q amplification regulates in vitro response to Kinesin-5 inhibitor

We identified gene expression signatures predicting responsiveness to a Kinesin-5 (KIF11) inhibitor (Kinesin-5i) in cultured colon tumor cell lines. Genes predicting resistance to Kinesin-5i were enriched for those from chromosome 20q, a region of frequent amplification in a number of tumor types. siRNAs targeting genes in this chromosomal region identified AURKA, TPX2 and MYBL2 as genes whose disruption enhances response to Kinesin-5i. Taken together, our results show functional interaction between these genes, and suggest that their overexpression is involved in resistance to Kinesin-5i. Furthermore, our results suggest that patients whose tumors overexpress AURKA due to amplification of 20q will more likely resist treatment with Kinesin-5 inhibitor, and that inactivation of AURKA may sensitize these patients to treatment.

Tumor sclerosis but not cell proliferation or malignancy grade is a prognostic marker in advanced-stage follicular lymphoma: the German Low Grade Lymphoma Study Group

PURPOSE

Follicular lymphoma is an indolent lymphoma with a long median overall survival. However, a considerable number of patients die within the first 2 years after the onset of the disease. Because the treatment options vary with respect to antitumor effect and potential toxic adverse effects, the identification of high-risk patients would be helpful in directing therapeutic decisions in individual patients. Several histopathologic biomarkers for risk stratification have been suggested, but most markers have not been validated in patients treated in prospective trials.

PATIENTS AND METHODS

We report a comprehensive approach to evaluate histopathologic biomarkers, including WHO grade, histology, and proliferation and quantitation of immune bystander cells, in 158 patients with nodal advanced-stage follicular lymphoma treated first line within a randomized trial.

RESULTS

Tumor sclerosis was a significant prognostic marker of poor overall survival that was independent of the Follicular Lymphoma International Prognostic Index (FLIPI). WHO grade, proliferation, and total T-cell or macrophage content were not associated with overall survival.

CONCLUSION

The presence of sclerosis within the lymphoma is a marker of poor overall survival that is independent of the FLIPI. The quantification of macrophage or absolute T-cell content, grading, and proliferation are of no help in predicting the outcome of FL. Future studies need to identify surrogate markers for the prognostic immune signatures identified by gene expression profiling. Most importantly, new prognostic markers need to be confirmed in patients treated within prospective trials.

Regulation of repp86 stability by human Siah2

Human repp86 is a nuclear protein that is expressed in a tightly limited period of time during the cell cycle and plays an essential role in its progression. Manipulation of repp86 expression by reduction of endogenous repp86 or overexpression of exogenous repp86 results in cell cycle arrest. We found that repp86 interacts with human Siah2, which is a known mediator for proteasomal degradation. Siah2 failed to interact with repp86 lacking the first 67 N-terminal amino acids. Overexpression of Siah2 reduced endogenous and exogenous repp86 at the protein level without affecting its mRNA, as shown by cotransfection and RT-PCR experiments. Furthermore, MG-132--a specific inhibitor of the proteasome--blocked the degradation of repp86 in Siah2 overexpressing cells. Moreover, transiently transfected Siah2 abrogated the mitotic arrest in repp86 overexpressing cells. Our data show that Siah2 is an important mediator of repp86 protein degradation.

Ki-67 as prognostic marker in early breast cancer: a meta-analysis of published studies involving 12,155 patients

The Ki-67 antigen is used to evaluate the proliferative activity of breast cancer (BC); however, Ki-67's role as a prognostic marker in BC is still undefined. In order to better define the prognostic value of Ki-67/MIB-1, we performed a meta-analysis of studies that evaluated the impact of Ki-67/MIB-1 on disease-free survival (DFS) and/or on overall survival (OS) in early BC. Sixty-eight studies were identified and 46 studies including 12 155 patients were evaluable for our meta-analysis; 38 studies were evaluable for the aggregation of results for DFS, and 35 studies for OS. Patients were considered to present positive tumours for the expression of Ki-67/MIB-1 according to the cut-off points defined by the authors. Ki-67/MIB-1 positivity is associated with higher probability of relapse in all patients (HR=1.93 (95% confidence interval (CI): 1.74–2.14); P<0.001), in node-negative patients (HR=2.31 (95% CI: 1.83–2.92); P<0.001) and in node-positive patients (HR=1.59 (95% CI: 1.35–1.87); P<0.001). Furthermore, Ki-67/MIB-1 positivity is associated with worse survival in all patients (HR=1.95 (95% CI: 1.70–2.24; P<0.001)), node-negative patients (HR=2.54 (95% CI: 1.65–3.91); P<0.001) and node-positive patients (HR=2.33 (95% CI: 1.83–2.95); P<0.001). Our meta-analysis suggests that Ki-67/MIB-1 positivity confers a higher risk of relapse and a worse survival in patients with early BC.

Chemotherapy may be more effective in highly proliferative ovarian carcinomas—A translational research subprotocol of a prospective randomized phase III study (AGO-OVAR 3 protocol)

OBJECTIVE

Proliferative activity (PA) may be an indicator of a neoplasm's malignant potential, and it has been described as a prognostic factor in different malignant tumors. It was our aim to study the prognostic significance of PA defined by Ki-S5 and Ki-S2 immunohistochemical staining in a large homogeneously treated cohort with primary advanced-stage ovarian carcinomas.

METHODS

Immunohistochemical detection of PA was performed using monoclonal Ki-S5 and Ki-S2 antibodies and standard immunostaining protocols. Kaplan-Meier survival analysis and Cox regression multivariate analysis were performed.

RESULTS

High Ki-S5 PA was associated with a better prognosis. This finding was statistically significant after univariate and multivariate analysis. A similar trend was found in the subgroup of completely debulked patients. No prognostic effect of Ki-S2 PA could be detected in the present study.

CONCLUSION

High Ki-S5 PA is an indicator of a more favourable prognosis in patients with advanced ovarian carcinomas. Antiproliferative chemotherapy may be more effective in tumors which are highly proliferative, possibly due to an increased chemosensitivity.

Immunohistochemical biomarkers in patients with early-onset breast carcinoma by tissue microarray

Young women with breast cancer have a poor prognosis, and the role of biologic markers in young women is not well defined. We investigated the association of estrogen receptor, progesterone receptor, Bcl-2, HER-2/neu, p53, and Ki-67 with clinicopathologic features and outcome in young women with breast cancer.

METHODS

A cohort of 103 patients with early-onset breast cancer treated with conservative surgery and radiotherapy were entered in this study. Age range was 25-45 years, and median follow-up was 8.7 years. Each of the paraffin-embedded specimens was immunologically stained for six biomarkers expression by a recently developed tissue microarray method.

RESULTS

The 10-year overall breast relapse-free and distant relapse-free survival rates were 82.7%, 84.6.4%, and 66.7%, respectively, with 14 local relapses and 26 distant metastases among the 103 patients evaluated. Positive expression of estrogen receptor, progesterone receptor, bcl-2, HER-2/neu, p53, and Ki-67 were 42.7%, 48.5%, 35.6%, 28.0%, 36.9%, and 39.7%, respectively. Tumor stage and nodal status were significantly associated with overall survival and distant metastasis-free rate in univariate and multivariate analysis. Progesterone receptor negativity and Ki-67 positivity were associated with distant metastasis. There was no statistically significant correlation between the six biomarkers and local relapse.

CONCLUSIONS

Progesterone receptor, Ki-67, tumor stage, and nodal status were prognostic factors for distant failure in early-stage breast cancer in young patients. Further studies are needed to find other biologic markers associated with local failure in this group of patients.

Repp86: a new prognostic marker in mantle cell lymphoma

OBJECTIVES

Proliferation indices are important prognostic factors for the clinical outcome of patients with mantle cell lymphoma (MCL). We investigated whether the expression of repp86 (restrictedly expressed proliferation-associated protein 86 kDa), a new proliferation specific marker expressed in the cell cycle phases G(2), S and M, but not in G(1), correlates with the clinical course in patients with MCL.

PATIENTS AND METHODS

Biopsy specimens from 94 untreated patients enrolled in two multicenter trials were investigated immunohistochemically with monoclonal antibodies against CD20, CD5, CD3, CD23, cyclin D1, and repp86 (Ki-S2).

RESULTS

Patients with 0-1% repp86 expression had a median overall survival time of 71.0 months, compared with 38.2 months for patients with 1-5% positive cells and 25.4 months for patients with 5-10% positive tumor cells. Patients with repp86 expression of more than 10% showed the shortest survival (median: 15.0 months). Kaplan-Meier analysis revealed a significant difference in the overall survival time between patients with very high (>10%) and very low (0-1%) repp86 expression (P < 0.0001) in the tumor cells. The multivariate analysis revealed repp86 expression to be superior to other clinical characteristics as a prognostic factor (P = 0.0016).

CONCLUSION

Based on these findings, repp86 expression is a new important prognostic factor in MCL.

Proliferation marker Ki-67 in early breast cancer

Molecular markers have been extensively investigated with a view to providing early and accurate information on long-term outcome and prediction of response to treatment of early breast cancer. Proliferation is a key feature of the progression of tumors and is now widely estimated by the immunohistochemical assessment of the nuclear antigen Ki-67. The expression of Ki-67 correlates with other measurements of proliferation, including S-phase and bromodeoxyuridine uptake. High Ki-67 is a sign of poor prognosis associated with a good chance of clinical response to chemotherapy, but its independent significance is modest and does not merit measurements in most routine clinical scenarios. However, its application as a pharmacodynamic intermediate marker of the effectiveness of medical therapy holds great promise for rapid evaluation of new drugs.

[Combined flow cytometry determination of S-phase fraction and DNA ploidy is an independent prognostic factor in node-negative invasive breast carcinoma: review of a series of 271 patients with stage I and II breast cancer]

PURPOSE

To assess the significance of S-phase fraction (SPF) and DNA ploidy evaluated by DNA flow cytometry as prognostic markers in stage I or II breast cancer.

PATIENTS AND METHODS

A series of 271 patients, treated by surgery, radiotherapy+/-systemic therapy was analysed (median follow up: 64 months). Standardized flow cytometry cell preparation from frozen samples and consensus rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. Four groups were defined based on combinations of DNA ploidy (DIP: diploid; ANEUP: aneuploid) and SPF: DIP and low SPF (DL, N=37), DIP and medium or high SPF (DMH, N=76), ANEUP and low SPF (AL, N=24), ANEUP and medium or high SPF (AMH, N=68). Local control rate (LCR), disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS) were correlated with DNA ploidy, SPF, DL to AMH groups, T and N stages, SBR grading, age, and hormonal status on univariate and multivariate analysis (Cox model).

RESULTS

On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N- patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N- stage I and II breast cancer.

Breast carcinoma malignancy grading by Bloom-Richardson system vs proliferation index: reproducibility of grade and advantages of proliferation index

Questions of reproducibility and efficacy of histologic malignancy grading relative to alternative proliferation index measurements for outcome prediction remain unanswered. Microsections of specimens from the Cooperative Breast Cancer Tissue Resource (CBCTR) were evaluated by seven pathologists for reproducibility of grade and classification. Nuclear figure classification was assessed using photographs. Grade was assigned by the Bloom-Richardson method, Nottingham modification. Proliferation index was evaluated prospectively by deoxyribose nucleic acid precursor uptake with thymidine (autoradiographic) or bromodeoxyuridine (immunohistochemical) labeling index using fresh tissue from 631 node-negative breast cancer patients accessioned at St Luke's Hospital. A modified Nottingham-Bloom-Richardson grade was derived from histopathologic data. Median post-treatment observation was 6.4 years. Agreement on classification of nuclear figures (N=43) was less than good by kappa statistic (kappa=0.38). Grade was moderately reproducible in four trials (N=10,10,19, 10) with CBCTR specimens (kappa=0.50-0.59). Of components of Bloom-Richardson grade, agreement was least for nuclear pleomorphism (kappa=0.37-0.50), best for tubularity (kappa=0.57-0.83), and intermediate for mitotic count (kappa=0.45-0.64). Bloom-Richardson grade was a univariate predictor of prognosis in node-negative St Luke's patients, and was improved when mitotic count was replaced by labeling index (low, mid, or high). When labeling index was added to a multivariate model containing tumor size and vessel invasion, grade was no longer a significant predictor of tumor-specific relapse-free or overall survival. Mitotic index predicted best when intervals were lowered to 0-2, 3-10, and >10 mitotic figures per ten 0.18 mm(2) high-power fields. We conclude that Nottingham-Bloom-Richardson grades remain only modestly reproducible. Prognostically useful components of grade are mitotic index and tubularity. The Nottingham-Bloom-Richardson system can be improved by lowering cutoffs for mitotic index and by counting 20-30 rather than 10 high-power fields. Measurement of proliferation index by immunohistochemically detectable markers will probably give superior prognostic results in comparison to grade.

Combined flow cytometry determination of S-phase fraction and DNA ploidy is an independent prognostic factor in node-negative invasive breast carcinoma: analysis of a series of 271 patients with stage I and II breast cancer

PURPOSE

To assess the significance of S-phase fraction (SPF) and DNA ploidy evaluated by DNA flow cytometry as prognostic markers in stage I or II breast cancer.

PATIENTS AND METHODS

A series of 271 patients, treated by surgery, radiotherapy +/- systemic therapy was analyzed (median follow up: 64 months). Standardized flow cytometry cell preparation from frozen samples and consensus rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. Four groups were defined based on combinations of DNA ploidy (DIP: diploid; ANEUP: aneuploid) and SPF: DIP and low SPF (DL, n=37), DIP and medium or high SPF (DMH, n=76), ANEUP and low SPF (AL, n=24), ANEUP and medium or high SPF (AMH, n=68). Local control rate (LCR), disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS) were correlated with DNA ploidy, SPF, DL to AMH groups, T and N stages, SBR grading, age, and hormonal status on univariate and multivariate analysis (Cox model).

RESULTS

On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N- patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N- stage I and II breast cancer.

Development of a novel method for measuring in vivo breast epithelial cell proliferation in humans

Cell proliferation plays an important role in all stages of carcinogenesis. Currently, no safe, direct, in vivo method of measuring breast epithelial cell (BEC) proliferation rates in humans exists. Static immunohistochemical markers of cell proliferation, such as Ki-67 and PCNA indices, have technical limitations including high inter-lab variability, inaccuracy in the presence of agents that cause G1/S cell cycle block and inadequate sensitivity in post-menopausal women with low BEC proliferation rates. We describe here a safe, direct method of measuring BEC proliferation rates in vivo in women using heavy water ((2)H(2)O) labeling coupled with mass spectrometric analysis. Proliferation of normal and tumor BEC was measured from breast tissue biopsies in women undergoing mastectomy (n = 11) and normal BEC from healthy volunteers (n = 16). Women took heavy water (50-150 ml per day) for 1-4 weeks. Pre-menopausal women had significantly higher proliferation rates than post-menopausal women (0.7 +/- 0.1 versus 0.2 +/- 0.1 new cells per day, respectively), and tumor BEC had different proliferation rates than normal BEC from the same breast. The method is analytically reproducible and remains sensitive in the range of low proliferation rates. In summary, this novel method of measuring BEC proliferation in vivo holds promise for assessing the effects of anti-proliferative chemopreventive and chemotherapeutic agents.

The superior prognostic value of humoral factors compared with molecular proliferation markers in renal cell carcinoma

BACKGROUND

The American Joint Committee on Cancer and the Union Internationale Contre le Cancer have acknowledged routine laboratory parameters, such as serum calcium, alkaline phosphatase, hemoglobin, and the erythrocyte sedimentation rate (ESR), as predictors of survival in patients with renal cell carcinoma. The predictive value of these parameters compared with proliferation markers, such as Ki-67, proliferating cell nuclear antigen (PCNA), topoisomerase II-alpha, and p100, has not been determined.

METHODS

Forty-eight consecutive patients who underwent nephrectomy for nonmetastatic renal cell carcinoma between 1990 and 1994 were observed up to 120 months postoperatively. Ten of 48 patients developed tumor progression 6-69 months after surgery. Routine preoperative laboratory parameters as well as tumor-specific data were assessed. Findings were compared with tumor proliferation indices, which were obtained by immunohistochemical staining for nuclear antigens Ki-67, PCNA, topoisomerase II-alpha, and p100 in paraffin embedded tumor tissue.

RESULTS

Univariate and multivariate statistical analyses demonstrated superiority of routine laboratory values compared with tumor proliferation indices in predicting progression-free survival and disease-specific death. The best predictor after tumor size and symptomatic presentation was ESR (P < 0.0001), with ESR values > 70 mm at 2 hours indicating a significantly poorer prognosis. Only the proliferation marker Ki-67 reached univariate significance at a threshold of 7%.

CONCLUSIONS

Routine laboratory parameters, such as alkaline phosphatase, lactate dehydrogenase, thrombocyte count, and especially ESR, provided superior long-term prognostic information for patients with nonmetastatic renal cell carcinoma compared with the molecular tumor proliferation markers Ki-67, PCNA, topoisomerase II-alpha, and p100.

Repp86 expression and outcome in patients with neuroblastoma

PURPOSE

Given the well-known challenges of neuroblastoma prognosis, we investigated whether the expression of restrictedly expressed proliferation-associated protein of 86 kDa theoretical molecular mass (repp86), a proliferation-associated protein expressed in S, G2, and M phases of the cell cycle, correlates with the clinical outcome in patients with neuroblastoma.

PATIENTS AND METHODS

161 children with different stages of neuroblastoma were studied; the median follow-up time was 72.8 months. The patients were staged according to the International Neuroblastoma Staging System, and histologic grading of the tumors was performed according to the criteria of Hughes and those of the International Neuroblastoma Pathology Classification. The MYCN gene copy number was determined by Southern blot analysis or fluorescence in situ-hybridization, and repp86 expression was assessed immunohistochemically by means of monoclonal antibody Ki-S2 on paraffin sections from archival tumor samples.

RESULTS

A repp86 labeling index (RI) of more than 10% positive tumor cells significantly predicted a shortened disease-free interval and an increased tumor mortality (both P <.0001). Moreover, the RI allowed the identification of patients with favorable and adverse prognosis in subsets defined by stage, grade, age, and MYCN status. In a multivariate analysis, the RI emerged as the most important predictor of event-free and disease-specific survival with hazard ratios of 11.7 and 10.5, respectively (both P <.0001).

CONCLUSION

It seems that repp86 expression is closely associated with the biologic behavior of neuroblastoma. Assessment of the RI might, therefore, considerably refine prognostic models.

Significance of nodal metastatic tumor characteristics in nodal metastasis and prognosis of patients with invasive ductal carcinoma of the breast

There is no study evaluating the significance of nodal metastatic tumor characteristics in tumor progression of invasive ductal carcinomas (IDCs) of the breast. The purpose of this study was to investigate whether nodal metastatic tumor characteristics play an important role in the tumor progression of IDCs. The subjects of this study were 205 IDC patients with nodal metastases. Significant associations with increased numbers of nodal metastases, and patient outcomes were evaluated by multivariate analyses, in comparison with well-known histological parameters. The numbers of lymph nodes with extra-nodal invasion and with extranodal blood vessel tumor emboli, the distance of extra-nodal blood vessel tumor emboli from the nodes, and the nodal tumor dimensions significantly increased the number of nodal metastases in the multivariate analysis (P<0.001). Cox multivariate analyses showed that the parameters which significantly increased hazard rates (HRs) of disease-free survival (DFS), distant organ metastasis (DOM) and overall survival were 6 or more mitotic figures of nodal metastatic tumors (P<0.05). Six or more lymph nodes with extra-nodal invasion, and an extra-nodal blood vessel tumor emboli dimension of >0.6 mm significantly increased the HRs of DFS and DOM in multivariate analyses (P<0.05). The present study demonstrated the important roles of nodal metastatic tumors in the tumor progression of IDCs.

Large scale identification of human hepatocellular carcinoma-associated antigens by autoantibodies

Autoantibodies are often detected in hepatocellular carcinoma (HCC), and these responses may represent recognition of tumor Ags that are associated with transformation events. The identities of these Ags, however, are less well known. Using serological analysis of recombinant cDNA expression libraries (SEREX) from four HCC patients, we identified 55 independent cDNA sequences potentially encoding HCC tumor Ags. Of these genes, 15 are novel. Two such proteins, HCA587 and HCA661, were predominantly detected in testis, but not in other normal tissues, except for a weak expression in normal pancreas. In addition to HCC, these two Ags can be found in cancers of other histological types. Therefore, they can be categorized as cancer-testis (CT) Ags. Two other Ags (HCA519 and HCA90) were highly overexpressed in HCC and also expressed in cancer cell lines of lung, prostate, and pancreas, but not in the respective normal tissues. Four other Ags were identified to be expressed in particular types of cancer cell lines (HCA520 in an ovarian cancer cell line, HCA59 and HCA67 in a colon cancer cell line, HCA58 in colon and ovarian cancer cell lines), but not in the normal tissue counterpart(s). In addition, abundant expression of complement inactivation factors was found in HCC. These results indicate a broad range expression of autoantigens in HCC patients. Our findings open an avenue for the study of autoantigens in the transformation, metastasis, and immune evasion in HCC.

Correlation between MIB-1 and other proliferation markers: clinical implications of the MIB-1 cutoff value

BACKGROUND

Cell proliferation is a major determinant of the biologic behavior of breast carcinoma. MIB-1 monoclonal antibody is a promising tool for determining cell proliferation on routine histologic material. The objectives of this study were to compare MIB-1 evaluation to other methods of measuring cell proliferation, with a view to refining the cutoff used to classify tumors with low and high proliferation rates in therapeutic trials.

METHODS

One hundred eighty-five invasive breast carcinomas were evaluated for cell proliferation by determining monoclonal antibody MIB-1 staining, histologic parameters (Scarff-Bloom-Richardson grade and mitotic index) on paraffin sections, S-phase fraction (SPF) by flow cytometry, and thymidine-kinase (TK) content of frozen samples.

RESULTS

There was a high correlation (P = 0.0001) between the percentage of MIB-1 positive tumor cells and SPF, TK, histologic grade, and the mitotic index. Multivariate analyses including MIB-1 at 5 different cutoffs (10%, 15%, 17% [median], 20%, 25%) and the other proliferative markers showed that the optimal MIB-1 cutoff was 25% and that the mitotic index was the proliferative variable that best discriminated between low and high MIB-1 samples. A MIB-1 cutoff of 25% adequately identified highly proliferative tumors. Conversely, with a MIB-1 cutoff of 10%, few tumors with low proliferation were misclassified.

CONCLUSIONS

The choice of MIB-1 cutoff depends on the following clinical objective: if MIB-1 is used to exclude patients with slowly proliferating tumors from chemotherapeutic protocols, a cutoff of 10% will help to avoid overtreatment. In contrast, if MIB-1 is used to identify patients sensitive to chemotherapy protocols, it is preferable to set the cutoff at 25%. The MIB-1 index should be combined with some other routinely used proliferative markers, such as the mitotic index.

Prognostic significance of tumor cell proliferation analyzed in fine needle aspirates from primary breast cancer

The objective of this study was to analyze the role of proliferating fraction (PF) measured with Ki-67/MIB-1 antibody in a large series of preoperative fine-needle aspirate (FNA) biopsies as a prognosticator of disease recurrence. The study comprised 732 patients who all had a conclusive cytological diagnosis of breast cancer. The follow-up time ranged from 1.2 to 10.2 years with a median of 5.7 years. In multivariate analysis Ki-67/MIB-1 value was a strong (p < 0.001) significant, prognosticator of disease recurrence free interval (DRFI) independent of lymph node status, progesterone receptor content, and tumor size. In the subgroup analysis of 430 node-negative patients the distant recurrence-free rate after 5 years was 94.4% in patients with Ki-67/MIB-1 value < 15% compared to 88.7% in patients with Ki-67/MIB-1 value > or = 15% (p = 0.03). Test of the interaction between tumor size and the value of PF revealed a p-value of 0.06. If the patients, in addition, had a tumor size >20 mm the distant recurrence-free rate after 5 years was 93.2% if Ki-67/MIB-1 < 15% compared to 80.7% in patients with Ki-67/MIB-1 value > or = 15%. This difference was statistically significant (p < 0.01). For patients with tumors <20mm Ki-67/MIB-1 value did not add any prognostic information. In the subgroup of 302 node-positive patients the distant recurrence-free rate after 5 years was 86.0% in patients with Ki-67/MIB-1 value < 15% compared to 70.6% in patients with Ki-67/MIB-1 value > or = 15% (p < 0.01). We conclude that PF assessed by Ki-67/MIB-1 antibodies in preoperative FNA biopsies has a significant prognostic value independent of lymph node status, PgR status and tumor size. To our knowledge, this is the first study demonstrating PF, which can contribute prognostic information when analyzed in preoperative smears.

[Infiltrating ductal carcinomas of the breast in women over 60 years of age. Association with higher cellular proliferation and lower PS2, cell surface and cytosolic hyaluronic acid concentrations]

INTRODUCTION

There are several discrepancies in the literature concerning breast cancer behavior in elderly women. For this reason, we decided to study the possible clinical-biological differences between infiltrating ductal breast carcinomas in women older than 60 and those between 41 and 60 years old.

PATIENTS AND METHODS

The study group included 161 women with infiltrating ductal carcinomas of the breast, 90 of whom were women over 60 years and 71 whose ages ranged from 41 to 60 years old. Estrogen receptors (ER), progesterone receptors (PR), pS2, cathepsin D, tissue-type plasminogen activator (t-PA) and hyaluronic acid (HA) cytosolic concentrations were analyzed in addition to those of the epidermal growth factor receptor (EGFR), HA and erbB2/neuoncoprotein in cell surfaces. Size, axillary lymph node involvement, distant metastases, histological grade, ploidy and cellular S-phase fraction were also considered as study variables.

RESULTS

Infiltrating ductal carcinomas of the breast in women over 60 had lower pS2 concentrations (p: 0.0367), cell surface (p: 0.021) and cytosolic hyaluronic acid (p: 0.0019) levels than those of women whose ages ranged from 41 to 60 years old. Furthermore, the former had higher S-phase values (p: 0.0345) and percentage of cases with S-phase >7% (p: 0.0483).

CONCLUSIONS

The results obtained (higher cellular proliferation and lower pS2, cell surface and cytosolic hyaluronic acid concentrations) suggest that the infiltrating ductal carcinomas of the breast in women older than 60 could have a worse behavior, as has been suggested by other authors, even though further studies with more patients would be needed in order to observe if these biological differences still persist.

Thymidine kinase as a proliferative marker: clinical relevance in 1,692 primary breast cancer patients

PURPOSE

To assess the prognostic value of thymidine kinase (TK), an enzyme involved in the DNA synthesis salvage pathway, relative to other prognostic factors in primary breast cancer.

PATIENTS AND METHODS

This retrospective study involved 1,692 patients with operable breast cancer treated in six institutions (median follow-up, 82 months). Among the 857 node-negative patients, 135 received adjuvant chemotherapy (fluorouracil, doxorubicin, cyclophosphamide [FAC] or fluorouracil, etoposide, and cisplatin [FEC]). TK was assayed in cytosol with a quantitative radioenzymatic technique. Disease-specific survival (DSS), local recurrence-free interval (LRI), and distant-relapse-free interval (DRI) were investigated.

RESULTS

High TK levels were associated with large tumor size, high histologic grade, and steroid hormone receptor negativity. Univariate analysis of the entire data set showed that high TK levels were related to shorter DSS (P < 10(-5)), LRI (P < 10(-3)), and DRI (P < 10(-5)). In time-dependent Cox models, high TK levels remained an independent predictor of the three outcomes, both in the overall population and in node-negative patients, although its prognostic value decreased over time. In node-negative patients, the introduction of an interaction term in multivariate analysis suggested that chemotherapy was more efficacious for patients who had tumors with high TK contents. In node-positive patients, high TK levels were related only to an increased risk of LRI.

CONCLUSION

High TK values are an important risk factor in node-negative patients and seem to be associated with a beneficial effect of adjuvant FAC or FEC in patients who received adjuvant chemotherapy. The rationale of chemotherapy for patients with slowly proliferating tumors has to be discussed from a risk-benefit point of view.

Ductal invasive G2 and G3 carcinomas of the breast are the end stages of at least two different lines of genetic evolution

Ductal invasive grade (G) 2 and G3 carcinomas represent the majority of invasive breast cancers. Previous morphological and cytogenetic studies have provided evidence that ductal invasive G2 carcinoma may originate from at least two different genetic pathways. The aim of this study was to evaluate further the heterogeneity of G2 breast cancer in comparison with G3 cancers by cytogenetic and quantitative analysis. To this end, 35 cases of ductal invasive G2 and 42 cases of ductal invasive G3 carcinomas were investigated by means of comparative genomic hybridization (CGH) and these findings were correlated with DNA ploidy status, mitotic activity index (MAI), mean nuclear area (MNA), volume per lumen (VPL), and clinico-pathological parameters. The findings of this study demonstrate that ductal invasive G2 carcinomas, in contrast to ductal invasive G3 carcinomas, have to be interpreted as the morphological end stage resulting from two different cytogenetic and morphological pathways; the loss of 16q material is the cytogenetic key event in the evolution of a subgroup of this entity. By correlating genetic alterations with DNA ploidy status, an extended morphology-based cytogenetic progression model is presented, with early and late genetic alterations in the pathogenesis of breast cancer. The correlation with MAI gives rise to the hypothesis that these different genetic pathways significantly differ in their proliferation rate. Further studies will be required to elucidate which genes contribute to an altered proliferation rate in these subgroups and to the associated prognosis.

Cell Proliferation in Ovarian Carcinoma: Superior Accuracy of S-Phase Fraction (SPF) by DNA Labeling Index versus Flow Cytometric SPF, Lack of Independent Prognostic Power for SPF and DNA Ploidy, and Limited Effect of SPF on Tumor Growth Rate

OBJECTIVES

The goal of this work was to test the hypotheses that S-phase fraction (SPF) by DNA labeling index (SPF-LI) would predict the course of the disease for ovarian/peritoneal carcinomas and that SPF-LI would correlate better with pathologic classification and outcome than SPF by DNA flow cytometry (SPF-F).

METHODS

Tritiated thymidine (1985-1988) and bromodeoxyuridine (1988-1999) DNA labeling (SPF-LI) was evaluated in vitro on 178 tumors. Cellular DNA and SPF-F were measured flow cytometrically. During this time, 90% of ovarian/peritoneal tumors accessioned in surgical pathology were studied.

RESULTS

Tumors of low malignant potential (LMP, "borderline") had low SPF-LI (median = 1.2%). High-grade invasive carcinomas of various types and carcinosarcomas all had high SPF-LI (medians = 11.2-23.4%). Serous low-grade invasive carcinomas (median = 1.05) resembled LMP tumors. SPF-LI of ovarian carcinomas other than LMP tumors increased slightly as FIGO stage increased (P = 0.07). Survival of patients with high-grade ovarian carcinomas was not predicted by SPF-LI or SPF-F, nor was DNA ploidy predictive. SPF-LI produced tighter distributions for various tumor types than did SPF-F. Neither SPF nor DNA ploidy contributed to prediction of outcome when tumor type and stage were included in multivariate models. We calculated the mean cell loss rate of high-grade carcinomas to be 94%.

CONCLUSIONS

LMP ovarian/peritoneal tumors have low proliferation rates in contrast to high-grade carcinomas. Proliferation correlated with tumor type and stage, but neither it nor DNA ploidy predicted survival independently. Proliferation rate is growth limiting only when low. At higher levels cell loss limits growth. SPF-LI measures proliferation more accurately than SPF-F; SPF-F is not sufficiently reliable for clinical use.

Telomerase, immortality and cancer

Replication of eukaryotic linear chromosomes is incomplete and leaves terminal gaps. The evolutionary widely distributed solution to this "end replication" is twofold: chromosome ends are capped with telomeres, bearing multiple copies of redundant telomeric sequences, and the telomerase enzyme can add (lost) telomeric repeats. Telomerase in humans, as in all mammals, is ubiquitous in all embryonic tissues. In adults, telomerase remains active in germs cells, and, although down-regulated in most somatic tissues, telomerase is active in regenerative tissues and notably, in tumor cells. Telomerase activity is linked to cellular proliferation, and its activation seems to be a mandatory step in carcinogenesis. In contrast to mammals, indeterminately growing multicellular organisms, like fish and crustaceae, maintain unlimited growth potential or 'immortality' in all somatic tissues throughout their entire life. Also this cell immortalization is brought about by maintaining telomerase expression. Disease prognosis for human tumors includes evaluation of cell proliferation, based on the detection of proliferation markers with monoclonal antibodies. The significance of the classical marker Ki-67, and of a novel marker repp-86 are compared with semiquantitative telomerase assays. For tumor therapy, telomerase inhibitors are attractive tools. Results with telomerase knock-out mice have revealed promise, but also risk of this approach. On the other side, telomerase stimulation is attractive for expanding the potential of cellular proliferation in vitro, with possible applications for transplantation of in vitro expanded human cells, for immortalizing primary human cells as improved tissue models, and for the isolation of otherwise intractable products, like genuine human monoclonal antibodies.

Concurrent overexpression of p53 and c-erbB-2 correlates with accelerated cycling and concomitant poor prognosis in node-negative breast cancer

Simultaneous overexpression of c-erbB-2 and p53 has been reported to be prognostically unfavorable in breast cancer. Herein, we show that concurrent overexpression of these 2 proteins is associated with a marked reduction in the relative fraction of cells in G(1) phase of the cell cycle, indicating an accelerated cell cycle progression. Using an immunohistochemical approach, we examined 261 cases of node-negative infiltrating ductal carcinomas of the breast with respect to c-erbB-2 and p53 expression and to the proliferative activity measured by the Ki-67 index. By means of a novel monoclonal antibody, Ki-S2, which exclusively recognizes proliferating cells in the S, G(2), and M phases of the reproductive cycle, we were further able to calculate the relative fraction of the cells having passed the restriction point at the G(1)/S boundary, thus defining a cycling ratio (CR). The results were correlated with clinical outcome; median follow-up time was 96 months. Tumors that simultaneously overexpressed c-erbB-2 and p53 had a high median CR and followed an unfavorable course. However, increased CRs were also observed independently of c-erbB-2 and p53 overexpression, suggesting that other molecular mechanisms may contribute to acceleration of cell cycle progression. In a multivariate analysis that included patient age, tumor size, hormone receptor status, c-erbB-2 and p53 expression, and the Ki-67 index, CR emerged as the most significant independent predictor of overall and disease-free survival (P <.0001). It is concluded that the CR is a gauge of cell cycle deregulation and therefore may be a powerful indicator of the biologic behavior of cancers. HUM PATHOL 32:311-319.

Low proliferative rate of invasive node-negative breast cancer predicts for a favorable outcome: a prospective evaluation of 669 patients

This study was designed to compare outcome in terms of disease-free survival (DFS) in women with histologically negative axillary lymph nodes and documented low proliferative rate cancer to other well-defined prognostic factors including type of adjuvant treatment. Between 1988 and 1998, we studied 669 patients with invasive node-negative breast cancer up to 5 cm in size and low proliferative rate measured by flow cytometry to determine S-phase fraction (SPF) or by histochemistry (Ki67/MIB1). At a median follow-up of 53 months, 5-year DFS for the entire group was 94% and did not differ significantly by type of systemic adjuvant treatment: none (133 patients, 95% DFS), tamoxifen (441 patients, 94% DFS), or chemotherapy with doxorubicin and cyclophosphamide (95 patients, 92% DFS). In a multivariate prognostic factor analysis, only tumor size was significant; 5-year DFS was 96% for T1N0 cancer versus 89% for T2N0 cancer (P = 0.01). We have prospectively confirmed that a low rate of proliferation as measured by SPF or MIB1 determination confers an excellent prognosis in invasive node-negative breast cancer up to 5 cm in size, regardless of adjuvant treatment.

Molecular pathology of tumor metastasis. I. Predictive pathology

Millennium reviews of oncology agreed that the last century produced major developments mainly in the management of the primary tumor, but despite all of these results, cancer still remains among the leading causes of death due to the failure of clinical management of disseminated disease. This failure is primarily due to the lack of detailed information on the molecular mechanisms of tumor metastasis. Therefore, one of the hottest fields in experimental oncology is metastasis research, which provides more and more information about the molecular mechanisms. However, this information is fragmented and is not yet exploited in clinical practice. A new field of diagnostic pathology recently emerged, which translates basic research data to diagnostic practice to provide clinically relevant information on the biological potential (in this case metastatic potential) of the malignant tumors. Since tumor cell-extracellular matrix interactions are key features of tumor dissemination, expression of genes responsible for them can define the metastatic potential of malignant tumors. This review summarizes our recent knowledge on the metastatic geno- and phenotype of major human solid tumors: lung, colon, breast, prostate cancers and malignant melanoma.

Telomerase activity in melanocytic lesions: A potential marker of tumor biology

Telomerase activation, being a cardinal requirement for immortalization, is a crucial step in the development of malignancy. With a view toward diagnostic and biological aspects in melanocytic neoplasia, we investigated the relative levels of telomerase activity in 72 nevi and 16 malignant melanomas by means of a modified telomeric repeat amplification protocol (TRAP) assay, including an internal amplification standard. We further compared telomerase activity with the expression of two different proliferation-specific proteins, Ki-67 and repp86, a protein expressed exclusively in the cell cycle phases S, G2, and M. Telomerase activity was associated with the overall growth fraction (Ki-67) but showed a closer correlation with the expression of repp86. Both telomerase activity and proliferation indices discriminated clearly between malignant melanomas and nevi, but not between common and dysplastic nevi. Nonetheless, a portion of nevi exhibited markedly elevated telomerase activity levels without proportionally increased proliferation. This was independent of discernible morphological changes. Clinicopathological correlations showed an association between high telomerase activity and early metastatic spread in melanomas, linking telomerase to tumor biology. Our results provide arguments in favor of an occasional progression from nevi to melanomas and imply that proliferation measurements in combination with telomerase assays may help to elicit early malignant transformation that is undetectable by conventional morphology.