Standardized staining and analysis of argyrophilic nucleolar organizer region associated proteins (AgNORs) in radically resected colorectal adenocarcinoma--correlation with tumour stage and long-term survival

The flavonoid chrysin attenuates colorectal pathological remodeling reducing the number and severity of pre-neoplastic lesions in rats exposed to the carcinogen 1,2-dimethylhydrazine

Phenolic compounds are naturally occurring, bioactive substances with marked antioxidant and anti-inflammatory potential. The flavonoid chrysin, found in high levels in honey bee propolis, inhibits the activity of enzymes involved in carcinogenesis. We have investigated the effect of chrysin on pre-neoplastic colorectal lesions (ACF, aberrant crypt foci) in a rat model of chemical carcinogenesis induced by 1,2-dimethylhydrazine (DMH). Female Wistar rats weighing 137.2 ± 24.3 g received weekly one subcutaneous injection of DMH (20 mg/kg) for 10 weeks. The animals were divided into five groups each with seven animals: Group 1, 0.9% saline; Group 2, DMH+0.9% saline; Group 3, DMH+chrysin (10 mg/kg); Group 4, DMH+chrysin (100 mg/kg); Group 5, DMH+chrysin (200 mg/kg). Groups 2 and 3 showed a significant increase in ACF number, nucleolus organizer regions per enterocyte nucleus and nitrite/nitrate serum levels compared with Group 1. Groups 4 and 5 presented a significant reduction in all these parameters compared with Group 2. The levels of antioxidant minerals (copper, magnesium, selenium, zinc) and the number of enteroendocrine and mucin-producing cells were significantly reduced in Groups 2 and 3 but were similar in Groups 4 and 5 compared with Group 1. Chrysin, at 100 mg/kg and 200 mg/kg, was effective in attenuating pathological colorectal remodeling, reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects might be attributable to the recovery of antioxidant mineral levels, a reduction in systemic nitrosative stress and an inhibition of the cellular proliferation induced by this flavonoid.

Staging and survival of rectal cancer in Vila Nova de Gaia, Portugal

INTRODUCTION

In the county of Vila Nova de Gaia (northern Portugal) in the period of 2004-2006, there were an average of 35 new cases of colorectal cancer per 100,000 population, which constitutes one of the highest rates in the world. The latest research has shown that there are many differences between colon and rectal cancers, thereby justifying an independent approach.

PATIENTS AND METHODS

The study pertained to the period 1995-2004, by using the census of 1991 and 2001 for calculating specific rates. The 399 diagnosed cases of rectal cancer were drawn from a specialized and active cancer registry, oncological registry of Gaia. Overall survival was calculated using the Kaplan-Meier method and the curves were compared using a Log Rank test. The effect of topography and histological type on survival was obtained by controlling the stage disease, using a Cox proportional hazards regression model.

RESULTS

There was a slight predominance of males, with a ratio between sexes of 1 : 3. The 50% overall survival rate after 5 years increased over time. The localization of the tumour and the histological type, after adjusting by stage, were not significant factors in the prognosis.

CONCLUSION

Our study shows an increase in the number of cases over time, particularly in elderly women. The cumulative risk of having rectal cancer remains unchanged from 1981 to 2004. Unlike other studies, an increase in early lesions was not observed.

Nucleolar Organizer Regions as a Prognostic Indicator in Epithelial Cancers of the Ovary

Recent studies have shown that quantification of silver-stained nucleolar organizer region associated proteins (AgNORs) is correlated with ploidy and proliferative activity in several neoplasms. The prognostic value of this marker, however, has not been well defined in epithelial ovarian carcinomas (EOCs). We studied 84 cases of EOCs in an attempt to assess the potential prognostic significance of AgNORs and to compare the results with other prognostic factors in EOCs. Clinical, operative and treatment details, and follow-up data were recorded for each case. In univariate analysis, a highly significant correlation of AgNOR count with clinical stage (p < 0.01), histologic grade (p < 0.05), response to chemotherapy (p < 0.05), and biologic behavior (p < 0.01) was found. High AgNOR counts were observed in late stage (III and IV) tumors, grade 3 carcinomas, tumors in patients with partial response to chemotherapy, progressive disease, recurrence, or death from tumor. In multivariate analysis, AgNOR count at cut off 3.5 was found to be the third prognostic variable after response to therapy and stage. These observations suggest that AgNOR count holds promise for prediction of tumor aggressiveness in EOCs. However, its role as an independent prognostic variable of patient survival remains questionable.

Proliferative activity is the most significant predictor of recurrence in noninvasive papillary urothelial neoplasms of low malignant potential and grade 1 papillary carcinomas of the bladder

BACKGROUND

Recurrence of transitional cell carcinoma of the bladder cannot be predicted accurately by traditional criteria alone. This study examined the value of cell proliferative activity, morphometry, and expression of p53, c-erbB-2, and bcl-2 oncogenes in predicting recurrence of superficial papillary urothelial neoplasms of low malignant potential (LMP) and Grade 1 (G1) papillary carcinomas of the bladder.

METHODS

Sixty-two patients (mean age, 62 years) with newly diagnosed superficial pTa bladder tumors (19 LMP, and 43 G1) were analyzed retrospectively. All patients underwent transurethral resection (TUR). Median follow-up was 69 months. Serial sections from formalin-fixed, paraffin-embedded material at initial TUR were stained with monoclonal antibodies (MoAbs) DO7, CB11, and bcl-2-124. Cell proliferation was assessed by MIB-1 MoAb, the quantity of argyrophilic nucleolar organizer region-associated proteins (AgNORs), and mitotic count.

RESULTS

Of the 62 patients, 42 (67.7%) had one or more recurrences. Recurrence rates were higher in MIB-1 (P < 0.0001) and p53 immunopositive cases (P = 0.02), when the mitotic count was greater than 5 (P = 0.004), and in G1 carcinomas (P = 0.04). In univariate analysis, the disease-free period was shorter for MIB-1 (P < 0.0001) and p53 immunopositive (P = 0.0001) cases, for cases with high AgNOR quantity (P = 0.04), mitotic count greater than 5 (P = 0.01), and in G1 carcinomas (P = 0.002). In multivariate analysis, only MIB-1 immunoreactivity retained independent prognostic significance.

CONCLUSIONS

Despite the small cohort, the results confirm the prognostic value of cell proliferation and p53 expression in patients with bladder neoplasms. The results also indicate that MIB-1 immunopositivity is the most significant predictor of recurrence and disease-free survival in superficial LMP and G1 papillary bladder carcinomas.

Standardized AgNOR analysis in actinic keratosis

To assess if the quantity of silver-stained nucleolar organizer region (AgNOR) proteins predicts the behavior of actinic keratosis (AK), we performed a standardized AgNOR analysis on 51 cases of AK; in addition, 10 cases of squamous cell (SCC) and 10 cases of basal cell (BCC) carcinomas and 10 normal skin samples were also studied. AgNOR analysis was performed on formalin-fixed and paraffin-embedded sections according to the guidelines of the Committee on AgNOR Quantification (1995), evaluating the mean area (microm(2)) of AgNORs per nucleus (NORA). A highly significant P value (< 0.001) was found in the comparison among NORA values of normal skin (1.869 microm(2); SD + 0.332), AK (3.988 microm(2); SD + 0.914), BCC (3.044 microm(2); SD + 0.254), and SCC (5.286 microm(2); SD + 0.920). In AK, a progressive increase of mean NORA values was observed moving from Stage I (3.161 microm(2); SD + 0.600) to Stage II (3.455 microm(2); SD + 0.562), Stage III (4.360 microm(2); SD + 0.295), and Stage IV (5.168 microm(2); SD + 0.694); highly significant differences (P < 0.001) were noted when Stages I or II were compared with Stage III or Stage IV or between these latter stages. The AgNOR quantity may identify AKs with high proliferative activity and increased tendency to develop into invasive SCC.

[AgNOR in stomach neoplasm]

OBJECTIVE

To study the proliferative activity of AgNORs (argyropholic nucleolar organizer region) in gastric cancer tissue and in the adjacent normal tissue and correlate with the clinical and pathological parameters.

MATERIAL AND METHODS

Thirty four formalin-fixed paraffin-embedded tissues sections of patients with adenocarcinoma of the stomach were analysed retrospectively, being 23 of intestinal and 11 of diffuse type of Lauren. The AgNORs can be detected by a specific silver staining and the number de AgNORs was counted in 100 nucleus of tumoral cells and in 100 nucleus of the adjacent normal tissue.

RESULTS

The tumoral cells had numerous, smaller, aggregated or one solitary and bigger AgNORs in the nuclei, while the normal cells had one or two AgNORs by nuclei. A significant difference was found between the mean numbers of AgNORs in the nuclei of tumor (3.86) and the normal tissue (1.25). There was also a significant difference between intestinal (4.43) and diffuse type (2.58) means. No significant correlation was found between mean AgNOR count and sex or age of the patients.

CONCLUSIONS

The quantification of AgNORs can be used as a marker of proliferative activity, helping on the diagnosis of cancer.

Significance of Wet Autoclave Pretreatment in Immunohistochemistry

Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced in routine diagnostic immunohistochemistry for the detection of estrogen- and progesterone receptors, L26-, Ki-67- and bcl-2 antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar organizer regions- associated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric study group as the standardized method for AgNOR analysis in archival material.

Correlation between silver-stained nucleolar organizer region area and cell cycle time

BACKGROUND

The relationship between the population doubling time and the quantity of silver-stained nucleolar organizer region (AgNOR) interphase proteins was studied in cell culture at three different temperatures used to modulate the cell cycle duration.

METHODS

After MIB 1 and AgNOR combined staining, the quantity of AgNOR proteins was measured in cycling cells by image cytometry.

RESULTS

Among the several parameters calculated, the AgNOR relative area showed a strong correlation with the changes of the population doubling time induced by different temperatures.

CONCLUSIONS

The results support the hypothesis that the cell cycle time and the size of the ribogenesis machinery are coregulated and that measurements of AgNORs can thus be used as a static evaluation of the cell cycle duration in arbitrary units.

Proliferative Activity of Epidermal Basal Cells after Wounding

Quantitative changes in nucleolus organizer regions (NORs) are known markers of proliferation that can be demonstrated by a specific silver staining technique on paraffin-embedded sections. Wounding of skin induces proliferation of basal epidermal cells at the wound margin. The degree of proliferation depends on the survival time and can be measured by morphometric assessment of argyrophilic NORs (AgNORs). Following incision wounding of the pinnae, rats were allowed to survive for different intervals (7 rats per interval) up to 120 hours. Before each sacrifice, biopsies were taken and incubated in a bromodeoxyuridine (BrdU) solution, embedded in paraffin, and stained with an antibody against BrdU. At the same time morphometric analysis of AgNOR counts was performed on sections made from the same material. BrdU incorporating nuclei were assessed by simple counting, whereas morphometric analysis of AgNOR counts was computer aided. Both methods revealed an increase in the number of proliferating cells, a plateau phase being reached after about 36 hours, followed by a decline after about 70 hours. Both methods thus allowed a reliable temporal classification of the skin injury according to survival time. The molecular background of the AgNOR changes in relation to the proliferation of cellular elements is discussed in detail.

Nuclear morphometry in male breast carcinoma: association with cell proliferative activity, oncogene expression, DNA content and prognosis

To investigate the prognostic value of nuclear morphometry in male breast carcinoma (MBC), histological samples from 50 patients (mean age 62.2 years) were retrospectively analyzed by computerized nuclear morphometry. All patients received surgery; 35 had multiple combinations of adjuvant therapies. Mean follow-up was 67 months (range 1-230). In each case, 100 tumor cells were measured, and the mean nuclear area (MNA), standard deviation of the nuclear area (SDNA), mean nuclear perimeter (MNP), standard deviation of the nuclear perimeter (SDNP) and shape factor (SHF) were calculated. Morphometric features were compared with tumor histological grade, size, nodal status, DNA ploidy evaluated by flow-cytometry and cell proliferative activity assessed by the quantity of argyrophilic nucleolar organizer region-associated proteins (AgNORs), monoclonal antibody (MAb) PC10 against proliferating cell nuclear antigen and MAb MIB-1. Comparison was also made with the immunohistochemical detection of p53, bcl-2, c-erbB-2 and c-myc proteins. Significant association was found between nuclear morphometric parameters and tumor grade, DNA content and cell proliferation indices. SDNA was greater in p53-positive and bcl-2-negative cases; SDNP was greater in p53-positive cases; SHF was lower in p53- and c-myc-positive cases. Overall survival was shorter in carcinomas with high MNA, SDNA, MNP and SDNP and low SHF. In multivariate analysis, performed by testing nuclear morphometric parameters, histological grade, tumor size, nodal status and p53 immunostaining in the Cox model, p53 over-expression and histological grade retained independent prognostic significance. When p53 was excluded, only SDNP appeared as an independent prognostic variable. Our results indicate that nuclear morphometric parameters can identify an aggressive tumor phenotype and provide additional prognostic information for patients with MBC.

Prognostic factors in colorectal cancer. College of American Pathologists Consensus Statement 1999

BACKGROUND

Under the auspices of the College of American Pathologists, the current state of knowledge regarding pathologic prognostic factors (factors linked to outcome) and predictive factors (factors predicting response to therapy) in colorectal carcinoma was evaluated. A multidisciplinary group of clinical (including the disciplines of medical oncology, surgical oncology, and radiation oncology), pathologic, and statistical experts in colorectal cancer reviewed all relevant medical literature and stratified the reported prognostic factors into categories that reflected the strength of the published evidence demonstrating their prognostic value. Accordingly, the following categories of prognostic factors were defined. Category I includes factors definitively proven to be of prognostic import based on evidence from multiple statistically robust published trials and generally used in patient management. Category IIA includes factors extensively studied biologically and/or clinically and repeatedly shown to have prognostic value for outcome and/or predictive value for therapy that is of sufficient import to be included in the pathology report but that remains to be validated in statistically robust studies. Category IIB includes factors shown to be promising in multiple studies but lacking sufficient data for inclusion in category I or IIA. Category III includes factors not yet sufficiently studied to determine their prognostic value. Category IV includes factors well studied and shown to have no prognostic significance.

MATERIALS AND METHODS

The medical literature was critically reviewed, and the analysis revealed specific points of variability in approach that prevented direct comparisons among published studies and compromised the quality of the collective data. Categories of variability recognized included the following: (1) methods of analysis, (2) interpretation of findings, (3) reporting of data, and (4) statistical evaluation. Additional points of variability within these categories were defined from the collective experience of the group. Reasons for the assignment of an individual prognostic factor to category I, II, III, or IV (categories defined by the level of scientific validation) were outlined with reference to the specific types of variability associated with the supportive data. For each factor and category of variability related to that factor, detailed recommendations for improvement were made. The recommendations were based on the following aims: (1) to increase the uniformity and completeness of pathologic evaluation of tumor specimens, (2) to enhance the quality of the data needed for definitive evaluation of the prognostic value of individual prognostic factors, and (3) ultimately, to improve patient care.

RESULTS AND CONCLUSIONS

Factors that were determined to merit inclusion in category I were as follows: the local extent of tumor assessed pathologically (the pT category of the TNM staging system of the American Joint Committee on Cancer and the Union Internationale Contre le Cancer [AJCC/UICC]); regional lymph node metastasis (the pN category of the TNM staging system); blood or lymphatic vessel invasion; residual tumor following surgery with curative intent (the R classification of the AJCC/UICC staging system), especially as it relates to positive surgical margins; and preoperative elevation of carcinoembryonic antigen elevation (a factor established by laboratory medicine methods rather than anatomic pathology). Factors in category IIA included the following: tumor grade, radial margin status (for resection specimens with nonperitonealized surfaces), and residual tumor in the resection specimen following neoadjuvant therapy (the ypTNM category of the TNM staging system of the AJCC/UICC). (ABSTRACT TRUNCATED)

Nucleolar size indicates the rapidity of cell proliferation in cancer tissues

In order to define the importance of the nucleolus in tumour pathology, the relationship between nucleolar size and function and tumour mass growth rate was studied in vivo. Ten established human cancer cell lines from colon carcinomas and neuroblastomas were inoculated subcutaneously in athymic mice and the doubling time (DT) of the xenograft tumour mass was calculated. The tumour DTs ranged from 3.2 to 15.7 days. Nucleolar size was evaluated in sections from formalin-fixed and paraffin-embedded tumour samples after silver staining for AgNOR proteins, using a specific image analysis system. The nucleolar area values were inversely related to the xenograft tumour mass DTs (r=-0.90; p<0.001). Nucleolar functional activity was also evaluated using rapid, intermediate, and slow growing tumours (one each). The values of RNA polymerase I activity measured in vitro were strongly related to the corresponding tumour DTs (r=-0. 99; p=0.03). The labelling indices (LIs) of three proliferation markers, MIB1, PCNA, and bromodeoxyuridine (BrdU), were also evaluated. As revealed by the MIB1 and PCNA LIs, almost all the cells of the xenograft tumours were cycling (86.6+/-5.6 SD and 95. 5+/-2.0 SD, respectively). Neither the MIB1, PCNA or BrdU LIs were related to the xenograft tumour mass DT, showing that the different growth rates of tumour xenografts were not due to different growth fractions, but were mainly related to different cell proliferation rates. The present data demonstrate that the size and function of the nucleolus are related to the cell proliferation rate of cancer tissue. Evaluation of nucleolar size after silver staining of AgNOR proteins represents a unique parameter for the histological assessment of rapidity of cell proliferation in tumour lesions.

Colorectal cancer staging and adjuvant chemotherapy

Colorectal cancer is a significant cause of morbidity and mortality in Western populations. The standard of care for staging patients with colorectal cancer to determine prognosis and identify patients who will receive adjuvant therapy continues to be histopathology of regional lymph nodes. However, the significant variability in survival within each staging category likely reflects the heterogeneity of detecting micrometastatic disease employing this technique. Novel molecular markers of micrometastases currently in development will permit more accurate staging of patients with colorectal cancer. These advances in staging will distinguish patients who will maximally benefit from adjuvant therapy from those who have an especially good prognosis in whom chemotherapy can be avoided. In addition, new adjuvant chemotherapeutic agents, novel combinations of those agents and creative dosing schedules currently being investigated will offer considerable advantages with respect to ease of administration, safety and tolerability, quality of life and efficacy. Ultimately, it is anticipated that advances in molecular diagnostics will define unique biochemical characteristics of patients' tumours, permitting individualization of chemotherapeutic regimens employing novel agents that specifically exploit those characteristics.

American Joint Committee on Cancer Prognostic Factors Consensus Conference: Colorectal Working Group

BACKGROUND

The American Joint Committee on Cancer (AJCC), which regularly reviews TNM staging systems, established a working party to develop recommendations for colorectal carcinoma.

METHODS

A multidisciplinary consensus conference using published literature developed an arbitrary classification system of prognostic marker value (Category I, IIA, IIB, III, and IV), which forms the framework for this report.

RESULTS

The working party concluded that several T categories should be subdivided: pTis into intraepithelial carcinoma (pTie) and intramucosal carcinoma (pTim); pT1 into pT1a and pT1b corresponding to the absence or presence of blood or lymphatic vessel invasion, respectively; and pT4 into pT4a and pT4b according to the absence or presence of tumor involving the surface of the specimen, respectively. The working party also recommended that TNM groups be stratified based on the presence or absence of elevated serum levels of carcinoembryonic antigen (CEA) (>/= 5 ng/mL) on preoperative clinical examination. In addition, the working party also concluded that carcinoma of the appendix should be excluded from the colorectal carcinoma staging system because of fundamental differences in natural history.

CONCLUSIONS

The TNM categories and stage groupings for colorectal carcinoma published in the current AJCC manual have clinical and academic value. However, a few categories require subdivision to provide increasing discrimination for individual patients. The serum marker CEA should be added to the staging system, whereas multiple other factors should be recorded as part of good clinical practice. Although many molecular and oncogenic markers show promise to supplement or modify the current staging systems eventually, to the authors' knowledge none have yet been evaluated sufficiently to recommend their inclusion in the TNM system.

AgNOR staining and quantification

Nucleolar organiser regions (NORs) are defined as nucleolar components containing a set of argyrophilic proteins, which are selectively stained by silver methods. After silver-staining, the NORs can be easily identified as black dots exclusively localised throughout the nucleolar area, and are called "AgNORs". The NORs' argyrophilia is due to a group of nucleolar proteins, which have a high affinity for silver (AgNOR proteins). A number of studies carried out in different tumour types demonstrated that malignant cells frequently present a greater AgNOR protein amount than corresponding non-malignant cells. Moreover, in cancer tissues AgNOR protein expression was found to be strictly related to the cell duplication rate. Over the past 12 years, the "AgNOR method" has been applied in tumour pathology for both diagnostic and prognostic purposes. However, the lack of a standardised silver-staining protocol has led to much misinterpretation of actual structures evaluated in individual studies. Indeed, the absolute AgNOR scores reported by different authors for the same types of tumour are scarcely comparable and the results produced by these investigations sometimes seem to be conflicting. In order to achieve definitive standardisation of the AgNOR method and produce comparable data in all laboratories, the "International Committee on AgNOR Quantitation" was founded, and during the first Workshop "AgNORs in Oncology" held in Berlin in 1993 guidelines for AgNOR protein evaluation were first defined. The present paper discusses the main technical aspects of NOR silver-staining, and critically evaluates the methods commonly employed for AgNOR protein quantification in routine cyto-histopathology.

Prognostic relevance of AgNORs in tumor pathology

The importance of the analysis of the silver-stained nucleolar organizer regions (AgNORs) for prognostic purposes in tumor pathology has been reviewed. Current available data from the literature demonstrate that the evaluation of the quantity of interphase AgNORs is an independent prognostic factor in several types of human tumors. Results of our investigations indicate that AgNORs are the most powerful variable predicting survival in patients with pharyngeal carcinoma, multiple myeloma, male breast and prostate carcinoma. The combination of AgNOR counts and histologic pattern allows the stratification of patients with multiple myeloma, pharyngeal and prostate carcinoma into low- and high-risk groups, which could benefit from different therapy. Moreover, AgNOR analysis predicts response to treatment in adult patients with acute myelogenous leukemia, and appears as an independent prognostic factor in a prospective study on renal cell carcinoma. Therefore, AgNOR analysis is a really important prognostic factor for several human neoplasias. The experimental and theoretical justifications for AgNORs as a prognostic factor are also reviewed, in particular the strict correlation between AgNOR quantity and tumor cell doubling time. Lastly, the lack of prognostic significance of AgNOR analysis in some circumstances is critically discussed.

In situ standardised AgNOR analysis: a simplified method for routine use to determine prognosis and chemotherapy efficiency in colorectal adenocarcinoma

Standardised AgNOR analysis as recommended by the Committee on AgNOR Quantitation of the European Society of Pathology is now regarded as the gold standard, particularly when retrospective studies on archival, formalin-fixed, and paraffin-embedded material are performed. This article deals with the implementation of the standardised AgNOR method in colorectal carcinoma and its consequent impact on clinical decision making. First, the clinical relevance of AgNOR analysis as a major and independent prognostic factor in exclusively surgically treated adenocarcinomas of the colon and rectum is elucidated. Additionally, due to the fact that in last 10 years 5-Fluorouracil based chemotherapy and radiotherapy have become standard treatment in a variety of tumour stages, the outstanding predictive power of AgNOR analysis with regard to chemotherapy efficiency is emphasised.

Standardized in situ AgNOR analysis in breast pathology: diagnostic and cell kinetic implications

The aim of the present study was to assess the diagnostic value of the recently standardized morphometric analysis of silver-stained nucleolar organizer region-associated proteins (AgNORs) [30] in a variety of 155 routinely processed benign and malignant breast lesions. 5 normal breast samples, 21 adenoses, 20 ductal hyperplasias, 10 atypical ductal hyperplasias, 20 in situ and 43 invasive ductal carcinomas, 10 in situ and 26 invasive lobular carcinomas were investigated. A statistically highly significant difference was found between normal/ordinary hyperplastic and neoplastic breast lesions with all 4 consensus AgNOR parameters (mean area, mean number, CV of area, CV of number) evaluated. AgNOR quantity was significantly related to histological grade of both in situ and invasive carcinomas. However, variable overlap was found between AgNOR values in different diagnostic groups. We conclude that standardized AgNOR analysis is a prerequisite for objective and reproductible AgNOR assessment in archival tissues. Despite its limited diagnostic utility for individual breast lesions, standardized AgNOR analysis bears a significant potential for characterizing cell kinetic and metabolical activity of breast lesions. This may give insight into the biological background of breast carcinogenesis, differentiation and tumor progression and may also underlie the independent prognostic value of AgNORs in breast cancer.

Proliferation of hepatic metastases of colorectal carcinoma: relationship to primary tumours and prognosis after hepatic resection

In this study, we determined the proliferation indices of liver metastatic tumours originating from colorectal carcinomas using Ki67 and argyrophil nucleolar organizer region associated proteins (AgNOR) stain. We examined the primary and metastatic tumours in 27 patients with liver metastasis and eight cases with non-metastatic colorectal carcinoma as a control.The number of AgNOR dots in metastatic tumours was significantly higher than in the respective primary tumours of the metastasis group or in non-metastatic colorectal carcinomas. The Ki67 labelling index was similar in all groups. The Ki67 labelling index and AgNOR counts did not correlate with each other. There was no significant relationship between proliferation indices and the duration of the disease-free period following hepatic resection for metastases or with prognosis after hepatectomy. We conclude that Ki67 and AgNOR are not useful indicators of prognosis in patients who undergo operation for liver metastasis of colorectal carcinomas.

Silver-stained nucleolar organizer regions in hypertrophic and keloid scars

Silver-stained nucleolar organizer regions (AgNORs) have been widely used as a marker of cellular activity and proliferation. In a retrospective study, we investigated the potential value of AgNORs in 12 hypertrophic and 24 keloid scar tissues. Ten normal skin tissues served as controls. A standard silver-staining method was used, and the mean AgNOR count of dermal fibroblastic cells in each tissue was determined. In normal skin, the mean AgNOR count of dermal fibroblasts was 1.79+/-0.55, whereas fibroblastic cells in hypertrophic and keloid scars had mean AgNOR counts of 3.18+/-0.56 and 5.10+/-0.97, respectively. There was a statistically significant difference between the mean AgNOR counts of fibroblastic cells from normal skin, hypertrophic scar, and keloid scar [one-factor analysis of variance (ANOVA), p < 0.0001]. Our findings suggest that AgNOR count may be a useful marker for assessment of fibroblastic cell activity in hypertrophic and keloid scars, which may have potential value for histologic and biologic characterization of the two lesions.

Standardized AgNOR analysis of the invasive tumour front in oral squamous cell carcinomas

In the last decade, silver staining of nucleolar organizer region-associated proteins (AgNORs) has been widely used in tumour pathology both for diagnostic and for prognostic purposes. However, a reliable and reproducible assessment of these proteins on routinely processed archival tissues has only become possible since the recent introduction of standardized staining method and computer-aided morphometric analysis. In the present study, the AgNOR content at the invasive front of 80 squamous cell carcinomas of the floor of the mouth/tongue was investigated using this novel approach, with regard to prognosis and a variety of clinico-pathological parameters. All standardized AgNOR parameters [mean of AgNOR number, mean of AgNOR area, coefficients of variation (CV) of both AgNOR number and area] were statistically significantly associated with the clinical course. The strongest correlation was found for the AgNOR-area univariate analysis (P = 0.006). In multivariate analysis, the mean of AgNOR number could independently predict both overall (P = 0.01) and disease-free survival (P = 0.001). It is concluded that standardized staining and computer-aided analysis of AgNORs are prerequisites for an objective and reproducible AgNOR assessment, which has potential as a supplementary diagnostic and prognostic tool in oral cancer.

High and low risk prostate carcinoma determined by histologic grade and proliferative activity

BACKGROUND

Histologic grade of differentiation is a strong prognostic factor for prostate carcinoma. However, most tumors fall in the intermediate group. Nuclear and nucleolar morphometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) were performed to improve prognosis, especially for patients with intermediate histologic grade tumors.

METHODS

Core needle biopsies from 65 patients with primary prostate carcinoma at diagnosis were studied. Patients received only hormone therapy. Formalin fixed and paraffin embedded sections were stained with the method of Ploton. The mean AgNOR count was calculated in 100 tumor cells for each case. Nuclear and nucleolar areas from 100 cells were measured with an automated image analyzer. One-way analysis of variance and uni- and multivariate survival analyses were used for statistical evaluation.

RESULTS

In the whole series, World Health Organization (WHO) tumor grade, nuclear and nucleolar areas, and AgNOR counts were correlated with survival time. By multivariate analysis, only AgNOR counts retained independent prognostic significance. In WHO Grade 2 carcinoma, the 5-year survival rate for patients with AgNOR/cell < or = 7.84 was 77%, but was only 12% for those with higher counts (P < 0.0001). These survival rates were similar to those obtained when patients with WHO Grade 1 carcinoma and Grade 2 carcinoma plus low AgNOR counts were compared with patients with Grade 3 carcinoma and Grade 2 carcinoma plus high AgNOR counts. In Gleason intermediate Grade 6 and 7 carcinomas, the 5-year survival rate for patients with AgNOR/cell < or = 7.84 was 71%, but was only 7% for those having higher counts (P = 0.0001).

CONCLUSIONS

Nuclear and nucleolar areas, as well as AgNOR counts, supplement histologic grading in the prognostic assessment of prostate carcinoma in patients receiving only hormone therapy. AgNOR count also is a prognostic factor for patients with intermediate grade tumors. The combination of histologic grade and proliferative activity allows the stratification of patients into low and high risk groups.

Prognostic value of histobiological factors (malignancy grading and AgNOR content) assessed at the invasive tumour front of oral squamous cell carcinomas

Tumour cells at the invasive front of carcinomas have been found to differ substantially from the rest of tumour cells in a variety of human cancers. The present multivariate survival analysis of 94 oral squamous cell carcinomas (OSCCs) revealed that both the argyrophilic nucleolar organizer regions-associated protein (AgNOR) content of invading tumour cells and a multiparametric histopathological tumour front grade were significantly and independently associated with tumour-related death, irrespective of conventional Broders' grade and clinical stage of the tumours. High tumour front scores and AgNOR content at the invasive OSCC front thus seem to reflect increased malignant potential. Proliferative activity, assessed by standardized AgNOR analysis, most probably represents one of the biological features underlying the usefulness of evaluating the invasive tumour front.

Predictive value of argyrophilic nucleolar-organizer-region-associated proteins in bladder cancer, using cell-imprint preparations

The predictive value of quantifying argyrophilic nucleolar-organizer-region-associated proteins (Ag-NOR) in routinely processed paraffin-embedded tissue sections of bladder cancer remains controversial. The purpose of this study was to determine whether cell-imprint preparations facilitate a more accurate determination of the mean number of Ag-NOR per cell (Ag-NOR score). The utility of using the Ag-NOR scores of cell-imprint preparations as a prognostic indicator in patients with bladder cancer was explored. We evaluated 90 patients with newly diagnosed bladder cancer using cell-imprint preparations to determine Ag-NOR score. The score significantly correlated with known prognostic factors associated with this tumor, including histological grade (P < 0.001), pathological stage (P < 0.01), and papillary structure (P < 0.001). Furthermore, the Ag-NOR score appeared to be an independent predictor of intravesical tumor recurrence of superficial bladder cancer (P < 0.05). These results suggest that the Ag-NOR score determined in a cell imprint preparation may serve as a useful prognostic indicator in bladder cancer.

Standardized AgNOR analysis: its usefulness in surgical oncology

Recent improvements both in the staining quality and computer-aided quantitation of silver-stained nucleolar organizer region (AgNOR)-associated proteins offer the possibility to reliably investigate these proteins on routinely processed archival material. This article deals with the historical background, the recent introduction of a standardized quantitation, the clinical relevance, and future perspective for AgNOR evaluation. It is specifically emphasized that AgNOR analysis after both standardized staining and computer-aided quantitation (as recommended by the Committee on AgNOR Quantitation of the European Society of Pathology) is now regarded as the gold standard whenever routinely formalin-fixed and paraffin-embedded material is investigated.