Argyrophilic nucleolar organiser region counts and prognosis in pharyngeal carcinoma

Biological Predictors of Response to Radiotherapy in Head and Neck Cancer: Recent Advances and Emerging Perspectives

The study of new biological parameters has received considerable attention in radiotherapy during the last decade due to their potential value in predicting treatment response in squamous cell carcinoma of the head and neck (SCC-HN) and the foreseen possibility of selecting altered fractionation radiotherapy for the individual patient. Although there are established clinical parameters in SCC-HN patients that relate to radiation response (extent of disease, hemoglobin level), recent advances with direct measurement of tumor oxygenation, inherent radiosensitivity and proliferation rate have increased the promise of individualization of treatment strategy according to these radiobiologically based parameters. Molecular research has now identified a host of new biological parameters with potential predictive utility; oncogenes, tumor suppressor genes, cell-cycle control genes, apoptosis genes and angiogenesis genes have been extensively studied and correlated with radiation response. Moreover, study of the epidermal growth factor receptor signal-transduction system as a possible response modulator has recently fostered molecular strategies which employ blockade of the receptor to down-regulate tumor growth. This article briefly reviews and analyzes the main controversial issues and drawbacks that hinder the general use of biological parameters for predicting tumor response to radiotherapy. It highlights the future perspectives of radiotherapy predictive assay research and the need to shift from single-parameter analysis to multiparametric studies which take into account several potential predictors that together are involved in different biological and clinical pathways.

Prognostic relevance of cell proliferation in head and neck tumors

Cell proliferative activity has been extensively investigated in head and neck tumors. Ki67/MIB-1 immunostaining, tritiated thymidine or bromodeoxyuridine labeling indices, DNA S-phase fraction, proliferating cell nuclear antigen expression, potential doubling time and analysis of the nucleolar organizer region associated proteins (AgNORs) have shown significant correlation with prognosis in 4806 cases of tumors of the oral cavity, salivary glands, pharynx and larynx. However, this was not observed in 2968 other reported cases. Discrepancies may depend on various factors: the heterogeneity of the series, which include tumors from various anatomic sites and patients treated with different therapy, and the lack of standardization of methods for assessing cell proliferation. Furthermore, none of the methods currently applied can by themselves define the actual proliferative activity, as it depends both on the proportion of cells committed to the cycle (growth fraction) and the speed of the cell cycle. Indeed, the actual proliferative activity of a tumor could well be measured by the equation [PA = Ki67 or MIB-1 scores x AgNORs], as we did in pharyngeal carcinoma. Provided that large and homogeneous series are evaluated by standardized methods, cell proliferative activity can still be regarded as an inexpensive and reliable prognostic factor in head and neck tumors.

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.

PCNA/AgNOR and Ki-67/AgNOR double staining in oral squamous cell carcinoma

This study was performed on oral squamous cell carcinomas (OSCC) in order to investigate the relation between the number of interphase silver-stained nucleolar organizer regions (AgNORs) and the immunolabeling of proliferation-associated markers, using antibodies to Ki-67 and proliferating cell nuclear antigen (PCNA). Fifteen consecutive cases of oral squamous cell carcinoma were used and a double staining technique was performed in order to quantify the number of NORs in PCNA-positive and -negative cells as well as in Ki-67-positive and -negative cells. Our results showed a higher mean number of AgNORs in PCNA- and Ki-67-positive cells than in PCNA- and Ki-67-negative cells. We concluded that there is an association between cell proliferation and AgNOR score in OSCC.

Bax expression has prognostic significance that is enhanced when combined with AgNOR counts in glottic carcinomas

Using nucleolar organizer regions (NORs) as a proliferative marker and Bax expression as a marker for apoptosis, we have studied the individual and combined prognostic significance of these markers. Successive sections of diagnostic, formalin-fixed and paraffin-embedded specimens from 69 patients with T1-4 tumours were stained with a rabbit anti-human Bax polyclonal antibody and silver nitrate for visualization of NORs (AgNORs). After classification for staining intensity and the percentage of Bax expression, a final score resulting in four classes of increasing Bax expression was obtained. AgNOR counts were expressed as mean counts (mAgNOR) and the percentage of tumour nuclei with more than one AgNOR (pAgNOR>1). Both AgNOR parameters were grouped in three classes with increasing values. Low Bax scores correlated significantly with poor prognosis (P = 0.0106). For mAgNOR and pAgNOR>1, high values correlated with poor prognosis (P = 0.0185 and P = 0.0003 respectively). A combined parameter, for which the Bax score was subtracted from the AgNOR scores, appeared to be statistically stronger than the individual parameters (P < 0.0001). Both Bax expression and AgNOR scores, and in particular the combination of these parameters, appear to be strong prognostic markers in glottic squamous cell carcinomas.

Nucleolar organizer regions and prognosis in glottic squamous cell carcinoma

BACKGROUND

The quantity of nucleolar organizer regions (AgNORs) appear to be prognostic significant in several tumor types.

METHODS

Sections from 93 routinely processed pretreatment biopsies from patients with glottic carcinomas were stained by silver nitrate and evaluated by two counting methods: (1) the mean number of AgNOR per tumor nucleus (mAgNOR), and (2) the number of tumor nuclei with one, two, three, four, and more than four AgNOR grains. From these figures the percentage of nuclei with one, two or less, three or less, and four or less AgNORs (pAgNOR1, aAgNOR < or = 2 etc) were calculated.

RESULTS

The median mAgNOR was 4.3, and low counts correlated favorably with the disease-free period (p = 0.0433). The median percentages for pAgNORs were 14, 26, 38, and 51 for pAgNor1, PAgNOR < or = 2, pAgNor < or = 3 and pAgNOR, < or = 4 respectively. Values above the medians correlated positively with the disease-free period (p-values ranging from 0.0005 to 0.0001). Although pAgNOR < or = 3 appeared to be the best discriminator by multivariate analysis, pAgNOR1 is the method of choice because this parameter is the easiest and quickest to perform.

CONCLUSION

pAgNOR counts appear to be a potent prognostic marker and may become useful in treatment decisions.

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.

DNA ploidy and p53 expression correlate with survival and cell proliferative activity in male breast carcinoma

DNA flow cytometry and the monoclonal antibody DO7 were applied in formalin-fixed, paraffin-embedded specimens from 34 primary male breast carcinomas to verify whether DNA ploidy and p53 expression were associated with survival and proliferative activity. They were compared with tumor clinicopathologic features, sex steroid hormone receptors and cell proliferative activity, assessed by the counts of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody PC10 against the proliferating cell nuclear antigen and the monoclonal antibody MIB-1. A significant correlation was found between survival and tumor ploidy (median survival, 77 months for diploid but only 38 months for aneuploid cases; P = .03) and p53 expression (median survival, 95 months for cases with p53 scores < or = 14.06% versus 33 for cases with P53 scores > 14.06%; P = .0004; median survival, 99 months for p53 negative vs 39 for positive cases; P = .007). Tumor histological grade (P = .006), AgNOR counts (P = .0001), PC10 scores (P = .002), and MIB-1 scores (P = .001) were also associated with prognosis. In the multivariate analysis, only p53 scores (P = .001) or p53 immunopositivity (P = .003) and AgNOR counts (P = .022) retained an independent prognostic significance. Aneuploid tumors had higher AgNOR counts (P = .002), PC10 (P = .007), MIB-1 (P = .006), and p53 scores (P = .01) than diploid cases. A linear relationship was observed between p53 scores and AgNOR counts (r = .41; P = .014), PC10 (r = .46; P = .005), and MIB-1 scores (r = .44; P = .011). These results indicate that DNA ploidy and p53 expression are associated with survival and cell proliferative activity in male breast carcinoma. Quantitative parameters, such as DNA ploidy, p53 scores, AgNOR counts, PC10, and MIB-1 scores substantially improve the prognostic significance of the traditional parameters in male breast carcinoma.

Argyrophilic nucleolar organizer region counts predict survival in thymoma

BACKGROUND

The prognosis of thymoma is related mainly to the tumor stage. The prognostic value of argyrophilic nucleolar organizer regions (AgNORs) has been demonstrated in several human neoplasias. Ninety primary thymomas were investigated retrospectively to assess whether AgNOR analysis could offer additional prognostic information.

METHODS

Sections from surgically resected thymomas, routinely fixed in formol and embedded in paraffin, were stained with the argyrophilic method of Ploton. The mean number of AgNORs in the nuclei of 100 tumor cells (AgNOR counts) was calculated for each case. The association between AgNOR counts and survival was assessed by means of uni- and multivariate survival analyses.

RESULTS

On univariate analysis, AgNOR counts were associated significantly with 5- and 10-year survival rates (95% and 90%, respectively, for thymomas with 5.58 or fewer AgNORs per cell, but only 55% and 44%, respectively, for tumors with more than 5.58 AgNORs per cell; P < 0.0001). Histologic subtypes of the American classification (P = 0.0006) and clinical stage (P < 0.0001) also were correlated with prognosis. The multivariate survival analysis showed that AgNOR counts (P = 0.001), clinical stage (P < 0.001), and age (P = 0.011) were independent prognostic variables. AgNOR counts were associated with histologic subtypes in the American (P = 0.0001) and European (P = 0.005) classifications and with the clinical stage (P < 0.0001). Moreover, thymoma cells and intermingling lymphocytes showed different numbers of AgNORs and patterns of AgNOR distribution.

CONCLUSIONS

Analysis of argyrophilic nucleolar organizer regions provides useful prognostic information for patients with thymomas and offers an exact evaluation of the proliferative activity of the neoplastic cells even for thymomas with prominent lymphocytic infiltration.

Proliferative activity is a significant prognostic factor in male breast carcinoma

The proliferative activity of male breast carcinoma has been investigated using the staining of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody against the proliferating cell nuclear antigen (PC10) and the monoclonal antibody MIB-1 in formalin-fixed, paraffin-embedded specimens from 27 primary male breast carcinomas at diagnosis. A significant correlation was found between survival and AgNOR counts (median of survival 77 months for cases with AgNOR/cell < or = 7.27 but 37 months only for cases with > 7.27 AgNOR/cell; P = 0.001), proliferating cell nuclear antigen scores (median of survival 73 months for cases with proliferating cell nuclear antigen < or = 18.25% versus 41 for cases with proliferating cell nuclear antigen > 18.25%; P = 0.013) and MIB-1 scores (median of survival 73 months for cases with MIB-1 scores < or = 23.5% versus 37 months for cases with MIB-1 scores > 23.5%; P = 0.01). Tumor histological grade was also correlated with prognosis (median of survival 72 months for grade 2 versus 33 months for grade 3 tumors; P = 0.01). Estrogen and progesterone receptors, immunohistochemically detected on paraffin-embedded sections, had no prognostic value. In the multivariate survival analysis, only AgNOR counts (P = 0.007) and tumor size (P = 0.003) had an independent prognostic significance. Our results indicate that methods for assessing the cell proliferation in routinely processed specimens offer significant prognostic information in male breast carcinoma. The finding, together with the lack of prognostic significance for estrogen receptors and progesterone receptors, suggests that male breast carcinoma is biologically different from female breast cancer.

Cell proliferation indices, morphometry and DNA flow cytometry provide objective criteria for distinguishing low and high grade bladder carcinomas

Argyrophilic nucleolar organizer region (Ag-NOR) analysis, proliferating cell nuclear antigen (PC-NA/PC10) and MIB-1 immunohistochemistry, nuclear morphometry and DNA flow cytometry have been performed on formalin-fixed, paraffin-embedded biopsies from 50 patients with transitional cell carcinoma of the urinary bladder. The mean AgNOR count was 6.01 for the 17 grade 1 (G1), 7.59 for the 21 G2 and 13.33 for the 12 G3 carcinomas (p < 0.001). The mean PCNA score was 15.03% for G1, 24.04% for G2 and 40.01% for G3 cases (p < 0.001). The mean MIB-1 score was 11.31% for G1, 17.09% for G2 and 34.47% for G3 carcinomas (p < 0.001). The mean nuclear area was 35.53 microns2 for G1, 38.65 microns2 for G2 and 83.62 microns2 for G3 cases (p < 0.001). Aneuploidy rates were significantly higher (91.7%) in G3 than in G2 (42.9%, p < 0.01) or G1 cases (47.1%, p < 0.05) but not different for G1 versus G2 cases (p = 0.94). While many overlaps of values were seen between G1 and G2 tumours, no overlaps were found between G3 and G1/G2 tumours. Significant differences of values were also found between pTa and invasive tumours (p < 0.0001 for AgNOR count and PCNA score; p < 0.001 for MIB-1 score and mean nuclear area; p < 0.01 for DNA ploidy); however many overlaps were seen. Our findings indicate that the quantitative parameters obtained with different methods are associated with histological grade of bladder urotheliomas and may improve the grading reproducibility. In addition, the absence of overlaps between G3 and G2/G1 carcinomas supports the tendency to classify bladder urotheliomas in only two categories of malignancy.

AgNORs and myeloma prognosis

The argyrophilic nucleolar organizer regions (AgNORs) were analysed in bone marrow biopsies from 80 patients with multiple myeloma (MM) at presentation. The mean AgNOR number per MM cell (AgNOR counts) and their distribution within the nucleus (configuration) were assessed. AgNOR counts were significantly associated with several recognized prognostic factors: Durie and Salmon clinical staging system (p = 0.02), percentage of plasma cells (PCs) in aspirates (p = 0.01) and in bone marrow biopsies (p = 0.0000), pattern of bone marrow involvement (p = 0.0003), calcaemia (p = 0.0005) and creatininaemia (p = 0.0003). AgNOR counts were also associated with the degree of PC differentiation (p = 0.0000). A single central cluster of 2-3 large-sized AgNORs (configuration A) was evident in most G1 MM; one cluster of 4-5 medium-sized dots or two clusters of 2-4 dots (configuration B) were seen in most G2 MM; many small-sized, scattered dots were present in G3 MM (configuration C). AgNOR counts and configuration were related to the prognosis: in the univariate analysis, the 5 year survival rate was 7% for cases with > 4.5 AgNORs/cell and 46% for cases with < or = 4.5 AgNORs/cell (p = 0.01), 53% for configuration A, 12% for configuration B and 0% for configuration C (p = 0.0000). AgNOR counts (p = 0.02) and configuration (p = 0.000) were independent prognostic variables in the multivariate analysis. The AgNOR counts were significantly higher in "fulminant myeloma" than in less aggressive cases (p = 0.002). The plasma cell labelling index (LI%), evaluated in 44 MM patients, showed significant correlation with prognosis: the 5 year survival rate was 51% for LI% < or = 1 and 17% for LI% > 1 (p = 0.02). More than 70% of patients with low LI% had low AgNOR counts and more than 70% of patients with high LI% had high AgNOR counts (p = 0.007). AgNOR counts and configuration reflect the myeloma cell mass, the degree of differentiation and the kinetics of the myeloma cells. They offer an exact evaluation of the tumour characteristics and can be useful additional parameters for MM prognosis.

Comparing flow cytometric analysis and nucleolar organizer region enumeration in archival oral premalignant lesions

Flow cytometric analysis (FCA) and silver colloidal nucleolar organizer region-associated protein staining (AgNOR) have been used individually in assessing the histopathologic nature of various human tumors. However, few researchers have investigated the relationship between the two techniques in a single series. In a retrospective study, we examined 36 premalignant lesions of the oral cavity by FCA and AgNOR on formalin-fixed, paraffin-embedded tissue submitted to the University of Tennessee, Memphis, oral pathology laboratory. Three categories of epithelial dysplasia were represented (9 mild, 9 moderate, 6 severe), as well as four epithelial hyperplasias without dysplasia, three squamous cell carcinomas, and five fibrous nodules as controls. Parameters recorded for each case included age, race, gender, site, light microscopic diagnosis (LMD), DNA index (DI), total proliferative index (TPI), S-phase (S), range of nucleolar organizer regions (RNOR), and mean number of nucleolar organizer regions (MNOR). The average maximum nucleolar organizer region count (AMXNOR) for each LMD category was also calculated. The objective of the study was to determine if FCA or AgNOR aided in the subjective LMD of oral premalignant lesions and if the parameters recorded for the specimens exhibited any positive correlation. The FCA results indicated an abnormal DI in 6 of the 24 dysplastic lesions. A positive partial correlation was seen between DI and MNOR (r = 0.434; P < 0.012) and TPI and S (r = 0.774; P < 0.0001), holding gender and race constant. Additionally, the AMXNOR exhibited a slight tendency to increase for each increasing grade of dysplasia but this could not be confirmed statistically.(ABSTRACT TRUNCATED AT 250 WORDS)

Argyrophilic nucleolar organizer region counts and proliferating cell nuclear antigen scores are two reliable indicators of survival in pharyngeal carcinoma

The proliferative activity of pharyngeal carcinoma has been investigated by means of monoclonal antibody PC10 against proliferating cell nuclear antigen (PCNA/cyclin) and argyrophilic nucleolar organizer region (AgNOR) analysis in formalin-fixed, paraffin-embedded biopsies from 45 primary squamous and undifferentiated carcinomas, prior to therapy. The correlation between AgNOR counts and PCNA(PC10) scores was highly significant (r = 0.73; P < 0.0001) as determined by Pearson's correlation coefficient. Moreover, the univariate Kaplan-Meier survival analysis showed a significant correlation between 3- and 5-year survival rates and the mean AgNOR number per tumour cell (P = 0.0003) or the percentage of PCNA(PC10)-positive cells (P = 0.0001). Our results indicate that both AgNOR counts and PCNA(PC10) scores are reliable markers of the proliferative activity of pharyngeal carcinoma in small, routinely processed biopsies, in which they can allow simultaneous evaluation of the histology and tumour cell kinetics.

Argyrophilic nucleolar organizer region counts and prognosis in multiple myeloma

The prognostic significance of argyrophilic nucleolar organizer regions (AgNORs) has been evaluated in bone marrow trephine biopsies from 64 patients with multiple myeloma (MM) prior to therapy. The univariate Kaplan-Meyer survival analysis showed a significant correlation between survivals and AgNOR counts (median of survival 51.3 months for cases with < or = 4.62 AgNORs per plasma cell (PC) versus 16 months for cases with > 4.62 AgNORs per PC; P = 0.0000) or AgNOR distribution in PC nucleus (AgNOR configuration) (median of survival 71.67 months for cases with tightly grouped AgNORs, 16.26 for partially grouped and 11.74 for dispersed AgNORs; P = 0.001). Significant prognostic correlations were also found for monoclonal immunoglobulin type (P = 0.008), platelet counts (P = 0.0078), serum creatinine level (P = 0.0001), Durie's clinical stage (P = 0.02), percentage of plasma cells in bone marrow biopsies (BMPC%) (P = 0.005), pattern of medullary involvement (P = 0.003) and PC atypia (P = 0.009). Borderline result was detected for the percentage of PCs in aspirates (P = 0.06). No significant correlation was found between prognosis and patients age, sex, haemoglobin level, serum albumin or calcium level, marrow cellularity and excess of haemosiderin. Multivariate survival analysis showed that only two variables were significantly correlated with prognosis: AgNOR counts (P = 0.003) and AgNOR configuration (P < 0.001). In addition, the analysis of variance showed significant association between AgNOR number and platelet counts, haemoglobin level, calcaemia, creatininaemia, clinical stage, percentage of PCs in aspirates, BMPC%, pattern of medullary involvement, PC atypia, marrow cellularity and configuration of AgNORs. Our results indicate that AgNOR counts and configuration have prognostic and diagnostic value and therefore they are useful independent parameters to assess the pretherapeutic aggressiveness of multiple myeloma.

Ag-NOR protein distribution correlates with patient survival in stage I endometrial adenocarcinoma

The relationship between argyrophil nucleolar organizer region (Ag-NOR) protein quantity and prognosis was studied in 33 cases of stage I endometrial adenocarcinoma. Ag-NOR protein quantity was measured by image analysis in silver-stained sections from paraffin-embedded samples of curettings. Patients had a minimum 10-year follow-up. Only 2 out of 25 patients exhibiting a mean Ag-NOR protein area of less than 3 microns2 died of cancer, whereas 5 of the 8 patients with a mean Ag-NOR protein area of more than 3 microns2 died of the disease. The present results demonstrate that the Ag-NOR protein value is closely related to patient survival in stage I endometrial carcinoma and that it is a reliable prognostic indicator in this type of carcinoma.