Nucleolar organiser regions in fibrous proliferations of childhood and infantile fibrosarcoma

Congenital-Infantile Fibrosarcoma: Study of Two Cases and Review of the Literature

Background

Congenital-infantile fibrosarcoma is a rare tumor of the pediatric age. It involves subjects under 5 years of age, and more than 200 cases have been reported in the literature.

Methods

The authors present the clinicopathologic findings of 2 cases and review the literature.

Results

Of our 2 patients, the first was a 2-years and 6-months-old female and the second a newborn male. The female presented a tumor in the retroperitoneum without recurrences or metastasis after 17 months, and the male on left foor with a recurrence after 3 months. Histologically, the tumors were mainly composed of spindle-shaped cells. Immunohistochemically, in both cases, neoplastic cells were positive for vimentin; focal positivity for muscular specific actin was present in the tumor of the female. Ultrastructurally, tumors were composed of mesenchymal cells with fibroblastic and myofibroblastic features. Flow cytometric analysis of the retroperitoneal tumor showed an aneuploid population of neoplastic cells.

Conclusions

Congenital-infantile fibrosarcoma should be considered a borderline tumor; its biologic behavior is better than that of adult fibrosarcoma. Histologic diagnosis is not easy; the microscopic picture may be confused with fibromatosis or with malignant mesenchymal neoplasms. Only a follow-up of many years can confirm the benignancy or malignancy of any individual tumor, even though clinico-pathologic features may be distinctive enough to permit its recognition.

Argyrophilic Nucleolar Organizer Regions in Recurrent Lipomatous Tumors

To analyze the proliferation rate in liposarcomas, we studied two silver staining nucleo lar organizing region (AgNOR) counts in a series of 18 patients with multiple recur rences. In a retrospective analysis of corresponding primary and recurrent tumors, cell nuclear characteristics were assessed by the mean number of AgNORs and the percent age of nuclei with more than five AgNORs per nucleus. The computer-assisted analysis of AgNORs compared with clinicopathologic data showed that two AgNOR counts varied considerably in primary lipomatous tumors and in subsequent recurrences along the course of disease. In most patients, proliferative activity of recurrent tumors varied randomly, without any consistent pattern, except in some liposarcomas that showed transformation to a more aggressive histologic picture. In individual patients, decrease in both AgNOR counts paralleled the prolongation of the recurrence-free interval and vice versa. In this limited series, the AgNOR counts did not prove to be an independent prognostic factor in patients with liposarcoma. Int J Surg Pathol 1 (4) :245-252, 1994

Minichromosome maintenance (MCM) and AgNOR proteins expression in desmoid tumours: a tissue microarray analysis

In the present study, nuclear proliferative proteins: MCM2, MCM5, MCM7, Ki-67 and AgNORs expression was assessed in paraffin sections from sporadic desmoid tumours using a tissue microarray (TMA)-based immuno- and histochemistry, respectively. Nuclear expression of MCM7, where the percentage of positive cells was 0.87% (± 1.64) (range 0-5%), was found in 4/20 (20.0%) cases. In 32/32 (100%) of the examined desmoid cases no expression of nuclear proteins MCM2 and MCM5 was detected. Nuclear expression of Ki-67 was observed in 4/21 (19%) cases. Paraffin sections from 30 cases of desmoid tumours were silver-stained to visualize AgNORs. The following AgNOR parameters were calculated: mean AgNOR number per nucleus (N), mean AgNOR area per nucleus, mean AgNOR dot area per nucleus (A), and mean AgNOR content (C = N/A). In the investigated group the mean values of AgNOR parameters were the following number: 4.34 (± 0.11); area: 0.74 μm2 (± 0.19); dot area: 0.18 m2 (± 0.01), and AgNOR content: 23.73 (± 1.85). The mean AgNOR number per nucleus and mean AgNOR content in desmoid tumours were statistically significantly higher as compared to the controls (tonsil tissue) (p<0.001). This study observed low level of MCM7 and Ki-67 and lack of MCM2, MCM5 proteins expression which may explain commonly known low mitotic activity of desmoid tumour cells. The morphology of dots related to AgNORs (number, area) and their morphometric parameters point to elevated transcriptional activity of desmoid cells.

Studies on argyrophilic nucleolar organizer regions (AgNORs) in a spontaneous mammary gland ductal carcinoma of a captive rhesus monkey

A spontaneous mammary gland ductal carcinoma was diagnosed in a 13-year-old female captive rhesus monkey (Macaca mulatta). The expression of argyrophilic nucleolar organizer regions (AgNORs) was studied to investigate the correlation between the histologic invasiveness and cell proliferation activity assay for predicting the biologic behavior of this tumor type. The results of this study show that the AgNOR size in tumor cells reflect the degree of malignancy when compared with the pattern of peripheral blood lymphocytes of the same individual. This is the first study showing a significant AgNOR feature of a malignant breast tumor in a rhesus monkey and it longs to provide additional diagnostic tool in tumor pathology.

Nucleolar organizer regions (NORs) evaluation of lingual salivary glands of chronic alcoholics

BACKGROUND

Chronic alcoholism has been associated with structural and physiological changes in salivary glands. Studies on a variety of pathologies have suggested that variation in number of nucleolar organizer regions (NORs) reveals conditions of cellular activity. The aim of this work was to examine, through the AgNOR technique, changes in number and size of NORs in lingual salivary glands of chronic alcoholics.

METHODS

Samples of mucous and serous lingual salivary glands were obtained from tongues from autopsies of individuals whose cause of death was hepatic alcoholic cirrhosis. Lingual organs from individuals whose cause of death was accidental were used as controls. Number and size of the AgNORs and nuclear area, in ductal and acinar cells, were evaluated through a digital image analyzer.

RESULTS

Statistical analysis revealed differences (P < or = 0.05) in number of AgNORs in mucous acini and ductal cells. Also, we observed changes in the area of the NORs.

CONCLUSION

These results suggest that in alcoholics the activity of glandular cells, mainly in ductal epithelium, could be affected, modifying synthesis, transport and salivary secretions.

AgNOR are sensitive markers of radiation lesions in squamous epithelia

The possibility of detection of incipient cellular alterations is central to early diagnosis and to clinician's capacity to discriminate between samples that appear similar on routine preparations. We examined the value of silver-stained nucleolar organizer regions (AgNOR) in detecting radio-induced alterations in a model of squamous epithelium biologically similar to oral mucosa. Morphometry of AgNOR has been proven to be of value in the detection of incipient cellular alterations. This method allows for the quantitative evaluation of lesions induced by high doses of radiation long before they become apparent in routine preparations. We herein examine the capacity of AgNOR to reveal the response to low doses of radiation, closer to the therapeutic or accidental dose to which the epithelium of oral mucosa may be exposed.

Nucleolar organizer regions in parosteal and central osteosarcomas

Silver stained nucleolar organizer regions (AgNOR) have revealed differences in the biological behavior of certain entities. This study involves a morphometric analysis of AgNOR in 6 central, classic osteosarcomas and 6 parosteal osteosarcomas. There was a statistically significant difference in the number of AgNOR per nucleus between central and parosteal osteosarcomas. Single AgNOR volume was smaller in central osteosarcomas as compared to parosteal osteosarcomas. However, this difference did not reach statistical significance. The parameter AgNOR number per nucleus revealed a cut off value such that 100% of central osteosarcoma cases lay above this value and 100% of parosteal osteosarcoma cases lay below this value. AgNOR demonstration involves a simple technique which can be performed on formalin fixed, paraffin embedded file material. Thus, it may be prudent to routinely assess AgNOR as a contributor to the determination of the pathophysiology of osteosarcomas.

AgNOR mark epithelial foci in malignant transformation in hamster cheek pouch carcinogenesis

Hamster cheek pouch mucosa is an accepted model of oral carcinogenesis. We herein examined the value of morphometric evaluation of silver-stained nucleolar organizer regions (AgNOR) in the detection of epithelial foci in malignant transformation following dimethyl-1,2-benzanthracene-induced carcinogenesis of hamster cheek pouch. AgNOR-related parameters were analyzed at different stages of the process of carcinogenesis (control epithelium, epithelium with no unusual microscopic features, "dysplastic" epithelium, exophytic and endophytic carcinomas). Morphometric evaluation of AgNOR revealed incipient cellular alterations which were not evident in routine preparations and contributed to the characterization of different stages of carcinogenesis in this model.

Nucleolar organizer region (NORs) in pseudocarcinomatous hyperplasia and squamous cell carcinoma of the oral mucosa

Counts of nucleolar regions (NORs) demonstrated by a silver staining technique in paraffin sections, have been used to distinguish benign from malignant lesions. AgNORs were studied in 24 biopsies from oral cavity (5 cases of normal oral mucosa, 5 of pseudocarcinomatous hyperplasia and 14 of squamous cell carcinoma, subdivided according to degree of differentiation: 5 grade 1, 5 grade 2 and 4 grade 3) to find whether they were helpful in distinguishing pseudocarcinomatous hyperplasia due to chronic parasitic infections from squamous cell carcinoma. Two methods of counting AgNORs were used: (A) a simpler one which counts nucleolar clusters (AgNU) and satellite AgNORs and the other (B) counting all individual AgNORs, including those within AgNUs. In both methods the lowest mean values were observed for grade 3 carcinoma, while the highest belonged to grade 2 carcinoma. The simpler method (A) was the most useful because AgNU counts showed significant difference when pseudocarcinomatous hyperplasia was compared with grade 1 and 2 carcinomas, which are the most difficult to discriminate from it. However the overlapping of values render the technique of limited use in individual cases.

Nucleolar organizer regions (NORs)

Counts of nucleolar regions (NORs) demonstrated by a silver staining technique in paraffin sections, have been used to distinguish between benign and malignant lesions. AgNORs were studied in 24 biopsies from oral cavity (5 cases of normal oral mucosa, 5 of pseudocarcinomatous hyperplasia and 14 of squamous cell carcinoma, subdivided according to degree of differentiation: 5 grade 1, 5 grade 2 and 4 grade 3) to find whether they were helpful in distinguishing pseudocarcinomatous hyperplasia due to chronic parasitic infections from squamous cell carcinoma. Two methods of counting AgNORs were used: (A) a simpler one which counts nucleolar clusters (AgNU) and satellite AgNORs and the other (B) counting all individual AgNORs, including those within AgNUs. In both methods the lowest mean values were observed for grade 3 carcinoma, while the highest belonged to grade 2 carcinoma. The simpler method (A) was the most useful because AgNU counts showed significant difference when pseudocarcinomatous hyperplasia was compared with grade 1 and 2 carcinomas, which are the most difficult to discriminate from it. However the overlapping of values render the technique of limited use in individual cases.

Nucleolar organizer regions in follicular tumors of the thyroid

BACKGROUND

Nucleolar organizer regions (NORs) are loops of ribosomal DNA that occur in nucleoli and that transcribe to ribosomal RNA. NORs have been identified by means of the Ag-NOR technique in routinely processed tissues, and were found to be of discriminative value between some types of benign and malignant lesions.

METHODS

Follicular lesions of the thyroid (17 adenomas and 25 carcinomas) were examined. Ten normal thyroids served as the control group. All slides were stained by the Ag-NOR technique and the number of Ag-NOR dots were counted in 50 randomly selected cells. The mean number of Ag-NORs was calculated for each case. Data were statistically analyzed by the Student's unpaired t test.

RESULTS

The mean Ag-NOR counts were statistically higher in follicular carcinomas as compared to either follicular adenomas or the normal thyroid. Higher Ag-NOR counts were found in the more aggressively behaving tumors.

CONCLUSIONS

It is suggested that the Ag-NOR technique could be of use as an adjunct to diagnostic histopathology and as an indicator of biologic behavior in follicular tumors of the thyroid.

Nucleolar organizer regions in lining epithelium adjacent to squamous cell carcinoma of human oral mucosa

BACKGROUND

The value of silver staining of nucleolar organizer regions (AgNOR) counts as a diagnostic aid has been reported for several neoplastic entities. Previous studies have proved the value of the morphometric evaluation of AgNOR in the detection of incipient cellular alterations.

METHODS

A morphometric analysis of AgNORs was performed in oral mucosa epithelium adjacent to squamous cell carcinoma compared with normal mucosa epithelium and the carcinomatous parenchyma.

RESULTS

Highly statistically significant differences in all 5 AgNOR-related parameters assessed were found between normal mucosa and mucosa adjacent to cancer. Conversely, the corresponding nuclear parameters failed to exhibit significant differences. The parameter AgNOR contour index plotted for individual cases affords a cutoff value that could prove useful in identifying epithelia at early stages of transformation.

CONCLUSIONS

AgNOR evidenced significant variations in epithelium adjacent to oral squamous cell carcinoma, which did not exhibit morphologic signs of atypia. Based on this study, AgNOR would be a quantitative, discriminative aid, easy to monitor in a pathology laboratory, in detecting incipient cellular alterations. These findings contribute to the issue of early diagnosis and to the knowledge of tumoral growth.

The value of the AgNOR staining method in identifying carcinoma in situ testis

An early and reliable diagnosis is necessary in order to have the chance of a curative therapy of Carcinoma in situ testis (Cis). Forty-six testicular biopsies were investigated to assess the value of the AgNOR staining method in comparison to placental alkaline phosphatase (PLAP) immunostaining. Both methods provided corresponding results and identical tumor cells were recognized in serial sections. The mean AgNOR counts per nucleus were 26.86 (19-52, SD: 2.68) for CIS cells, 8.18 (5-14, SD: 2.20) for spermatogonia and 12.96 (9-18, SD: 2.44) for Sertoli cells, without the counts overlapping within these three groups. Even single CIS cells are easily and reliably recognizable by their typical AgNOR pattern and their high AgNOR count per nucleus. The independent estimation of 9 testicular biopsies with the AgNOR staining method and the PLAP immunostaining correspondingly revealed 7 biopsies with CIS. Two biopsies lacked tumor cells. The AgNOR staining method can be recommended as an additional diagnostic tool in identifying CIS, because of the short and convenient staining procedure, low costs and the applicability on formalin-fixed and paraffin-embedded material.

So-called congenital-infantile fibrosarcoma: does it exist and what is it?

Congenital-infantile fibrosarcoma (CIFS) is a cellular, mitotically active neoplasm with a paradoxically limited biologic potential in most cases. Its phenotype and proliferative features have been incompletely explored with inconclusive results. We studied the clinical, pathologic, immunohistochemical, and flow cytometric features of 26 cases (16 males, 10 females; 92% of cases detected within the first year life; 11 on extremities, 10 on the trunk, 5 in the head and neck). All displayed interlacing fascicles of spindle cells with focal necrosis, mitoses, and a focal hemangiopericytomatous vascular pattern. Immunohistochemically, 22 of 22 cases were reactive for vimentin. Other markers were present in a minority of cases. Flow cytometry of formalin-fixed, paraffin-embedded tissue in 10 cases demonstrated moderate to high proliferation activity and diploid DNA content in nine cases. Follow-up of all 26 patients revealed 20 patients alive and well, 15 without evidence of recurrence, and 5 with a small residual mass. Six patients had died of tumor, none had distant metastases. Patients with tumors in the head and neck or deep truncal soft tissues, including mesentery, had a poor prognosis because of local extension. CIFS is a clinically and morphologically homogeneous condition with considerable immunophenotypic diversity. Diploid DNA content in the majority of cases suggests that it may not be a fully expressed sarcoma. The clinicopathologic features are sufficiently distinctive to permit recognition and warrant conservative initial treatment in most cases. "Fibrosarcoma" is a term of convenience rather than of nosologic certainty.

Nucleolar organizer regions as markers of incipient cellular alterations in squamous epithelium

Transcriptionally active nucleolar organizer regions identified by silver staining (AgNOR) vary in number with cellular activity and/or malignant transformation and have been used as a diagnostic tool. A morphometric study of AgNORs was performed in an experimental model of irradiated squamous epithelium (Wistar rat sole skin) 4, 8, and 14 hours and 1, 2, 5, and 7 days post-irradiation with 50 Gy of x-rays. A statistically significant and progressive rise in AgNOR average volume of up to 238% and reduction in AgNOR number/nucleus of up to 40% were detected as a function of post-irradiation time. A statistically significant 46% increase in AgNOR volume was detected as early as 8 h post-irradiation, when no histological changes were observable in routine preparations. These results suggest that AgNORs may be useful as a quantitative marker of incipient changes in cellular activity and caution against the indiscriminate use of AgNORs in the follow-up of lesions which may have been exposed to radiotherapy. Furthermore, this study suggests the possibility of using AgNORs as a sensitive biological dosimeter in cases of uncontrolled exposure to radiation.

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)

Argyrophilia in nucleolar organizer regions (AgNOR) in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of the salivary glands

Nine cases of adenoid cystic carcinomas (ACC) and three cases of polymorphous low-grade adenocarcinomas (PLGA) of the salivary glands from the Surgical Oral Pathology Service of the University of São Paulo School of Dentistry were examined by means of the silver-staining nucleolar organizer regions (AgNOR) technique. Quantitative and dimensional analyses of NORs were carried out. Our findings suggest that solid and cribriform patterns of ACC have a higher cellular activity than that presented by tubular ACC and PLGA.

Nucleolar organizer regions in human maxillary sinus squamous cell carcinoma

A silver colloid technique for nucleolar organizer regions (AgNOR) was applied to paraffin sections of maxillary sinus squamous cell carcinomas (MSSCC) of 25 patients. The patients were divided into two groups, one with MSSCC recurring in the primary lesion after treatment with radiotherapy, chemotherapy and/or surgery and one without recurrence. Notable differences between the numbers of NOR in neoplastic epithelia and the normal mucosa were observed (P = 0.0001), but there were no differences between the numbers of NOR in the recurrent and non-recurrent carcinomas. This investigation found no prognostic importance in the number of AgNOR in MSSCC.

Importance of interphase nucleolar organizer regions in tumor pathology

The importance of the distribution of silver-stained nucleolar organizer regions (Ag-NORs) in interphase nuclei for diagnostic and prognostic purposes in tumor pathology has been reviewed. The available data demonstrated that interphase Ag-NOR evaluation may be of help in distinguishing malignant from hyperplastic or normal cells. On the other hand, there is increasing evidence that a relationship exists between the quantity of interphase Ag-NORs and the prognosis of malignant tumors: the greater the number of interphase Ag-NORs, the worse is the prognosis. This can be explained by the observation that the interphase Ag-NOR quantity is strictly related to the cell proliferation rate. The procedures used for the measurement of the interphase Ag-NOR quantity are also critically discussed.

Nucleolar organizer regions in congenital mesoblastic nephroma

A review of 78 renal tumors in patients under 6 months of age revealed 35 congenital mesoblastic nephromas (CMNs). Based on cellular criteria, 14 were classified as classical, 4 as partly cellular, and 17 as cellular CMN. The mean ages were 24, 11, and 70 days, respectively. There were 13 intrarenal tumors (stage I) but 9 classical, 3 partly cellular, and 5 cellular CMNs extended to the perirenal fat (stage II) and 5 cellular tumors ruptured (stage III). In order to assess cellular proliferative activity, silver staining of nucleolar organizer region (Ag-NOR) proteins was performed on 19 CMNs. The number of Ag-NOR dots per cell was significantly lower in classical and partly cellular CMN than in cellular CMN, whatever the stage (P < .01). Within the cellular CMNs, the mean number of Ag-NOR dots was statistically higher in the single case that recurred with fatal outcome (P < .02). Counting of Ag-NOR dots appears to be a reproducible method for evaluating the biologic potential of CMNs. The number of Ag-NOR dots, DNA content measurements, the histological subclassification, and the presence or absence of tumor at the surgical margins may be useful features in selecting those patients who will benefit from further treatment after nephrectomy.

Nucleolar organizer regions in uterine sarcomas

Nucleolar organizer regions demonstrable by silver staining technique (AgNORs) are loops of nucleolar DNA transcribing to ribosomal RNA. This report quantifies AgNORs in normal endometrium and myometrium, and in leiomyomas and homologous sarcomas of the uterus. The mean AgNOR number in leiomyosarcomas was significantly higher than that in normal myometrium and that in leiomyomas, whereas no significant difference was observed between normal myometrium and leiomyomas. The mean AgNOR count in low-grade endometrial stromal sarcomas was significantly higher than that in normal endometrial stroma, and significantly lower than that in the high-grade variant of the same tumour. The epithelial component of malignant mixed müllerian tumours exhibited a significantly higher mean AgNOR number than normal endometrial epithelium, and the stromal component of these tumours showed a significantly higher mean AgNOR count than normal endometrial stroma and normal myometrium, respectively. The AgNOR count was significantly correlated with the mitotic rate in leiomyosarcomas, in high-grade endometrial stromal sarcomas, and in the epithelial and mesenchymal portions of mixed müllerian tumours, whereas no statistically significant correlation was observed in low-grade endometrial stromal sarcomas. Increased AgNOR counts have been reported for some kinds of malignant tumours in various organs, compared with normal tissues and benign tumours. This study demonstrates a similar increase when homologous uterine sarcomas are compared with histogenetically related normal and neoplastic tissues. AgNOR counting might be a useful adjunct in the classification and grading of uterine tumours.

Morphometric study of nucleolar organizer regions in human oral normal mucosa, papilloma and squamous cell carcinoma

A morphometric study of nucleolar organizer regions (NOR) was performed to analyze their distribution, volume, number and shape in the different strata of human normal oral mucosa epithelium and papilloma and in squamous cell carcinoma employing microphotographs of silver-stained paraffin sections. The different NOR-related parameters evidenced significant differences between normal mucosa, papilloma and squamous cell carcinoma. The functional polarity of normal mucosa epithelium and of papilloma is also evidenced in terms of NOR-related parameters. The discriminative value of certain NOR parameters was demonstrated.

Argyrophylic nucleolar organiser regions (AgNOR's) as a prognostic indicator in breast carcinoma

Silver staining nucleolar organiser regions (AgNOR's) were determined in archival histological specimens of breast carcinoma. Representative samples from forty-eight female patients were counted manually for AgNOR's--median 3.85 (range 1.1-10.2 AgNOR's per cell). Taking the median value of 3.85 as a cutoff, the patients were divided into two groups: A = Those with AgNOR counts > 3.85; B = Patients with AgNOR counts < or = 3.85. The 5 year survival was 21% in group A and 85% in group B (p < 0.001). There was no significant correlation between AgNOR's and tumour size, lymph node status, tumour grade, menopausal status and oestrogen receptors. We conclude that nucleolar organiser regions may be useful as a prognostic indicator in breast carcinoma especially in patients in whom other prognostic information is unavailable.

Glial fibrillary acidic protein (GFAP) expression and nucleolar organizer regions (NORs) in human gliomas

The frequency of nucleolar organizer regions (NORs) in each glioma tissue and the relation between the expression of glial fibrillary acidic protein (GFAP) and the frequency of NORs was investigated. The number of Ag-NORs per cell for glioblastoma multiforme was significantly higher than that for anaplastic astrocytoma (P less than 0.05) and that for astrocytoma (P less than 0.01). The number of Ag-NORs per cell for GFAP-positive cells was significantly lower than that for GFAP-negative cells in each histopathological grade (P less than 0.01). Moreover, the linear relationship was demonstrated between the Ag-NORs numbers of GFAP-negative cells and bromodeoxyuridine (BUdR) labeling indices. From these results, it is concluded that many GFAP-positive glioma cells may have low growth potential in glioma tissue and GFAP-negative cells may have a close relation to cell proliferation. The combination of immunohistochemical and silver colloid staining is a useful method for investigating the biological characteristics of brain tumors.

Nucleolar organizer regions in aggressive and nonaggressive basal cell carcinoma of the skin

Nucleolar organizer regions (NOR) were investigated on routine paraffin-embedded histologic sections of 11 aggressive basal cell carcinomas that recurred and/or metastasized (BCC2) and 11 nonaggressive basal cell carcinomas (BCC1). The absolute number of NOR per nucleus was higher in BCC2 than in BCC1, and their distribution pattern was also different. In fact, the means of argyrophilic staining of NOR (AgNOR) counts in the two groups of tumors by two observers were 6.56 with a SD of 1.98 for the nonaggressive and 9.48 with a SD of 2.12 for the aggressive basal cell carcinomas. A statistical analysis of these data using the Student's t test confirmed these observations (t = 64.49). Problems in the evaluation of NOR and possible comparison with other experiences are also discussed. The authors conclude that a quantitative assay of AgNOR and perhaps their distribution pattern may provide information useful to recognize BCC2 and hence may be of help in their prognostic prediction.

Argyrophilic nucleolar organizer regions in benign hyperplastic and cancerous human prostates

Argyrophilic nucleolar organizer regions (AgNORs) were examined histologically in cells of benign hyperplastic and cancerous human prostates. Individual dots of AgNORs inside nucleus that were stained as separate granules or as parts of clusters were counted as one, and the average number of dots per cell was obtained by counting 100 nuclei. The number in epithelial cells was similar to that in stromal cells of hyperplastic prostates. In cancerous prostates, the number was larger than in hyperplastic prostates and increased along with upgrading. The number in incidental cancers was smaller than in clinical cancers as compared with cells of the same Gleason pattern. Number correlated with T factor, but not with N and M factors. Response to treatment and cause-specific survival in stage D2 patients receiving endocrine therapy did not correlate with number, although a relationship between Gleason pattern and survival was shown in these patients. It was concluded that AgNORs might not be an indicator to predict prognosis after endocrine therapy, since a number of AgNORs did not influence response to the therapy.

Silver-stained nucleolar organizer proteins in chondrosarcoma

Silver-stained nucleolar proteins (AgNORs) were counted in primary chondrosarcomas of three histologic grades and in metastatic chondrosarcomatous lesions in the lung. The AgNOR numbers of neoplastic cells in primary tumors increased stepwise from grade 1 (4.42 +/- 1.11) through grade 2 (4.94 +/- 1.31) to grade 3 (6.97 +/- 1.10). There was a significant difference in AgNOR numbers between grade 3 and both grades 1 and 2 (p less than 0.001). Furthermore, the mean number of AgNORs in metastatic lesions (9.75 +/- 0.83) was significantly higher than that in primary sites (p less than 0.001). The number of AgNORs therefore reflects the grade of the chondrosarcoma. The results in the present study indicate that silver colloid staining is a useful technique for determining the histologic grade and evaluating the proliferative activity of chondrosarcomas.

Nucleolar organizer regions in the normal, hyperplastic and carcinomatous epithelium of endometrium

A silver colloid technique to identify nucleolar organizer region associated protein (AGNORs) has been applied to paraffin sections in a total of 43 endometrial hyperplasias (24 adenomatous and 19 adenocystic) 26 endometrial carcinomas and 22 normal endometria (11 of proliferative and 11 of secretory phase). A morphometric analysis of highly magnified photographic images of AGNORs in light microscopic preparations was performed. Malignant tumor cells showed significantly higher AGNOR numbers, maximum diameter and mean area compared with normal and hyperplastic endometrium, with the exception of adenocystic hyperplasia whose Dmax and mean area were significantly larger. Regarding the distribution pattern of AGNOR dots in the cases studied, it was found that normal and hyperplastic endometrium had a mainly clustered distribution while endometrial adenocarcinomas revealed a scattered one. The significant differences observed in the number of AGNORs, their size and mean area between benign and malignant endometrial epithelia suggest that the AGNOR staining technique is of diagnostic importance in distinguishing between these two groups.

Silver-stained nucleolar organizer regions in the normal, hyperplastic and neoplastic endometrium

The numbers of silver-stained nucleolar proteins (AgNORs) were counted in hyperplastic and neoplastic lesions of the endometrium and compared with those of normal proliferative and secretory phase endometrium. In glandular cells in the normal menstrual cycle, the mean number of AgNORs in proliferative phase endometrium (3.8) was significantly higher than that in secretory phase endometrium (2.7, P less than 0.05). The mean number of AgNORs in well-differentiated endometrioid type adenocarcinoma (5.5) was significantly higher than that in both complex hyperplasia without cytological atypia (3.6, P less than 0.01), and simple hyperplasia (3.3, P less than 0.01). Mean AgNOR counts in complex hyperplasia with cytological atypia were greater than those in both complex hyperplasia without cytological atypia (P less than 0.05) and simple hyperplasia (P less than 0.05). Thus, complex hyperplasia with cytological atypia appears to be a direct precursor of well-differentiated endometrioid type adenocarcinoma. These findings suggest that the mean numbers of AgNORs are increased in neoplastic changes in the endometrium, and the one-step colloid method for AgNORs may therefore be a simple and useful technique to examine proliferative activity in neoplastic and pre-neoplastic endometrial cells.

Rapid detection of proliferating potential in human brain tumors by nucleolar organizer region staining on squash preparations

Rapid detection of the proliferating potential of 37 human brain tumors was attempted using squash preparations stained by a silver colloid technique for argyrophilic protein associated with nucleolar organizer regions (AgNORs). Less than 1 h was required for staining. The mean number of AgNORs in cell nuclei of malignant or recurrent brain tumors (16 cases) including meningeal sarcoma, recurrent meningioma, recurrent craniopharyngioma, anaplastic astrocytoma, glioblastoma multiforme and metastatic brain tumor was 3.18, and the number for benign brain tumors (21 cases) including meningioma, neurinoma, pituitary adenoma, benign astrocytoma, ependymoma, and adenoma of lachrymal gland was 1.85. The former value was significantly greater than the latter value (P less than 0.001). These results indicate that quantitative analysis of AgNORs in brain neoplastic cells, using squash preparations, is useful to differentiate malignant from benign tumors within 1 h. Thus, this method provides rapid and useful information about the proliferative potential of human brain tumors even during operation.

Infantile desmoid-type fibromatosis. Morphological features correlate with biological behaviour

It is generally agreed that the biological behaviour of infantile desmoid-type fibromatosis is unpredictable in terms of the likelihood of local recurrence. We evaluated the prognostic importance of the number of slit-like blood vessels with a mean diameter of less than 20 microns and of the quantity of undifferentiated mesenchymal cells. In addition, we studied the immunophenotypic characteristics of the proliferating cells and their nucleolar organizer region (AgNOR) numbers and distribution. Statistical analysis showed that the tendency to recur locally was correlated with larger numbers of slit-like blood vessels and undifferentiated mesenchymal cells. The proliferating cells were identified by immunohistochemistry as myofibroblasts. No correlation was found between AgNOR numbers and clinical course of the disease. We conclude that histological features easily evaluated by conventional light microscopy provide useful information on the possible course of infantile desmoid-type fibromatosis.

Blood transfusion and laryngeal cancer

Evidence exists to suggest a detrimental effect of blood transfusion on survival after resection for malignant disease. Immune suppression due to transfusion has been implicated, though this remains unproven. We have conducted a retrospective study of 69 patients (38 transfused, 31 not transfused) with squamous carcinoma of the larynx to assess the effect of blood transfusion on survival after laryngectomy. Patients were compared for age, sex, smoking habit, tumour site and stage, grade of operating surgeon, preoperative haemoglobin, tumour nucleolar organizer region status, and operation time. The minimum follow-up was 5 years. In the transfused group 21/38 died as a result of their malignant disease and only 4/31 in the untransfused group. This difference was highly significant (P less than 0.001, chi-squared test) and using a multivariate analysis the only variable associated with a decreased survival time was whether a blood transfusion had been received. We conclude that peri-operative blood transfusion is associated with decreased survival after laryngectomy. However, whether this association is causal remains unproven.

Prognostic relevance of silver-stained nucleolar proteins in sarcomatoid carcinomas of the breast

Fourteen cases of sarcomatoid carcinomas of breast were evaluated by means of a silver technique that selectively stains proteins located in the nucleolar organizer regions (Ag-NORs). The mean area of Ag-NORs (MNORA) was in each case quantitatively analyzed by means of an automated image analyzer. Patients who died early of the disease had a higher MNORA than patients who survived longer than 3 years. The difference was statistically significant. Ag-NORs might be a novel parameter of prognostic relevance in specific cases.

Assessment of proliferative potential in gliomatosis cerebri

The proliferative potential of neoplastic cells in two cases of gliomatosis cerebri was investigated by a combined staining technique, a one-step silver colloid method for nucleolar organizer region-associated protein (AgNOR) and immunohistochemistry for fibrillary acidic protein (GFAP). The neoplastic cells in the two cases had an abnormal shape and showed positive GFAP immunostaining in their cytoplasm. The numbers of AgNORs were counted in central and peripheral lesions of the neoplastic field in each case. The mean AgNOR scores in neoplastic cells were almost the same as those of nonneoplastic astrocytes in both the central and the peripheral lesions. These values were almost equal to the AgNOR score of low-grade gliomas. These findings indicate that gliomatosis cerebri has an invasive character in the central nervous system and often shows a malignant tendency, but its proliferative potential is significantly lower than that of high-grade gliomas.

Distribution and estimation of nucleolar organizer regions in various human lung tumours

A quantitative study of nucleolar organizer regions in human lung carcinomas was carried out on routinely processed paraffin embedded tissue sections. We examined 104 lung carcinomas including 38 squamous cell carcinomas, 36 adenocarcinomas, 18 large cell anaplastic carcinomas, 6 small cell carcinomas and 6 carcinoids. No significant differences were found in mean number of NORs between squamous, adenocarcinoma and undifferentiated carcinomas including large cell and small cell carcinomas. Carcinoids had comparatively lower means except for one typical carcinoid. Considering the high incidence of overlap between ranges of NOR counts in these groups of tumours and in agreement with the only other study of lung tumours (which comprised only carcinoids and small cell carcinomas), we conclude that this technique cannot be reliably used to discriminate between various histologic types of lung cancers. However, long term follow up of these patients is needed to establish the value of the AgNOR technique for prognostic guidance.

Acrocentric interconnections and NOR variants in human lymphocytes

Acrocentric interconnections and NOR (nucleolus organizer region) variants are frequently observed in silver-stained metaphase preparations from lymphocytes of phenotypically normal individuals. The types of interconnections and of NOR variants are outlined. It is speculated that the satellite acrocentrics (both normal and variant) are the consequence of breakage and recoiling of these interconnections. Awareness of these two features of the human genome may facilitate understanding of the NOR/nucleolus interaction(s) in such important processes as nucleolus formation and in development and/or diagnosis of disease states (i.e., malignancy).

Argyrophilic nucleolar organiser region (AgNOR) staining in normal bone marrow cells

Fifteen normal bone marrow aspirates were stained with the agyrophilic nucleolar organiser region (AgNOR) method. The results of the specific staining AgNORs as well as nuclear and cytoplasmic staining were analysed. A system was devised to characterise precisely the AgNORs present in the nuclei of bone marrow cells. Particular types of bone marrow cells had a characteristic AgNOR and non-AgNOR staining pattern. The bone marrow cells were identified easily and reliably with AgNOR staining and the method was especially useful for lymphocytes, plasma cells, erythroid cells, basophils/mast cells, monocytes and cells containing haemosiderin. The immature haemopoietic cells exhibited more and larger AgNORs than the more mature cells. It is concluded that AgNOR staining can be used to study bone marrow cells by providing additional information when used in conjunction with conventional stains.

Intratubular germ cell neoplasia of the testis: identification by placental alkaline phosphatase immunostaining and argyrophilic nucleolar organizer region quantification

We assessed the value of placental alkaline phosphatase (PLAP) immunostaining and argyrophilic nucleolar organizer region (AgNOR) quantification as techniques for the identification of intratubular germ cell neoplasia (ITGCN), and compared them with hematoxylin-eosin and periodic acid-Schiff staining. We examined 46 malignant testicular germ cell tumors for the presence of ITGCN; 43 had sufficient tubules available for assessment. We also examined 16 cryptorchid testes, 16 testicular biopsies from 10 subfertile men, and 12 normal adult intrascrotal testes. In tubules adjacent to invasive tumors, hematoxylin-eosin staining identified 30 cases (70%) of ITGCN, while PLAP and AgNOR staining identified 36 cases (84%). All the seminomas (18) and 22 of 28 nonseminomatous germ cell tumors were PLAP-positive and had high AgNOR counts. Intratubular germ cell neoplasia was not identified in the other groups examined; germ cells in these groups were PLAP-negative and had low AgNOR counts. Cells of ITGCN showed cytoplasmic block positivity with periodic acid-Schiff staining but this was not a consistent finding. We conclude that ITGCN is present adjacent to most invasive germ cell tumors, and is reliably identified by hematoxylin-eosin staining when fully developed. Periodic acid-Schiff staining was not helpful as normal spermatogonia were also positive. Staining with PLAP and AgNOR were useful diagnostic adjuncts, but results with PLAP were easier to interpret.

Identification of nucleolar organizer regions in non-neoplastic and neoplastic hepatocytes by the silver-staining technique

The silver staining technique to demonstrate nucleolar organizer region (NOR)-associated proteins (AgNORs) was applied to a variety of liver tissues, including chronic persistent hepatitis (CPH), chronic active hepatitis (CAH), liver cirrhosis (LC), liver cell dysplasia (LCD), focal nodular hyperplasia (FNH), adenomatous hyperplasia (AH) and hepatocellular carcinoma (HCC). In the present study, only discrete, easily counted black dots within nuclei and silver-stained nucleolus were counted under a magnification of x400 without oil-immersion objectives. The mean AgNOR counts of HCC and LCD were significantly higher than that of normal hepatocytes, and 77% of cases of LCD and 56% of HCC had mean AgNOR counts more than 2, whereas those in CPH, CAH, LC, FNH and AH were always less than 2 and were not different from that of normal hepatocytes. Among HCC, the mean number of AgNORs increased with the grade of the tumor. However, the AgNOR counts of grade I HCC were always less than 2 and overlapped with those of normal hepatocytes and other benign categories. All cases with mean AgNOR counts of more than 2 turned out to be HCC, except LCD which exhibited characteristic histologic appearances easily distinguished from HCC. These findings suggest that AgNORs could be quantitatively useful in evaluating the grade of HCC, even under routine microscopic examination without oil-immersion objectives, and mean AgNOR counts of more than 2 per nucleus are hallmarks of HCC.

Silver colloid staining technique for analysis of glioma malignancy

A silver colloid staining technique for identifying nucleolar organizer region-associated proteins (Ag-NOR's) was applied to 51 human gliomas. These comprised 20 glioblastomas multiforme, 15 anaplastic astrocytomas, and 16 astrocytomas, in which the mean numbers of Ag-NOR's per cell (+/- standard error of the mean) were 2.51 +/- 0.12, 2.01 +/- 0.10, and 1.76 +/- 0.06, respectively. Significant differences among these were recognized, and the mean number of Ag-NOR's paralleled the degree of histopathological malignancy. In 16 cases, studies were performed of the number of Ag-NOR's and the S-phase fraction by in vitro labeling using antibromodeoxyuridine monoclonal antibody. A linear relationship was demonstrated between these two factors (r = 0.857, p less than 0.001), although some scatter was seen. In 32 adult patients, the correlation between the number of Ag-NOR's and the prognosis was estimated. The results demonstrated that the group containing patients with less than 1.80 Ag-NOR's per cell had a better prognosis than the group with 1.80 Ag-NOR's or more. Thus, the number of Ag-NOR's reflected the degree of histopathological malignancy, S-phase fraction, and prognosis. Silver colloid staining for Ag-NOR's is a simple, rapid, and reproducible method for estimating the proliferative potential of human gliomas without requiring a complicated technique.

Correlation between nucleolar organizer region staining and Ki-67 immunostaining in human gliomas

Fourteen cases of various grades of gliomas were investigated by an immunohistochemical method using a monoclonal antibody, Ki-67, which reacted with a nuclear antigen in proliferating cells, and the correlation between Ki-67 labeling index and the number of nucleolar organizer regions stained by an argyrophilic method. Four normal brain tissue samples without neoplastic cells, which were obtained at surgery, were also examined for nucleolar organizer region staining. Both the mean number of nucleolar organizer regions and the percentage of Ki-67 positive cells well reflected the histological grade of gliomas (astrocytoma grade 2: Ki-67, 0.5% and nucleolar organizer regions, 1.6; astrocytoma grade 3: Ki-67, 3% and nucleolar organizer regions, 2.5; astrocytoma grade 4: Ki-67, 5.2% and nucleolar organizer regions, 2.8). Also, the percentage of Ki-67 positive cells and the mean number of nucleolar organizer regions were found to be linearly related (r = 0.91). Both values of high-grade astrocytomas were significantly greater than those of low-grade astrocytomas (p less than 0.01 and p less than 0.001). Thus, the mean number of nucleolar organizer regions as well as Ki-67 labeling index reflect the proliferating potential of gliomas.

Diagnostic value of silver-stained interphasic nucleolar organizer regions in breast tumors

Seventy-six specimens of normal breast tissue and benign and malignant breast lesions were studied to assess the mean area occupied by silver-stained proteins of the nucleolar organizer regions (MNORA) of the nucleolus. The assessment was performed with a computer-assisted image analyzer. The results indicate that only 30% of malignant lesions have a MNORA value greater than that of normal breast tissue or benign lesions. On the other hand, MNORA values of ductal carcinoma in situ were significantly greater than those of epitheliosis (papillomatosis). MNORA values were also significantly different in grade I and grade III invasive ductal carcinomas, the latter exhibiting the highest MNORA values of all the cases observed. Evaluation of MNORA values may therefore help in differentiating benign epithelial proliferations from ductal carcinomas in situ. Furthermore, because there is evidence that MNORA values are indicative of the cell duplication rate, MNORA values may ultimately be considered an objective prognostic parameter in addition to grading for invasive ductal carcinomas.