Nucleolar organizer regions and PCNA expression in prostatic cancers

Assessment of the potential of pathological stains in human prostate cancer

BACKGROUND

Incidence of prostate cancer in India is relatively low compared to the western countries. Nevertheless, an increase by 1% yearly has been recorded in the last three years, thereby making early diagnosis of prostate cancer crucial for controlling its incidence. Differentiating between benign and malignant lesions has been a diagnostic dilemma, especially in prostate pathology. This is compounded by unavailability of modern tests in certain regions of developing nations.

METHODS

A cohort of one hundred seventy six prostatomegaly patients used in the current study was obtained both retrospectively and prospectively at the Jawaharlal Nehru Medical College, Sawangi, Wardha, Maharashtra, India. Details of the patients were recorded which included their age. The samples were then cut into 5 sections, each of 5micron thickness. One section was preserved and the other 4 sections were subjected to Hematoxylin and Eosin (H and E), Periodic Acid-Schiff (PAS), Alcian Blue and AgNOR stains. Degree of differentiation was estimated and correlated with the Gleason score and the outcome of the stainings.

RESULTS

Majority of benign prostatic hyperplasia and all primary carcinoma patients were in their sixth to eighth decade of life. While all the benign lesions were negative, 6 out of 9 primary prostate carcinomas were positive for Alcian Blue stain. Majority of both benign and malignant lesions were positive for Periodic Acid Schiff (PAS) stain. In terms of Argyrophilic Nucleolar Organiser Region (AgNOR) count per nucleus, the value in benign lesions was observed to be half the count observed in malignant lesions per nucleus.

CONCLUSION

Although the potential use of the orthodox stains individually may not serve the purpose to differentiate between benign and malignant lesions, together they may have the potential to identify relatively more malignant cases. This may be helpful especially in low socio-economic countries and rural areas where molecular based tests may not yet be available.

Study of immunohistochemistry in prostatic lesions with special reference to proliferation and invasiveness

Prostatic lesions on routine staining sometimes cause diagnostic dilemma especially in premalignant lesions like atypical adenomatous hyperplasia and prostatic intraepithelial neoplasia. Benign small acinar lesions also may be difficult to differentiate from small acinar adenocarcinoma. An important differentiating point is the loss of basal cell layer in adenocarcinoma and its presence in benign lesions. Basal cell markers (e.g. 34βE12 cytokeratin) & proliferative markers (e.g. AgNOR and PCNA) can help in this regard. Total 60 cases of different prostatic lesions studied. After history taking, clinical examination, radiological & other investigations were done. Routine H&E staining, immunohistochemical staining against 34βE12 cytokeratin & proliferative markers (AgNOR & PCNA) was performed. Statistically significant differences found in expression of 34βE12 cytokeratin and proliferative markers between benign, premalignant and malignant prostatic lesions. Basal cell markers and proliferative markers are important parameters to distinguish between different benign, premalignant and malignant prostatic lesions.

Quantitation of conventional histologic parameters and biologic factors in prostatic needle biopsy are useful to distinguish paramalignant from malignant disease

The scope of this work was to determine the potential use of prostatic conventional histologic parameters and biologic factors in distinguishing between paramalignant and malignant prostatic disease, taking into account benign fragments of biopsies obtained from patients with prostatic cancer or from patients suspected to have cancer. Each prostate sample was semi-quantified for macronucleoli, mucin, crystalloid, collagen micronodules, and quantified for glands, stroma, AgNOR, and p53. The database covered 185 biopsy specimens from 136 patients: 56 samples from the same number of patients in whom all the biopsies were benign; 49 samples from patients whose biopsies showed malignant features, and 80 malignant samples. Discriminant analysis of the results showed statistical differences for four parameters: macronucleoli, mucin, gland volume, and AgNOR, allowing us to identify three patterns of prostate involvement: normal, paramalignant, and malignant. The discriminant function permitted an adequate classification of the three patterns in 84% of the cases. Normal areas showed glands with a mean volume of 38.93 microm3, inconspicuous nucleoli, low mucin production, and a mean AgNOR area of 1.26 microm2. Prostatic biopsies with prominent nucleoli and the presence of mucin (60%), gland volume of 22.31 microm3, and AgNOR area of 2.14 microm2 characterized the paramalignant condition. Malignant areas were characterized by mean glands with a volume of 8.11 microm3, prominent nucleoli, high mucin secretion (100%), and AgNOR area of 4.47 microm2. We concluded that modifications in prostate histoarquitecture and function, such as the presence of macronucleoli, volume of glands, abnormal secretion of acid mucin and AgNOR expression, represent important parameters that must be incorporated in the pathologist's evaluation of prostate biopsies to the purpose of indicating a subsequent biopsy, particulary in those patients with clinical suspicion of malignancy, and whose prostate biopsy specimen showed paramalignant areas.

Human prostate cancer risk factors

Prostate cancer has the highest prevalence of any nonskin cancer in the human body, with similar likelihood of neoplastic foci found within the prostates of men around the world regardless of diet, occupation, lifestyle, or other factors. Essentially all men with circulating androgens will develop microscopic prostate cancer if they live long enough. This review is a contemporary and comprehensive, literature-based analysis of the putative risk factors for human prostate cancer, and the results were presented at a multidisciplinary consensus conference held in Crystal City, Virginia, in the fall of 2002. The objectives were to evaluate known environmental factors and mechanisms of prostatic carcinogenesis and to identify existing data gaps and future research needs. The review is divided into four sections, including 1) epidemiology (endogenous factors [family history, hormones, race, aging and oxidative stress] and exogenous factors [diet, environmental agents, occupation and other factors, including lifestyle factors]); 2) animal and cell culture models for prediction of human risk (rodent models, transgenic models, mouse reconstitution models, severe combined immunodeficiency syndrome mouse models, canine models, xenograft models, and cell culture models); 3) biomarkers in prostate cancer, most of which have been tested only as predictive factors for patient outcome after treatment rather than as risk factors; and 4) genotoxic and nongenotoxic mechanisms of carcinogenesis. The authors conclude that most of the data regarding risk relies, of necessity, on epidemiologic studies, but animal and cell culture models offer promise in confirming some important findings. The current understanding of biomarkers of disease and risk factors is limited. An understanding of the risk factors for prostate cancer has practical importance for public health research and policy, genetic and nutritional education and chemoprevention, and prevention strategies.

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.

Silver-stained nucleolar organizer regions in adenocarcinoma of the cervix--a light and electron microscopic study

An increase in the number of Ag-NORs has been described as a possible marker for histopathological cancer diagnosis. The ultrastructural correlation of the reaction, however, has never been elucidated. In tissue samples of the endocervix of the uterus, we compared the ultrastructural configuration of Ag-NORs with the number of Ag-NORs dots. Light microscopic studies showed that the number of Ag-NORs in adenocarcinoma cells significantly increased, but the relation to the bromodeoxyuridine labeling index was not determined. By electron microscopy, Ag-NORs were only observed in the nucleoli and the nuclear bodies of nuclei. Ag-NORs were localized on all components of the nucleolar structure, but the dense fibrillar component was the predominant site in several cases. The nuclear bodies were exclusively found in adenocarcinoma cells and were argyrophilic. A spotted distribution of Ag-NORs was often found in the nucleoli of adenocarcinoma cells that showed an increased Ag-NOR count. The number of Ag-NORs was attributed not only to the number of nucleoli and nuclear bodies in a nucleus but also to the speckled distribution of silver deposits in a nucleolus. These results imply that the Ag-NOR count is a more definitive indicator of a hyperactive state of the cells than the combined number of nucleoli and nuclear bodies in adenocarcinoma of the uterine cervix.