Evaluation of three different AgNOR counting methods in advanced carcinoma of the prostate

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.

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.