AGNOR EVALUATION BY IMAGE-PROCESSING METHODS STAINING MODIFICATIONS AND RESULTS IN 126 INVASIVE DUCTAL BREAST CARCINOMAS

OBJECTIVE: To analyze cellular proliferating activity in breast cancer by means of a silver (Ag) method (AgNOR) that stains the nucleolar or ganizer regions (NORs), structures involved in protein transcription. STUDY DESIGN: We analyzed 126 invasive ductal carcinomas and we descri bed: (1) staining modifications aimed at improving the silver method, (2) AgNOR quantitative variables obtained by image processing methods, and (3) the existing relationship between these AgNOR variables and o ther established breast prognostic factors, such as Scarf-Bloom-Richar dson (SBR) grading, tumor size, axillary status, DNA index, and estrog en and progesterone receptors. RESULTS: All quantitative variables bas ed on the AgNOR area showed statistically significant differences with reference to axillary status, tumor size and SBR grading. Cluster ana lysis based on these variables allowed us to detect two proliferation- level groups of breast carcinoma, one with a low and the other with a high proliferation level. Principal component analysis provided an AgN OR-independent component (first component) unrelated to other prognost ic factors. CONCLUSION: Cellular proliferation assessed by AgNOR quant ification provides information that may improve prognostic prediction in breast carcinoma.