Morphometric quantitation of nucleolar organizer region proteins in breast carcinoma.

Silver-stained proteins associated with nuclear organizer regions (Ag-NORs) were visualized using a standard silver staining technique in biopsy specimens from 130 breast carcinomas. The Ag-NOR protein area and perimeter (individual dots) were measured by image analysis, and the results were correlated with clinical, histologic, and quantitative prognostic factors and with survival. The mean area of Ag-NORs was related significantly to the degree of tubule formation (P = .034), histologic grade (P = .029), mean nuclear area (P = .008), SD of the nuclear area (P = .001), DNA ploidy (P = .015), S-phase fraction (P = .012), mitotic index (P = .013), and estrogen (P = .014) and progesterone receptor content (P = .001). The results of Ag-NOR morphometry were independent of tumor size and axillary lymph node status. The mean area of Ag-NORs was related to survival in the entire cohort (P = .07). In axillary lymph node-negative tumors, long Ag-NOR perimeters indicated a lower probability of survival (P = .06). However, in multivariate analysis, morphometry of Ag-NOR dots had no independent prognostic value. The results confirm previous results in that Ag-NOR protein quantitation was shown to have no practical prognostic value over already-established prognostic factors in breast carcinoma.