Quantification of the argyrophilic nucleolar organizer regions (
AgNORs), using a one-step
silver colloid method, was made in proliferative urothelial lesions including
neoplasm of the rat urinary bladder induced by 0.05% N-butyl-N-(4-hydroxybutyl)
nitrosamine (BBN) and of the human urinary bladder. The mean numbers of
AgNORs in various experimental lesions in rats given BBN for 5-30 weeks in
drinking water were: nontreated urothelium (n = 6), 1.26 +/- 0.09; urothelium outside focal lesions (n = 10), 1.75 +/- 0.10; simple
hyperplasia (n = 10), 2.01 +/- 0.15; papillary or nodular (PN)
hyperplasia (n = 10), 2.15 +/- 0.19;
papilloma (n = 5), 2.37 +/- 0.12; and
transitional cell carcinoma (TCC) (n = 5), 3.52 +/- 0.23. There was a significant difference in the mean number of
AgNORs between any two groups (p less than 0.05), except for simple
hyperplasia vs PN
hyperplasia (p = 0.085). In various proliferative lesions of human biopsy and resected samples, the mean numbers of
AgNORs were normal urothelium (n = 8), 1.71 +/- 0.08; proliferative
cystitis (n = 14), 1.79 +/- 0.18;
hyperplasia (n = 8), 1.76 +/- 0.23; mild dysplasia (n = 5), 2.15 +/- 0.36; moderate dysplasia (n = 13), 2.61 +/- 0.27; severe dysplasia (n = 6), 3.46 +/- 0.57; G0 of TCC (n = 9), 1.95 +/- 0.17; G1 of TCC (n = 16), 2.39 +/- 0.20; G2 of TCC (n = 21), 3.33 +/- 0.31; G3 of TCC (n = 15), 4.68 +/- 0.51; and
carcinoma in situ of TCC (n = 10), 3.61 +/- 0.52.(ABSTRACT TRUNCATED AT 250 WORDS)