Effect of partial cystectomy on the induction of pre-neoplastic lesions in rat bladder initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine followed by bladder carcinogens and promoters.

The effect of partial cystectomy on the occurrence of pre-neoplastic lesions, papillary or nodular hyperplasia (PN hyperplasia), of the bladder in male F344 rats was studied in an experiment in which bladder carcinogens and promoters were given to the rats after initiation with BBN. The bladder carcinogens tested were N-ethyl-N-(4-hydroxybutyl)nitrosamine (EHBN) and N-4[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) and the bladder promoters were sodium saccharin, sodium cyclamate, and DL-tryptophan. Partial cystectomy significantly decreased the occurrence of PN hyperplasia in rats treated with EHBN and tended to inhibit that in rats given saccharin or tryptophan. Thus partial cystectomy inhibited rather than enhanced the induction of PN hyperplasia.