[Experimental carcinogenesis in the urinary bladder against a background of Freund adjuvant and levamisole...

Administration of complete Freund's adjuvant (CFA) to rats before carcinogenesis and in its early period was associated with an increase (not less than 2-fold) in the number of spindle-shaped dark cells that permeated the hyperplastic urothelium and, judging the ultrastructure, had a macrophage nature. These animals demonstrated a relationship between the increased number of dark cells and delayed development of the subsequent stage of carcinogenesis--papillomatous hyperplasia. CFA administration to the animals with a developed cancer of the urinary bladder did not affect it noticeably. It did not produce any effect on subcutaneous transplantation of cancer that had taken in 100% of cases. No morphological features of carcinogenesis were recorded either after levamisol administration. However, none of the tumours withdrawn from the rats given levamisol took under the skin of the recipients.