Enhancement by fluphenazine of dimethylbenz[a]-anthracene-induced mammary tumorigenesis in rats.

Mammary tumor formation in female Sprague-Dawley rats was studied as a 2-stage protocol of initiation with 7,12 dimethylbenz[a]anthracene (DMBA) followed by repeated treatment with fluphenazine decanoate. No mammary tumors were found in the untreated control group or in the fluphenazine-treated groups. The repeated fluphenazine treatment was found to increase the number of mammary tumors in rats who had previously received DMBA and also to shorten the tumor latency period. The significance of these findings is discussed.