Effect of haloperidol on the development of the solid Ehrlich tumor in mice

We determined the effect of 13 days of treatment with 2.0 mg/kg haloperidol (s.c) on the development of the Ehrlich solid carcinoma, after inoculation of 1.5 x 10(6) Ehrlich ascites tumor cells into the left footpad of mice. The footpad thickness of haloperidol treated animals was significantly smaller than control from day two after tumor inoculation, to the end of the experiment. Histopathological examination showed that haloperidol treated mice apparently presented less necrotic areas within the tumor mass as well as less invasion of subepithelial connective tissue and other adjacent structures. In particular, in comparison with the control group, no nerve bundles were invaded by neoplastic cells in experimental mice. The possible mechanism underlying these results is discussed in light of the specific pharmacological properties of this neuroleptics drug.