[Emulsifiers which reduce the latency of the development of colonic cancer--sodium lauryl sulfate and methylazoxymethanol].

The effect of emulsifier (nonionic surfactant) on the production of adenocarcinoma by methylazoxymethanol acetate in the large intestine of rats was studied. Following emulsifier, sodium lauryl sulfate administration, many cases of undifferentiated adenocarcinoma consisting of anaplastic glandular cells were induced in the experimental groups. Lymphatic invasion by cancer cells was found in 3 cases and metastasized to other organs in 6 cases. On the contrary, the control group (administered methylazoxymethanol acetate only) revealed well-differentiated adenocarcinoma in many cases. This fact may be due to an emulsifier used as a vehicle for the chemical, and the emulsifier might activate the character of promotion to carcinogenisity as a secondary agent. By virtue of the strong penetrating property of the emulsifier, colonial carcinogenesis seems to be enhanced.