Foreign-body tumorigenesis by vinyl chloride vinyl acetate copolymer: no evidence for chemical cocarcinogenesis.

We investigated whether vinyl chloride monomers, released from implants of vinyl chloride vinyl acetate copolymer (VCA), exerted cocarcinogenic activity and added thereby to the mechanism of foreign-body (FB) tumorigenesis. CBA/H and CBA/H-T6 mice were used. No evidence was found to indicate that chemical carcinogenic activity partakes in tumorigenesis by VCA implants. Hence it was concluded that VCA plastic is not suitable for the study of the combined process of FB/chemical cocarcinogenesis. Furthermore, experimental results obtained with VCA film implants were representative of FB tumorigenesis in the absence of demonstrable chemical carcinogenic activity.