Carcinogenic risk estimation

Mechanistic considerations for carcinogenic risk estimation: chloroform.

Chloroform has been reported to induce cancer in rodents after chronic administration of high doses by gavage. However, the interpretation of these findings is hampered by a lack of knowledge concerning the relative roles of genetic and nongenetic mechanisms in these bioassays. The present studies were carried out in male B6C3F1 mice in order to investigate the potential of chloroform to induce...

Models for carcinogenic risk assessment.

approach is the recognition that the response to a carcinogenic agent depends on the rate of exposure. For the radioactive agents the priority for the study of the so-called dose-rate effects appears to belong to Upton (3). A review (4) indicates that important dose-rate effects exist also for certain chemical carcinogens. Another item that I miss in Comnfield's approach is the phenomenon of sy...

Transgeneration transmission of carcinogenic risk.

Introduction Molecular analysis of human tumors suggests that multiple genetic changes are required for a normal cell to become malignant (1). The multistage nature of carcinogenesis implies that cells which contain one or a few genetic mutations may behave normally; several other genetic insults are required to confer the tumor phenotype. It can be postulated that genetic damage may occur in g...

Tamoxifen therapy and carcinogenic risk.

It is quite remarkable that tamoxifen, a drug that is so effective in the treatment of breast cancer, should have so low a toxicity profile. Since 1971, tamoxifen has been used to treat many millions of patients for periods sometimes in excess of 10 years, in doses sometimes eightfold higher than the usual dose; yet the incidence of serious toxic effects from tamoxifen has been almost negligibl...

Models for carcinogenic risk assessment.