Pulmonary adenomas in A/J mice treated with silica

This study was designed to test the pulmonary tumor response to intratracheally instilled silica in Strain A mice. Urethane was used as a positive control. Silica treatment was utilized to evaluate the effect of a potent fibrinogen on pulmonary adenoma formation in this unique animal model. Urethane produced an increase in pulmonary tumor response in this study in agreement with previous investigations. Also, the background incidence of adenomas was comparable to other studies. Silica treatment did not affect tumor incidence either in terms of percent of mice with adenomas or average number of adenomas per mouse.