Recently, in an experiment designed to study the effects of the intraoral application of tobacco tar as a carcinogenic agent in mice, Holsti and Ermala observed that about 75% of the mice developed urinary bladder papillomas in contrast to none of the control group and that 10% of the experimental group had papillomas that were histologically malignant.1 It would be of considerable interest to determine if in humans a similar relationship exists. As a first approach to the study of such a relationship, the clinical records of patients admitted to the Roswell Park Memorial Institute were reviewed. This is a report of the results of this analysis.
Method of Study
The method of study consisted of a comparison of the histories of tobacco use of a group of patients with urinary bladder cancer with those of patients with other cancers and noncancerous conditions. The other cancers selected for study