Experimental colonic tumours in the rat. II. Double contrast examination and microscopy.

Experimentally induced tumours in the colon of the rats were examined with a double contrast method. Carcinogenic agents were administered to 114 rats. The development of the colonic tumors was recorded by repeated examinations. In the dead rats a thorough necropsy was performed. The radiographic and microscopic results were correlated and the radiographic appearances of colonic tumours were evaluated. The diagnostic accuracy of the radiographic method in distinguishing between benign and malignant lesions was 92 per cent.