Roentgenological features in villous papilloma of the colon and rectum.

With good technique it is possible to detect small polyps in the large intestine with a barium enema examination. The radiological appearences and visibility of villous papillomas in 84 barium enema examinations from patients with both benign and malignant villous papillomas in the rectum, rectosigmoideal junction and the sigmoid loop were studied. In 75% of the examinations the tumour was visible. A specific radiological diagnosis of non invasive villous papilloma was made in 33% and the correct malignant diagnosis in 8/13 cases. There were both false positive and false negative diagnoses of malignancy. Patients with a villous papilloma should undergo barium enema study with double contrast technique of the whole large intestine. Benign looking tumours can always have islands of invasive carcinoma. But the criteria for malignancy are more reliable than the diagnostic signs for the villous papilloma.