Polyps at the site of ureterosigmoidostomy

Anatomoclinical findings in 6 patients under long-term control of ureterosigmoidostomy, performed 5 to 26 years previously for nonneoplastic bladder pathology, are reported. Four histologically confirmed polyps are described and histopathogenetic theories are discussed. The authors suggest that these polyps arise from the ureter via glandular metaplasia due to external contact surgically created in urinary diversion.