Colonic metaplasia in the long-term follow-up of the ileal neobladder

OBJECTIVE: To look for the presence of colonic metaplasia (CM), the shifting from sialomucins (SIs) to sulfomucins (SUs), considered as a probably premalignant lesion in the stomach in the mucosa of the ileal neobladder (IN). METHODS: 19 patients with IN were subjected to endoscopic biopsy; the samples were analyzed by means of histochemistry with high iron diamine, a test indicated to identify SIs and SUs. RESULTS: CM was never observed earlier than 1 year after the operation, was absent in 9/19 patients (mean follow-up 14 months) and present in 10/19 (mean follow-up 59 months). CONCLUSION: Time-dependent phenotypic changes, already described in the stomach as being premalignant, take place after constant contact with urine in the mucosa of the IN. It is at present unclear whether they may be defíned as only metaplastic or frankly preneoplastic; anyway, a careful follow-up remains indicated in all patients with íntestinal urinary diversions.