[Mucin histochemical analysis of mucin-forming carcinomas, metaplasias of the urothelium and in persistent urachus].

Twelve cases of mucus secreting metaplasias, nine mucus secreting urothelial carcinomas and three cases of urachus remnants were studied using D-PAS-, m-PAS,- AB pH 2,5/PAS-, HID/AB pH 2,5- and PB/KOH/PAS-technique. Neutral mucins, sialomucins, sulfomucins, O-acylated and unsubstituted or C4- and C7-substituted mucins were detected in different quantities, often intracellular mucus mixtures could be seen. Many differences in the mucus quality of the metaplasias, in comparison to that of the tumors, were not noticeable. Metaplasia associated with carcinoma and mucus secreting carcinomas showed a loss of O-acylated sialomucins and besides diffus positive reaction in m-PAS-technique. Further investigations should confirm if this is really a prognostic factor. O-acylated sialomucins were not only found in metaplastic lesions and urothelial carcinomas but also in metaplasias of the urachus. Therefore it is not possible to distinguish between adenocarcinomas of the urinary bladder and adenocarcinomas derived from the Urachus using PB/KOH/PAS method.