扁平上皮化生を有した巨大膀胱結石の1例

Abstract

This report deals with a case of giant calculus arising in the urinary bladder of a 55-year-old male, who had a history of lower abdominal discomfort for a few years. The calculus was measured 810g in weight, and this was the third big one in our country. Histological finding of the vesical mucosa was compatible with squamous metaplasia. One year later, cystoscopic examination revealed a small grayish-white and sharply demarcated plaque, which was evaluated to be leukoplakia of the urinary bladder by transurethral biopsy. The pathogenesis of this squamous metaplasia and leukoplakia seems to be closely related to longstanding urinary infection usually associated with calculi. Histological examination of yesical mucosa at the time of cystolithotomy was recommended, because such mucosa is considered to have a tendency of transformation to squamous metaplasia, leukoplakia and rarely epidermoid cancer.