In a mayo clinic study of 78 patients with keratinizing squamous metaplasia ( leukoplakia ) of urinary bladder , a total of 42 % of patients had concurrent or subsequent carcinoma of the bladder . benson rc , swanson rk , farrow gm 在梅欧医院{美}的研究中， 78例膀胱角化性鳞状上皮化生病人中，有42同时合并或以后发展成为膀胱癌。
