Abstract
A simple method is described by which epithelial cells can be obtained easily from well defined areas in the human bladder. During cystoscopy under direct vision epithelial cells can be aspirated through a blunt ureteral catheter from selected areas of normal-appearing mucosa and from bladder neoplasms for use in routine cytology studies and quantitative single cell measurements by flow cytometry. With this selective method of collecting cytological material pathological changes not detectable in voided urine or bladder washing specimens can be demonstrated. The method seems especially suited for tracing aneuploid cells in pre-malignant and malignant conditions, with the possibility of mapping the entire bladder mucosa for the extent of pathological changes.