Does flexible cystoscopy miss more tumours than rod-lens examination?

The first blind, prospective, randomised comparison of flexible cystoscopy with rod-lens cystoscopy was carried out on 53 consecutive volunteers with bladder tumours or haematuria. Three patients' recurrences were missed on flexible cystoscopy and 3 others on rod-lens examination. It was expected that the 9% rate of missed tumours would lessen with increased experience of flexible cystoscopy, as 2 of them occurred in the first 12 examinations and all of the lesions missed were < 5 mm in diameter. Rod-lens cystoscopy, the accuracy of which appears to have been measured for the first time, was no more sensitive.