T1 bladder tumours.

167 patients with T1 bladder transitional cell tumours treated by transurethral resection or cystodiathermy are reviewed. The overall crude survival was 83.2% in 3 years and 71.8% in 5 years. 7.8% of the patients developed an invasive tumour and these patients had an unfavourable initial tumour with moderate or poor differentiation and high or moderate mitotic rate. High or moderate pleomorphism was particularly unfavourable. Multiple tumours did as well as single ones but more of them had invasion of the lamina propria and a larger number were treated by either radiotherapy or cystectomy.