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Superficial bladder cancer: for how long should a tumour-free patient have check cystoscopies?

OBJECTIVE
To determine the probability of a patient with superficial bladder cancer developing a recurrent tumour after having remained tumour free for 2 or more years.


PATIENTS AND METHODS
One-hundred and seventy-nine patients with Ta or T1 tumours at diagnosis, a minimum follow-up of 3 years and a minimum of 2 years remaining tumour free were identified. Thirteen patients had more than one episode that was eligible for inclusion and there were therefore 192 tumour-free episodes for analysis. Survival curves of the probability of being recurrence-free against time were constructed for the whole group, for subgroups of Ta and T1 tumours and for subgroups with characteristics at diagnosis suggesting a good, intermediate and poor prognosis.


RESULTS
The probability of a patient developing a recurrence after 2, 5 and 10 years of being tumour free was 43, 22 and 2% respectively. No patient had a recurrence after remaining tumour free for 12 years. No patient who had been tumour free for at least 2 years progressed to muscle invasion or metastases. There was no significant difference in the probability of recurrence between Ta and T1 tumours after 2 years of remaining tumour free.


CONCLUSION
The optimum length of cystoscopic follow-up for patients with superficial bladder cancer is unknown, but patients continue to develop recurrences even after many years of being tumour free. If a patient is to discontinue cystoscopic follow-up, then alternative methods of assessment should be applied.