Cystoscopy follow-up should be conducted for around 10–15 tumor-free years after BCG treatment, according to a new retrospective study. Based on data from 542 patients, the risk of recurrence after 10 years and 15 years was 12.5% and 20.5%, respectively. Additionally, recurrences were 8.5 times more common after a tumor-free period of 5 years for patients who had recurrent tumors before BCG treatment.