I. Why bladder tumors are easy to recur The easy recurrence characteristics of bladder tumors are mainly determined by their histological characteristics. On the one hand, the most common tissue type of bladder tumor is uroepithelial cell carcinoma, which is easy to recur although its malignant degree is low. On the other hand, non-muscle invasive uroepithelial cell carcinoma accounts for 75%~85%, and muscle invasive accounts for 15%~25%. The former mostly requires minimally invasive surgery of transurethral cystectomy of bladder tumors, which is the least traumatic for patients, but about half of the patients will recur within 1 year, and 80% of the patients will recur within 5 years after surgery. Therefore, it is important to perform regular cystoscopy to monitor the recurrence of bladder lesions. At the same time, the development of a correct treatment plan based on the depth of bladder tumor invasion is the key to preventing bladder tumor recurrence. Among them, transurethral cystectomy is the main treatment for non-muscle invasive bladder uroepithelial cancer; while radical cystectomy with pelvic lymph node dissection is the standard treatment for muscle invasive bladder cancer, which is an effective treatment to improve the survival rate of patients with invasive bladder cancer and avoid local recurrence and distant metastasis. To prevent bladder cancer recurrence, it is necessary to cooperate with doctors to do the following follow-up work: make a scientific follow-up plan according to the stage of bladder tumor and the treatment method adopted. Stop smoking and avoid exposure to other carcinogens, including aniline dyes. Eat more digestible and nutritious food after surgery, and avoid spicy and irritating food. Drink plenty of water after surgery. All patients should be followed up with cystoscopy as the primary means of early diagnosis of recurrence. Recurrence is not scary; what is scary is failing to detect recurrence at an early stage and allowing the tumor to infiltrate the muscularis propria or metastasize to the extent that open resection of the bladder is required and quality of life or even life is severely compromised. The time of cystoscopy depends on the tumor grading and staging, usually receiving the first review 3 months after surgery, followed by every 3 months thereafter, every 6 months starting from the third year, and every year starting from the fifth year. Postoperative bladder instillation medication is administered strictly according to the doctor’s requirements to reduce and delay tumor recurrence. The recommendation is 1 time per week for 8 weeks, then 1 time per month for 8 months. For patients with intermediate-risk and high-risk non-muscle invasive bladder tumors, regular body cavity bladder thermotherapy is required to further reduce bladder tumor recurrence. This is 1 time per month for 3 consecutive sessions, then 1 time every 2-3 months for 3 consecutive sessions, and finally every 6 months for 2 consecutive sessions, for a total of 6-8 sessions.