Multiple lines of evidence have shown that perioperative opioids requirement was associated with poor outcomes in cancer patients, including increased cancer progression and metastases and reduced survival in patients with lung, breast, prostate, and bladder cancer. Circulating tumor cells (CTCs) have been validated as prognostic biomarkers of a number of cancers. The aim of this study is to investigate the effects of perioperative opioids on the number of CTCs in patients receiving robot-assisted laparoscopic radical cystectomy. The difference of the amounts of perioperative opioids is achieved by using general anesthesia combined with intravenous opioid-based analgesia intra- and post-operatively in one group and general analgesia combined with epidural ropivacaine-based analgesia in the other group.

Inclusion Criteria:

• Age >=18
• ASA I-II
• Patients with primary bladder cancer of Stage T2a or higher, who are scheduled for robot-assisted laparoscopic radical cystectomy
• Written informed consent

Exclusion Criteria:

• Emergency surgery
• Palliative surgery
• Contraindications for epidural anesthesia
• Metastatic bladder cancer
• Patients with a history of any other malignancy
• Chronic opioids medication
• severe systemic disease (heart, lung, kidney, or immune system)
• Known hypersensitivity or suspected allergy to intervention drugs
• Intellectual Disability