Lateral Prostate Capsule Sparing Versus Non Nerve Sparing Robot-assisted Radical Cystectomy-orthotopic Ileal Neobladder for Bladder Cancer in the Male

Inclusion Criteria: 1. Male patients aged 18 or older. 2. Patients those who are diagnosed with urothelial carcinoma. 3. Patients those who are without tumour in the bladder neck or urethra, and prostate cancer was ruled out by MRI and serum T-PSA\<2.5ng/ml. 4. Patients those who are capable of receiving radical cystectomy with orthotopic ileal neobladder. 5. Patients those who are able to cooperate and complete the follow-up. 6. Patients those who volunteer to participate in this study and sign the informed consens. Exclusion Criteria: 1. Patients thsoe who are diagnosed distant metastasis before surgery. 2. Patients those who are diagnosed with other malignancies. 3. Patients those who had received pelvic radiotherapy or major pelvic operation.