Could a more extensive surgery keep kidney cancer from coming back?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Signed informed consent form. * Age \> 18 years. * Candidate for radical nephrectomy with or without lymph node dissection. * High-risk renal cell carcinoma defined as: At least ONE of: Clinical stage cT3-4 N0-1 M0 (AJCC 8th ed); OR radiologically visible lymph node \>1cm; OR M1 disease rendered no evidence of disease (NED) after local therapy; OR radiologically determined rT4 stage. OR at least TWO of: Renal vein or inferior vena cava tumor thrombus; OR nuclear grade 3-4 or sarcomatoid differentiation or coagulative necrosis; OR tumor size \>= 10cm; OR hematuria and/or local symptoms. * Measurable disease as per RECIST v1.1. * ECOG performance status of 0 or 1. * Adequate bone marrow, renal, and hepatic function. * For women and men of childbearing potential, agreement to use effective contraception during the study period. Exclusion Criteria: * Prior radiotherapy, chemotherapy, major surgery, or targeted therapy for RCC. * Concurrent other active malignancy (except controlled malignancies not affecting 2-year survival). * Candidate for partial nephrectomy or ablation per multidisciplinary team assessment. * Preoperative imaging indicates unresectable regional lymph nodes. * renal tumors or known hereditary RCC syndrome. * Diagnosis of any other active malignancy within the past 5 years. * Active autoimmune disease or history of autoimmune disease. * Use of immunosuppressive agents within 2 weeks prior to enrollment. * Poorly controlled cardiac or clinical symptoms. * Coagulopathy or bleeding tendency. * Active gastrointestinal conditions with risk of bleeding or perforation. * History of significant bleeding or thromboembolic events within specified timeframes. * Active infection or unexplained fever \>38.5°C. * Abdominal fistula, gastrointestinal perforation, or abscess within 4 weeks prior. * History of pulmonary fibrosis, interstitial lung disease, or severely impaired pulmonary function. * Known immunodeficiency or active hepatitis. * Participation in another clinical trial within 1 month. * Known history of drug abuse or alcohol addiction. * Inability or unwillingness to bear the self-paid portion of examination and treatment costs. * Any condition that, in the investigator's judgment, may compromise patient safety or study conduct.