Study of Optimized Management of Nivolumab Based on Response in Patients With Advanced RCC (OMNIVORE Study)

* Age ≥ 18 years at the time of consent. * ECOG Performance Status of ≤ 2 within 28 days prior to registration. * Unresectable advanced or metastatic RCC to include both clear cell and non-clear histologies. oPatients who have suspected metastatic RCC, which has not yet been pathologically proven, may be enrolled if they plan to undergo a cytoreductive nephrectomy, metastectomy, or biopsy. Fresh tissue from one of these procedures can be used for the clinical trial requirements (eligibility #4) as well as serve as pathologic confirmation of RCC. The pathologic confirmation must be documented prior to C1D1. * Availability at the study site of formalin-fixed, paraffin-embedded (FFPE) archival tumor specimens, when available, and willingness of the subject to undergo mandatory fresh tumor biopsy prior to treatment initiation unless determined medically unsafe or not feasible. If a target lesion is biopsied at screening, this lesion must be followed as non-target lesion after the biopsy unless it is the patient's only target lesion. If there is only one target lesion, it should be followed as a target lesion regardless. * The archival specimen must contain adequate viable tumor tissue. * The specimen may consist of a tissue block (preferred and should contain the highest grade of tumor) or at least 30 unstained serial sections. Fine-needle aspiration, brushings, cell pellet from pleural effusion, bone marrow aspirate/biopsy are not acceptable. * Previously untreated or tre…