For patients who develop oligometastatic renal cell carcinoma amenable to local therapies (i.e. ablation, radiation therapy, or surgery), how do you integrate systemic therapy, if at all?

With full disclosure that the answer to this question is in the relm of a data free zone, for patients with oligometastatic disease not on systemic therapy, the answer is of course dependent upon site of disease i.e. CNS vs bone vs liver etc. That said if the solitary site of disease is managed with some "definitive" local therapy we are in the setting of stage 4 NED, the agents we use front line are obviously toxic, thus in general I would manage the patient expectanty. For patients ON systemic therapy, typically I would change therapy, although for patients with bone predominant disease who may have been on therapy for a period of time and tolerating therapy well, I would be thoughtful about changing therapy.

I agree with @Dr. First Last. If NED otherwise, I would observe after local therapy to mets. If on systemic tx, then we will sometimes use local therapy to progressing lesions (CNS, bone for sure but sometimes even other sites with SBRT). In that case continuing systemic tx depends on the state of other disease (volume, if progressing or not, pace of progression etc.), tolerance etc, but I dont always switch immediately.