Would you offer RT to a large infiltrative renal metastasis in a patient with minimal other systemic disease?

With modern treatment delivery techniques, there really are no longer any regions in the body in which a potentially therapeutic dose of radiation cannot be delivered, and durable local control can be achieved in locations where this was not possible in the past. Nevertheless, as the question implies, there are a number of factors that must be considered before this type of treatment is undertaken. For example, in a situation as proposed here, one could sacrifice a kidney if the remaining one fu...

If patient is oligometastatic, I think renal SABR is a reasonable option, and there does not appear to be a location restriction (i.e. central close to hilum vs. more peripheral) based on the experience of the IROCK individual patient meta-analysis of >200 patients.

Siva S, Cancer. 2018 Mar 1;124(5):934-942.

Anecdotally, we have treated larger targets even up to 15 cm, but dial back the dose and compromise PTV to achieve OAR dose tolerance (often small bowel/duodenum), using a rx as high as 35/5#...