I noticed none of the articles ever said it was cancer-- only said waiting on pathology, and he may need the other kidney operated on later. This sounds like it might be a pheochromocytoma, a tumor of the adrenal gland. This may explain his vertigo and orthostatic hypotension (almost fainting when standing up from a sitting position), which are common symptoms of a pheo. Good news is that pheochromocytomas (if that's what it is) are rarely malignant.

Best wishes to 'Ol Roy. Speedy recovery!