CRP and neoplasm: Similarly, in patients with mRCC treated with nivolumab, CRP kinetics predict greater tumor shrinkage and progression free survival (PFS), with the greatest response seen in the subset of people who experience a “CRP-flare” (initial CRP doubling with decline to below baseline level within three months) after administration of nivolumab (13) CRP kinetics have been especially well validated in response to nivolumab and sunitinib, but have also been directly validated in axitinib, IL-2, sorafenib, and surgical approaches.