FGF23 and neoplasm: This concept is further supported by studies showing that the acute reductions in FGF23 that follow tumor resection in TIO correlate with a rapid rise in 1,25(OH)2D to above‐normal levels followed by normalization.94 Likewise, other strategies to block FGF23 action, including ERK inhibition and pan‐FGFR inhibition, also acutely raise 1,25(OH)2D levels above normal in hypophosphatemic (hyp) mice followed by normalization.95, 96