CRP and Iron deficiency anemia: NCCN guidelines recommend both IV and oral iron monotherapy for patients with absolute iron deficiency, defined as TSAT ≤20% and serum ferritin <30 ng/mL [3], whereas ESMO guidelines recommend oral iron only for patients with serum ferritin <30 ng/mL and no evidence of inflammation (C-reactive protein <5 mg/L) [2].