Erdur ZB, Özdoğan HA, Yener HM, et al. - This is the first study investigating the association between sinonasal inverted papilloma and inflammatory blood markers. Participants in the study were 65 patients who were diagnosed histologically as having sinonasal inverted papilloma and 65 age- and sex-matched healthy controls. Patient and control groups were compared with inflammatory blood markers like neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio (PLR), red cell distribution width (RDW), mean platelet volume (MPV), and platelet distribution width (PDW). No statistically significant differences were observed between the patients and controls for white blood cell, platelet, hemoglobin, neutrophil, and lymphocyte counts. There was no statistically significant difference between the patients and controls for NLR, PLR, RDW, MPV, and PDW. The findings indicate that NLR and PLR can be used to differentiate between controls and patients with sinonasal inverted papilloma.