To resolve this issue, cellular and molecular distribution patterns in surgically resected nasal polyps from CRSwNP patients, such as mast cells,7 transforming growth factor β1 (TGF‐β1),8 and periostin,9 which are suspected to be important in the formation of nasal polyps under CRS, were histologically examined. The gene discussed is TGFB1; the disease is chronic rhinosinusitis with nasal polyps.