Abstract:Objective To investigate the expression of squamous cell carcinoma antigen (SCCA) on chronic rhinosinusitis with nasal polyps (CRSwNP) patients and its application value in the endotype of nasal polyps. Methods Seventy-four patients with CRSwNP and 40 healthy volunteers were enrolled in research. CRSwNP was divided into non-eCRSwNP group (n=33) and eCRSwNP(n=41) according to the tissue eosinophil ratio. The peripheral blood of the enrolled patients was collected before surgery to detect the serum concentration of SCCA, and we explored the correlation between SCCA and clinical indicators and the difference of SCCA concentration between patients with different endotype. Results Compared with the control group, the serum SCCA expression level in CRSwNP group was significantly increased (P < 0.0001). Compared with the non-eCRSwNP group, the serum SCCA expression level was significantly increased in the eCRSwNP group (P < 0.0001). Serum SCCA concentration in CRSwNP patients was positively correlated with eosinophil count in peripheral blood (r=0.404, P=0.0004) and tissue eosinophil ratio (r=0. 283, P=0.015). Binary logistic regression and ROC analysis indicated that the serum SCCA level was significantly correlated with CRSwNP tissue endotype (AUC=0.844, P=0.000). Conclusion Serum SCCA expression in CRSwNP patients is up-regulated and associated with tissue eosinophilic inflammation. The expression level of SCCA may be helpful for the preoperative identification of CRSwNP endotype.