ECRSwNP is a distinct phenotype of CRSwNP, with many significantly different clinical features from non-ECRSwNP. Immunohistology is a reliable way to present the subtypes; however, the results mainly depend on the pathologist’s observation, and the method with automatic readout and the corresponding biomarkers is lacking.

The purpose of our research was to explore the predictive value of qRT-PCR as an alternative method and mRNA expression of CLC as a corresponding target for ECRSwNP, which may benefit the automatized judgment.

Researchers evaluated CLC mRNA levels in tissue samples from 48 CRSwNP patients and ten controls by quantitative real-time PCR. mRNA level of CLC in ECRSwNP was significantly elevated compared to either the non-ECRSwNP group or the control group, with no significant difference between non-ECRSwNP patients and controls. Logistic regression analysis revealed CLC mRNA level, and blood eosinophil percentages were prediagnosis factors for ECRSwNP. ROC curves analysis indicated the AUC of CLC mRNA level was 0.948, which was superior to the blood eosinophil percentage as an optimal biomarker to predict ECRSwNP.

The study concluded that CLC mRNA levels based on the qRT-PCR might serve as a reliable and alternative method for the identification of ECRSwNP.