Abstract
BACKGROUND: Verrucous carcinoma (VC) are always considered to be a variant of well-differentiated squamous cell carcinoma (SCC). If Keratoacanthoma (KA) is a variant of well-differentiated SCC, it is controversial currently. Both β-catenin and Wnt5a are key factors in the classical and non-classical Wnt signaling pathways, which are often used in the differential diagnosis of benign and malignant tumors. However, the expression of these two factors in these three diseases remains unclear. The goal of the current study was to explore the expression of β-catenin and Wnt5a in KA, VC, and well-differentiated SCC and to determine their value in differential diagnosis. METHODS: Twenty samples were collected from VC lesions, 30 from KA lesions, and 30 from cutaneous well-differentiated SCC lesions. The expression of Wnt5a and β-catenin in paraffin-embedded tissue sections was analyzed by immunohistochemistry. The histo (H) score was used to evaluate positive cases. RESULTS: There were no statistically significant differences in sex or age between KA, VC, and well-differentiated SCC patients (P-value>0.05). Immunohistochemical analysis showed that β-catenin was expressed in all tissues. For Wnt5a and β-catenin staining intensity, H score and H-score category, there were significant differences between the well-differentiated SCC and KA groups, as well as VC and KA groups (P-value<0.01 for all). However, there were no differences between the well-differentiated SCC and VC groups (P-value>0.05). CONCLUSION: In this study, the differential expression of Wnt5a and β-catenin suggests that the benign tumor KA and well-differentiated SCC may be two distinct entities. We identified that Wnt5a and β-catenin could be used as adjuvant immunohistochemical markers for the differential diagnosis of KA from well-differentiated SCC.