Specifics of type IV collagen expression in basal cell skin carcinoma

Rationale: Type IV collagen is the main component of the basal membrane ensuring its integrity. Basal membrane destruction is associated with absent type IV collagen expression being directly related to an increased tumor invasion risk. Specifics of the protein expression in various morphological types of basal cell carcinoma have not been well described. Aim: To study the association between type IV collagen expression and basal cell carcinoma morphological structure and invasion potential. Materials and methods: We performed an immunohistochemistry analysis with anti-type IV collagen antibodies on 30 biopsy specimens of the skin involved with basal cell carcinoma. Results: The superficial multicentric type of basal cell carcinoma differed from the solid, micronodular, and infiltrative types by linear continuous type IV collagen expression (р < 0.0083). Most often, there was no type IV collagen expression in the micronodular and infiltrative basal cell carcinomas; however, no significant difference of the solid type and each of the abovementioned types was found. Aggressive basal cell carcinoma types (micronodular and infiltrative, taken together) were significantly different (р = 0.033) from the solid type by the absence of type IV collagen expression. Linear continuous expression was seen exclusively in basal cell carcinomas with the invasion of < 0.825 mm. Conclusion: We have identified the difference in type IV collagen expression depending on the morphological type of basal cell skin carcinoma, prevailing linear continuous expression in the superficial multicentric type and its absence in the micronodular and infiltrative types.