Objective: To investigate differences in MMP-2 protein expression in VIN, vulvar invasive carcinoma, and lichen sclerosus, we performed an immunohistochemical study in which tissue samples from individuals affected by these conditions were compared with normal vulvar tissue.
Methods: A total of 57 cases were selected, as follows: 14 cases of vulvar invasive carcinoma, 22 of vulvar intraepithelial neoplasia (6 of VIN I, 5 of VIN II, and 11 of VIN III), 9 of vulvar lichen sclerosus, and 12 samples of normal vulvar tissue. Immunohistochemistry was done with primary monoclonal antibodies against MMP-2 and quantification of the immunostaining was done by counting the number of antigen-positive stromal cells per 1000 stromal cells.
Results: Normal vulvar tissue had a median score of 37.99 stromal cells positive for MMP-2. The median scores for VIN I/II and lichen sclerosus were 41.98 and 46.51, respectively, with no statistical differences when compared to the normal group. Invasive cancer had a score statistically higher (160.36) than any of the other groups.
Conclusion: Invasive vulvar carcinoma had a score statistically higher of MMP-2 than normal tissue, VIN, and lichen sclerosus.