iarmsIARMSIARMS2709-3255https://doi.org/10.47310/iarms.2021.v02i01.008Evaluation of Immunohistochemical Expression of Cyclin D1 (Bcl-1) and Ki-67 antigen (MIB-1) in Cutaneous Basal Cell Carcinoma and Adjacent EpidermisVladimírBartošMD, PhD, Master of Public Health, Martin´s Biopsy Center, Prieložtek, Martin, SlovakiaBackground: The Ki-67 antigen and the D-type cyclins play a key role in the cell cycle regulation. Objective: The goal of this study was to evaluate an immunohistochemical expression status of Cyclin D1 and Ki-67 in basal cell carcinoma (BCC) of the skin and to find out whether there is a correlation between them. Material and Methods: The study included biopsy specimens from 29 BCCs, which were immunohistochemically stained for Cyclin D1 and Ki-67. The cases were graded on a semiquantitative scale based on the average proportion of immunoreactive cells: 0 (<1%), 1+ (1-10%), 2+ (11-50%) and 3+ (>50%). Results: All BCCs were positive for both proteins. As for Cyclin D1, the grades 1+, 2+ and 3+ were found in 4 cases (13.8%), 18 cases (62.1%) and 7 cases (24.1%). As for Ki-67, the grades 1+, 2+ and 3+ were found in 1 case (3.4%), 18 cases (62.1%) and 10 cases (34.5%). In adjacent epidermis, all cases exhibited a mild degree of Cyclin D1 and Ki-67 immunoreactivity. Comparing both markers, there were 22 BCCs (75.9%) showing the same semiquantitative grade of Ki-67 and Cyclin D1 expression and 7 BCCs (24.1%), in which Ki-67 grade was one degree higher than Cyclin D1 grade. Conclusion: All BCCs expressed Cyclin D1 and Ki-67 that were more pronounced in tumor tissue than in adjacent normal epidermis. This indicates, both markers play a role in the carcinogenesis of cutaneous BCC. The expression of Cyclin D1 appeared to have a positive correlation with Ki-67 expression, suggesting the production of Cyclin D1 protein is directly related to cell proliferation.