Comparative analysis of immunohistochemical features in basal cell carcinoma subtypes

Background: There has been no general agreement in classifying basal cell carcinoma (BCC), and little is known about the immunohistochemical profiles in each subtypes of BCC. BCC is a locally-invasive tumor, but its aggressive forms tend to recur and metastasize. Objective: In this study, we have compared the histolopathological subtypes of BCC by immunohistochemical study. We also focused on identifying representative markers of growth in the aggressive forms of BCC by assessing VEGF, p53 and α-SMA expression. Methods: A total of 87 BCC specimens were collected at the 7 branch hospitals of The Catholic University of Korea from July 1997 to June 2003. For multiple immunohistochemical staining, a tissue microarray technique was used. The 87 samples were divided into 6 subtypes: 18 nodular, 19 nodular infiltrative, 12 micronodular, 14 infiltrative, 11 morphea and 13 basosquamous. Overall, 18 samples were classified as non-aggressive and the remaining 69 as aggressive. Results: The following results were obtained after immunohistochemical staining with antibodies α-SMA, VEGF and p53. A significant increase of α-SMA expression was observed in aggressive forms of BCC, whereas the expression of p53, VEGF, the number of mast cells remained the same. The representative markers of tumor growth such as α-SMA were most highly expressed in the basosquamous type, and least expressed in the micronodular type compared to the nodular type. Conclusion: α-SMA was considered as an appropriate immunohistochemical marker in BCC to represent aggressiveness.