Immunohistochemical Expressions of Ki-67, Cyclin A, p53, and p16 in Actinic Keratosis, Bowen's Disease and Squamous Cell Carcinoma

Lee, Hyo Jin; Shin, Dong Hoon; Choi, Jong Soo; Kim, Ki Hong

Abstract

BACKGROUND
Actinic keratosis (AK) and bowen's disease (BD) are pre-cancerous diseases, and are regarded as an early squamous cell carcinoma (SCC). AK and BD can be progressed into SCC. In this process, tumor suppressor and cell proliferative proteins may play important roles.
OBJECTIVE
To investigate the differences of expression patterns of the immunohistochemical (IHC) staining and useful markers for differential diagnosis in AK, BD and SCC.
METHODS
Biopsy had proven 17 cases of AK, 20 cases of BD and 17 cases of SCC, which were all selected. IHC staining for Ki-67 and cyclin-A, as cell proliferative markers, p53 and p16 as tumor suppressor markers, were performed. Labeling index (LI) and distribution pattern of IHC expressions were measured.
RESULTS
LI of Ki-67 in AK, BD and SCC were 30.6%, 60.2% and 54.8%, respectively. LI of cyclin-A in AK, BD and SCC were 9.2%, 24.4% and 24.1%, respectively. LI of p53 in AK, BD and SCC were 20.7%, 37.9%, and 39.9%, respectively. LI of p16 in AK, BD and SCC were 10.6%, 38.3% and 39.9%, respectively. Lower 1/3 was the most frequent distribution pattern in AK in all IHC stains, full thickness lower 2/3 were the most frequent distribution pattern in BD and SCC in all IHC stains.
CONCLUSION
LI and distribution pattern of Ki-67, cyclin-A, and p16, as well as the distribution pattern of p53 may be useful markers to differentiate AK from BD and SCC. Higher degree and full-thickness distribution pattern of IHC expressions in all stains may be helpful in the diagnosis of BD, rather than AK.