Value of P53, Ki-67 and CD10 in Differentiation between Keratoacanthoma and Squamous Cell Carcinoma

Purpose: Keratoacanthoma (KA) is a rapidly growing cutaneous tumor and may be difficult to distinguish from squamous cell carcinoma (SCC) on histomorphology alone. There is a major controversy over the natural behavior of keratoacanthoma. KAs have been described as benign lesions, but also as variants of squamous cell carcinoma. It is important to distinguish these neoplasms because they have different clinical behavior and different therapeutic planning. The present study aims at investigating the role of P53, Ki67, and CD10 in differentiation between KA and SCC. expresCases were collected from Pathology Department of Faculty of Medicine, Benha University, in the period 2010-2013. P53, Ki67, and CD10 immunohistochemical staining were performed in all cases and the pattern of expression was analyzed. Results: 83.3% of the examined SCC cases and 41.7% of the examined KA cases showed nuclear expression of Ki-67 antigen and this was statistically significant (p 0.05). In KA, positive cells were usually located in the basal layers at the periphery of the lesion. SCC displayed positive cells in a diffuse pattern. CD 10 immunopositivity was detected in the stroma of 100% of SCC and in 16.7% of KA cases, and these was statistically highly significant (p 0.01). Nuclear expression of P53 antigen was detected in 88.9% of examined SCC cases and in 66.7% of examined KA cases. This was a statistically insignificant correlation (p 0.05). The pattern of p53 expression was the same of Ki-67. The expression of Ki-67 was statistically significantly correlated to p53 nuclear expression and CD10 stromal expression. Conclusion: The results of this study suggest that Ki-67 and p53 have similar distribution patterns, but the former is more precise in differentiation between KA and SCC. Pattern and extent of expression of both Ki-67 and CD10 are valuable in differential diagnosis between KA and SCC. Combination between both markers (Ki-67 and CD10) will guide towards more precise differentiation.