Histologic, histometric and histochemical parameters in differentiation of keratoacanthoma from keratocarcinoma [KARATOAKANTOM-EPIDERMOID KARSINOM AYIRICI TANISINDA HISTOLOJIK, HISTOMETRIK VE HISTOKIMYASAL PARAMETRELER]

Keratoacanthoma is a common skin tumor seen in elderly people with fair a complexion in their sun-exposed skin areas. It can be considered as an abortive malignancy which rarely transforms into an invasive squamous carcinoma. In this study 105 cases of keratoacantoma (KA) and 13 cases of keratocarcinoma (KCa) diagnosed between the years 1981 and 1994 at our department have been reexamined in light of recent views. Selected cases (11 cases) of squamous cell carcinoma (SCC) have also been included into the study. It was found that KCa cases had a number of features which proved to be significant in differentiating from KA including; prominent cellular atypia pleomorphism high mitotic rate decreased glassy cells increased proliferative activity in basal layer, absence of granular layer parakeratosis and plasma cells in margins of the lesion. Staining results with peanut agglutinin however was found to be not much helpful in differential diagnosis.