The Determination of prevalence of seborrheic keratosis related premalign skin tumors and their clinicopathological features

ABSTRACT THE DETERMINATION OF PREVALENCE OF SEBORRHEIC KERATOSIS RELATED PREMALIGN AND MALIGN SKIN TUMORS AND THEIR CLINICOPATHOLOGICAL FEATURES Seborrheic keratosis is a benign tumor which occurs as a result of decrease or cessation in maturation of epidermal keratinocytes. The relationship between seborrheic keratosis and malign skin tumors is controversial. Though there are some articles reporting development of malignancy in milieu of seborrheic keratosis, other authors accept this relationship as coincidental. The aim of this study was to investigate the possible relationship and clinicopathological correlations between seborrheic keratosis and malignant skin tumors. 82 cases (46 male, 36 female) who apply to our in patient clinics between September 2000 and April 2001 with a diagnosis of seborrheic keratosis were included in this study. 100 biopsies from different lesions of 82 cases were obtained and evaluated histopathologically. Among 100 biopsies taken, in two biopsies (%2) get from two different patients, cellular atypical focuses were determined. The diagnosis of these two cases were common seborrheic keratosis. Histopathologically; one of them was acanthotic, the other one was hyperkeratotic type. Both of these lesions were light and dark brown with a heterogenous pigment distribution. One of the lesions was in a region under sun exposure, whereas other one was in a region with no sun light exposure. Because of the limited number of lesions investigated, we could not determine the statistical significance of our 2% result. In lesions of our cases, we found histopathologically atypical focuses despite the lack of malignancy indications such as clinical enlargement, bleeding and ulceration. Malignant transformation in seborrheic keratosis starts at microscopic levels. For this reason the clinical reflections of this state take much more longer time. Taking biopsies from lesions with a history of chronic irritation and long term sun light exposure is warranted. Keywords: Malign transformation, malignant tumours, seborrheic keratosis, VI -^ ><*