Unusual presentation of seborrheic keratosis: A case report of giant pigmented lesion on the forehead

Abstract

INTRODUCTION AND IMPORTANCE: Seborrheic keratosis (SK) is a common benign epidermal tumor usually presenting as small, non-pigmented lesions on the skin. However, giant SK presenting as a pigmented variant is a rare occurrences, with limited documented cases in medical literature. CASE PRESENTATION: Here, we present a case report of a 70 year old female patient with an unusual giant warty cutaneous lesion prompting excisional biopsy. Histopathological examination revealed pigmented proliferative basaloid cell and pseudohorn cysts, characteristic of SK. Notably, the lesion exhibited pigmentation, adding to the rarity of the giant forms of SK case. CLINICAL DISCUSSION: Giant pigmented seborrheic keratosis (GPSK) is an uncommon form that shares clinical and dermatoscopic features, frequently causing misdiagnosis as malignant melanoma. CONCLUSION: Thus this report underscores the importance recognizing such atypical presentations of SK and highlights the need for histological evaluation to diagnose such variants.