Annular pigmented actinic keratosis mimicking lentigo maligna melanoma in a 75-year-old female: An unusual presentation

Abstract

Pigmented actinic keratosis (PAK) is an uncommon variant of actinic keratosis that can mimic different pigmented lesions, which may be benign or malignant. The diagnosis of PAK is often challenging because of overlapping features with lentigo maligna melanoma (LMM). Clinically, lesions of both conditions almost look similar; the diagnoses must be established histologically and with the help of immunostaining whenever needed. The distinction between a large PAK and LMM is important because their prognosis and management differ. We present a 75-year-old female with annular brown-to-black-colored maculo-plaque on forehead having clinical suspicious of melanocytic malignancy; which was diagnosed with a PAK on biopsy with help of histopathology and confirmed with Melan A/MART-1 immunostaining.

Keywords

• lentigo maligna melanoma
• melan a/mart-1
• pigmented actinic keratosis