Dermatological dichotomy: Atopic dermatitis or mycosis fungoides?

The presence of atopic dermatitis (AD) and mycosis fungoides (MF) presents diagnostic challenges due to their shared clinical features. AD, a chronic skin disorder characterized by pruritic and inflamed lesions, shares these features with MF, which is the most common cutaneous T-cell lymphoma. A 19-year-old male, who had a history of childhood AD, developed eczema-like lesions on his forearms, neck, and head. Initially, allergic contact dermatitis was suspected due to his occupational metal exposure. However, despite treatment with topical therapies, his condition worsened, requiring 3 cycles of oral corticotherapy. Notably, his lesions appeared atypically, affecting areas such as the scalp and nonflexural regions. Histopathological examination played a crucial role in the diagnostic process. While the initial biopsy suggested parapsoriasis, a second scalp biopsy confirmed MF. Despite their clinical similarities, AD and MF require distinct diagnostic approaches. This case emphasizes the need to consider MF as a diagnostic possibility, even in individuals with a history of AD. Early MF diagnosis enables tailored treatment, including topical therapies and narrowband ultraviolet B phototherapy. A multidisciplinary approach, advanced techniques such as immunophenotyping, and early identification are essential for providing optimal patient care. The shared clinical features of AD and MF suggest potential common mechanisms, underscoring the need for further research to enhance treatment strategies and patient care.