Incidental Detection of Bowen's Disease in a Patient Presenting With Dermatophytosis: A Case Report of Two Distinct Back Lesions.

Bowen's disease (squamous cell carcinoma in situ) is an intraepidermal malignancy that can clinically resemble benign inflammatory or infectious dermatoses. The coexistence of dermatophytosis and Bowen's disease can make diagnosis challenging. A 60-year-old man presented with itchy, scaly lesions on the upper back, clinically consistent with tinea corporis. Examination also revealed a separate dark plaque with well-defined borders, distinct from the dermatophytic lesions. Dermoscopy showed eccentric glomerular vessels with brown pigmentation, raising suspicion for Bowen's disease. The fungal infection was treated with standard antifungal therapy, and the Bowen's lesion was managed with topical 5-fluorouracil (5-FU). This case highlights the importance of thorough skin examination, and dermoscopic assessment proved particularly useful. Bowen's disease may occur without noticeable symptoms, and dermoscopy can help distinguish benign from malignant lesions by revealing characteristic features, making it a valuable tool for improved patient management.