ABSTRACT
Bowen's disease is a premalignant condition, which may evolve into invasive carcinoma. Most invasive carcinomas arising from Bowen's disease show squamous differentiation, but rarely basaloid, pilar, pilosebaceous or sebaceous differentiation. We herein describe two cases of invasive carcinoma arising from Bowen's disease. First case, a 78-year-old male, presented with an erythematous plaque with ulcerated and fungating changes on his back. Biopsy specimen revealed Bowen's disease transformed into invasive squamous cell carcinoma. Second one, a 67-year-old male who had been diagnosed histologically as Bowen's disease on the right inguinal area 5 months ago, complained of enlargement and infiltration of the previous lesion. Biopsy specimen showed invasive carcinomatous change of basosquamous differentiation. Our cases represent unusual invasive changes of Bowen's disease into squamous cell carcinoma and carcinoma of basosquamous differentiation.