Pigmented Bowen’s disease presenting clinically as longitudinal melanonychia

Lucas S. Madureira, Department of Dermatology, Hospital de Base, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, São Paulo, Brazil Vivian W. Lederman, Department of Dermatology, Hospital de Base, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, São Paulo, Brazil Julia C. K. El Dib, Department of Dermatology, Hospital de Base, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, São Paulo, Brazil Paula F. M. Madureira, Department of Dermatology, Faculdade Ceres, São José do Rio Preto, São Paulo, Brazil Lucas K. Fernandes, Department of Dermatology, Hospital de Base, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, São Paulo, Brazil Eduardo C.N. Constantino, Department of Pathology, Hospital de Base, Faculdade de Medicina de São José do Rio Preto. São José do Rio Preto, São Paulo, Brazil

Bowen’s disease (BD) is a squamous cell carcinoma, which affects more the elderly population and is more prevalent in light-skinned individuals. It affects most frequently sun-exposed areas and generally manifests as a single erythematous, scaly, or crusted plaque, with irregular growth and generally precise limits. Its pigmented variant is less frequent and the nail localization is even more atypical. The gold-standard treatment is surgical excision with safety margins. This report presents a case of pigment BD, in a female patient, on the fifth toe of the right foot, manifesting as longitudinal melanonychia (ML). The lesion had been present for a few years but there was recent darkening. The objective of the work is to raise awareness of the importance of BD as a differential diagnosis of longitudinal ML and to highlight the importance of histopathological studies for diagnostic confirmation.

Keywords: Bowen’s disease. Squamous cell carcinoma. Epithelial and glandular. Neoplasms.