Polydactylous Bowen's disease of the nail.

We present three patients with Bowen's disease of the fingernail folds and beds in which there was polydactylous involvement and add those to five similarly afflicted patients described by other authors. Bowen's disease of the nail is a distinctive type of squamous cell carcinoma that differs from other variants. It is potentially an autochthonous process that can involve more than one nail with the passage of time. Seven-eighths of the patients described in this series were men. A majority had involvement of both hands. No metastases were seen.