Small cell lung carcinoma and Bowen's disease 40 years after arsenic ingestion

A non-smoking woman presented with ectopic ACTH syndrome associated with disseminated small cell carcinoma of lung. The patient had Bowen's disease and had taken oral arsenic for psoriasis 40 years ago. It is postulated that the previous therapeutic arsenic ingestion caused both her arsenical dermatosis and her small cell carcinoma of lung.