Photochemotherapy (psoralen/UVA (PUVA)) is an efficient therapeutic tool for a wide range of skin diseases. Concern, however, exists regarding the long-term carcinogenic effects of this treatment modality and, as a consequence, is being used less frequently. PUVA remains an important treatment in our therapeutic armamentarium but must be used with caution in those patients with risk factors and cumulative dose exposure must be limited. PUVA-induced cancers show features in common with skin cancers induced by immunosuppressed organ transplant recipients. Tumours in the latter group of individuals are, however, much more aggressive and difficult to manage.