Phototherapy of human tumours using haematoporphyrin derivative.

Photoradiation therapy (phototherapy) is a recently introduced treatment for malignant tumours, which depends on the activation of a photoreactive drug selectively localized to tumours. An experience in 27 patients with haematoporphyrin derivative is described. The haematoporphyrin derivative was activated by light of 630-nm wavelength, which was delivered to cutaneous tumours from a specially designed incandescent lamp and to deep tumours through a quartz fibre from a laser system. Tumours were eradicated in five patients and incomplete tumour destruction was observed in 14 others. The only significant side effect was temporary cutaneous photosensitivity. This form of treatment has considerable potential, particularly when other treatments have either failed or cannot be applied. However, it is premature to formulate indications for its use. Rapid technological developments can be anticipated which will greatly enhance the efficacy of photodynamic destruction of tumours.