PHOTODYNAMIC THERAPY OF CUTANEOUS METASTASES OF BREAST-CANCER AFTER LOCAL APPLICATION OF MESO-TETRA-(PARA-SULFOPHENYL)-PORPHIN (TPPS4)

Nine patients with cutaneous metastases of breast cancer were treated using photodynamic therapy. Meso-tetra-(para-sulphophenyl) porphin (TP PS4) was applied locally at a dose of 0.15-0.3 mg directly to the lesi on. The light source was an argon dye laser emitting light of 630 nm a t a fluence rate of 312-680 mW cm(-2) and a fluence of 150 J cm(-2). N o signs of local or systemic side effects or toxicity of the photosens itizer were observed. Treatments were well tolerated with no photosens itivity of the skin. Complete destruction of the tumour was observed i n three patients, reduction of the tumour size by more than 50% in two patients, reduction of the tumour size by less than 50% in two patien ts and no regression in two patients. The advantages of this method in clude the high concentration of the photosensitizer in the tumour, the extremely low total dose and the lack of side effects. The disadvanta ges include the less homogeneous distribution of the photosensitizer i n the tumour tissue compared with that obtained by intravenous applica tion.