Photodynamic therapy of cutaneous metastases of breast cancer after local application of meso-tetra-(para-sulphophenyl)-porphin (TPPS4).

Nine patients with cutaneous metastases of breast cancer were treated using photodynamic therapy. Meso-tetra-(para-sulphophenyl)-porphin (TPPS4) was applied locally at a dose of 0.15-0.3 mg directly to the lesion. The light source was an argon dye laser emitting light of 630 nm at a fluence rate of 312-680 mW cm-2 and a fluence of 150 J cm-2. No signs of local or systemic side effects or toxicity of the photosensitizer were observed. Treatments were well tolerated with no photosensitivity of the skin. Complete destruction of the tumour was observed in 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 patients and no regression in two patients. The advantages of this method include the high concentration of the photosensitizer in the tumour, the extremely low total dose and the lack of side effects. The disadvantages include the less homogeneous distribution of the photosensitizer in the tumour tissue compared with that obtained by intravenous application.