Background. Some skin lesions e.g. basal cell carcinomas are sometimes difficult to remove completely and frequent relapses can develop after their imperfect removal. In case the patient refuses to undergo a radical surgical intervention, more painful alternative like cryotherapy comes into consideration as a method of tumour destruction. Not even such a procedure does guarantee complete destruction of all tumour cells. During the last years new diagnostics and therapeutic methods like photodynamic diagnostic and photodynamic therapy have been developed and they became subjects of our interest. Methods and Results. Lesions were treated with photosenzitizer (meso-tetra-para-sulphonato-phenyl-porfine – TPPS4) administered in an injection or in the ointment under occlusion. Six to 24 hours later we checked presence of photosensitizer in the lesions and in positive cases we irradiated the lesions with light of suitable wave length (630 nm). Conclusions. PDD and PDT were used for diagnostics and treatment of different dermatoses (basal cell carcinomas, malignant melanoma metastases, verrucae vulgares, keratoacanthomas, solitary lesions of T lymphoma – mycosis fungoides, m. Bowen, psoriasis vulgaris, pustulosis palmoplantaris, solar keratoma) with very good medical and cosmetic effect. Results are presented in the table. Authors do not consider the PDT to be the only and miraculous method relevant to treatment of all skin tumours or other skin diseases. They are of the opinion that this technique, when properly used, can extend the scale of therapeutic methods. The advantage of PDT is its selectivity, good tolerance and generally good cosmetic effect.

        Key words: photodynamic therapy, TPPS4, epidermoma, basalioma, verrucae vulgares, malignant melanoma, solar keratomas, psoriasis vulgaris.