Via practica 6/2007

THE NEW TRENDS IN THERAPY OF NONMELANOMA SKIN CANCERS

Nonmelanoma skin cancers (NMSCs) are the most common malignancies. The link between the sun exposure, skin type and NMSC is established. Basalioma, m. Bowen and actinic keratosis are commonly removed by cryotherapy, electrodesiccation, laser, topical cytostatic therapy, etc. Photodynamic therapy using skin photosensibilisation with delta aminolevulinic acid is new method for the treatment NMSCs. Photosensitizer is selectively accumulated in tumor cells. Selective interception of photosensitizer in malignic cells and following application of radiation at length 600 – 800 nm is leading to their destruction. Immunostimulative therapy with 5 % imiquimod cream is the second method. Periodic and long-lasting sun exposure leads to suppression of skin immunity. UV radiation has mutagenic effect on skin cells suppressing cell-mediated immunity response and originating in direct and indirect DNA damage. Previous reactions lead to cells proliferation developing into carcinoma. Topical imiquimod application direct and indirect indicates cytokines production, which stimulate immunity response resulting in tumor cells death with sequential tumor regression and damaged tissue regeneration.

Keywords: nonmelanoma skin cancer, therapy – photodynamic therapy, imiquimod.