[Dermatologic radiotherapy--today, yesterday, tomorrow].

Dermatologic therapy with ionising radiation has changed in the last 30 years. Adapted to the limitations of the area of indication, the improved radiotechnique, as well as the stricter working conditions, it is still today an important therapeutic method. As there are to be expected increased numbers of malignant diseases of the skin, radiotherapy will be an essential part of dermatologic tumor therapy in the near future.