[Treatment of so-called keloid with excision and postoperative electron irradiation]

Between 1988 and 1994, 110 patients with 139 so-called keloids site, which had been treated with conservative therapy were treated with excision, suture, and postoperative irradiation with a 4 MeV electron beam. They were irradiated within one or two days after surgery, for three consecutive days. The total doses were 15 Gy or 18 Gy per fractions for the most part. Control rates of true keloids and hypertrophic scars were 76.0% (57/75) and 93.8% (60/64), respectively, and the overall effectiveness rate was 84.2%. No remarkable side effects were observed. Transient hyperpigmentation was found in 44.6%. No carcinogenesis have been found in our series of patients. Considering the possibility of recurrence, side effects, and carcinogenesis, the indication of our treatment was decided. The result of our treatment using a low-megavolt electron beam was similar to that of published series using a low-energy X-ray. The advantages of the use of electron beam are that the peak of dose is the layer of the occurrence of keloid, and that the depth of penetration of radiation is limited without appreciable effect on the deeper structures. At present, the equipments of low-energy X-ray have been disposed. Our treatment using a electron beam will be an effective treatment.