Electron beam therapy is not inferior to superficial x-ray therapy in the treatment of skin carcinoma

Purpose : To compare recurrence rates and cosmetic results after electron beam therapy vs. superficial x-ray therapy for nonmelanoma skin carcinoma. Methods and Materials : A retrospective analysis was performed on 389 histologically confirmed basal cell and squamous cell cell carcinomas of teh skin, treated with either superficial x-rays or electron beam therapy, with regard to local control rates and cosmetics, as scored with an arbitrary three-point scale. Results : The overall local recurrence rate was 4.9 (19 out of 389). For small tumors (irradiated surfaces ≤ 10 cm 2) a local recurrence rate of 2.2% was observed, both after electron beam therapy and after superficial x-ray therapy. Tumor size and previous treatment proved to be important prognostic factors with regard to control rate. The well-fractionated electron beam therapy yielded better cosmetic results than the large fraction surperficial x-ray therapy. Conclusion : Electron beam treatment is not inferior to superficial x-ray treatment and even better for larger tumors. The inferior results of electron beam therapy reported in literature might be due to technical factors, which are discussed.