The indications for total cutaneous electron beam radiation therapy of mycosis fungoides.

From 1977 to 1984, we treated 34 patients with mycosis fungoides and 9 patients with B cutaneous lymphomas. Eighteen patients with mycosis fungoides were treated with total skin electron irradiation (TSEI) and had a minimum follow-up of 15 months (range 15 months to 7 years). The lowest electron energy of the linear accelerator was 8 MeV therefore we placed a plexiglas screen between the patient and the machine; the resulting electron energy was 4 MeV. The total dose was 30 Gy delivered in 12 fractions over 40 days. There were 8 males and 10 females. The median age was 48 years (ranging from 13 to 78 years). All patients were staged as follows: Stage A = superficial lesions covering less than 50% of the body surface; Stage B = superficial lesions covering more than 50% of the body surface; Stage C = tumors involving the skin, lymph nodes and/or visceral organs. Five patients with Stage A (5/5) and 5 patients with Stage B (5/5) had a complete remission, 1 stage A patient relapsed 6 months after completion of treatment. All the Stage B patients recurred between 3 and 15 months. The recurrences were localized to the skin and were well controlled with topical nitrogen mustard or puvatherapy. Among the Stage C patients, 3 did not respond to treatment and died of their disease; the remaining 5 patients achieved complete remission but they all relapsed from 2 to 9 months following completion of treatment. The median follow-up was 32 months and the average time for relapse was 6.5 months. All relapses except one (15 months) occurred within the first year. We feel that total skin electron irradiation is indicated in Stage A and B patients. However, we feel Stage C patients should receive TSEI for palliative purposes only.