Low- vs. Middle-dose Total Skin Electron Beam Therapy for Mycosis Fungoides: An Efficiency-based Retrospective Survey of Skin Response
Annelies Taverniers, Aurélie Du-Thanh, Marie Charissoux, Christine Kerr, Olivier Dereure
Optimal doses of total skin electron beam therapy for mycosis fungoides remain to be established. Clinical efficiency and adverse effects of middle-dose (25 Gy) vs. low-dose (10–12 Gy) total skin electron beam therapy were retrospectively compared in a series of 14 and 12 mycosis fungoides, respectively. Overall skin response rate was 96.2% (92.9% middle-dose and 100% low-dose; not significant (NS)). Overall complete and partial skin response rates were 57.7% (42.9% middle-dose and 75% low-dose; NS) and 38.5% (50% middle-dose and 25% low-dose; NS), respectively. All responding patients relapsed after an overall median time of 5 months (7 months middle-dose vs. 4 months low-dose; p = 0.164, NS). Tolerance was equally fair in both groups, with only grade 1 and 2 adverse events observed in 100% vs. 66.7% of patients in middle-dose and low-dose groups (NS). Although no significant difference was observed, middle-dose protocol may be recommended owing to a longer relapse-free survival for a similar tolerance.
Mycosis fungoides, the most frequent primary cutaneous lymphoma, can be treated with total skin electron beam therapy, usually advocated as a second- or third-line treatment. However, the optimum dose protocol remains to be established. This study indirectly compared 2 dosages (low- and middle-dose) in a retrospective series. A response was obtained in almost all patients regardless of the dosage, but all responding patients relapsed after a relatively short delay. Tolerance was fair for both protocols. As relapse-free survival was almost twice as long in the middle-dose protocol compared with the low-dose, this might be the best choice for management of mycosis fungoides. However, because middle-dose total skin electron beam therapy, unlike low-dose, can be repeated only once during a patient’s disease course, maintenance treatment should be investigated in this setting.