Fine-Tuning Low-Dose Total Skin Electron Therapy for Optimal Management of Cutaneous T-Cell Lymphoma: A Comparative Analysis of Regimens

Abstract

BackgroundLow-dose total skin electron beam therapy (TSEBT) is a proven treatment for managing cutaneous T-cell lymphoma (CTCL) and Sezary syndrome with skin burden. We performed a retrospective comparison of response rates and time to progression for patients receiving low-dose TSEBT based on dose per fractionation, total dose, and stage. MethodsOne hundred and ten patients with CTCL and Sezary syndrome were treated with 135 courses of low-dose (400-1500 cGy) TSEBT or STSEBT (subtotal skin electron therapy) at multiple centers of a single institution between 8/2003 and 6/2023. Patients were stratified according to total dose, dose per fraction, and stage. ResultsThe median follow-up was 301 days [IQR 141, 767]. The median age at treatment was 69.9 years (range 29.7 – 96.5). T-stage distribution was as follows: 3 (2.7%) T1, 74 (67.3%) T2, 16 (14.5%) T3, and 17 (15.5%) T4. AJCC 8th edition Stage distribution was as follows: 3 (2.7%) IA, 53 (48.2%) IB, 3 (2.7%) IIA, 16 (14.5%) IIB, 8 (7.3%) IIIA, 19 (17.3%) IVA, 8 (7.3%) IVB. There was no significant difference in disease distribution between patients treated with different fractionation schemes. The overall response rate was 89.6%. Forty-four courses (32.6%), 34 courses (25.2%), and 43 (31.9%) resulted in a complete, near-complete, and partial response, respectively. Fourteen courses (10.4%) resulted in no clinical response. For all patients, the median time to response was 43.0 days (IQR 23.0 – 70). The median time to skin progression for all patients was 107.5 days [IQR 67.8 – 233.5]. ConclusionsThis analysis demonstrated that CTCL patients treated with low-dose RT delivered over various fractionation schemes had similar overall response rates and median time to progression.