Low-dose total skin electron beam therapy plus oral bexarotene maintenance therapy for cutaneous T-cell lymphoma

Background: Total skin electron beam therapy (TSEBT) combined with systemic therapy or maintenance treatment is a reasonable approach to enhance the remission rate and duration in mycosis fungoides (MF) and Sezary syndrome (SS). This study assesses the efficacy of oral bexarotene therapy after low-dose TSEBT for patients with MF and SS. Methods: In this prospective observational study, we recruited MF/SS patients for treatment with low-dose total skin electron beam therapy (TSEBT) with or without bexarotene therapy to describe outcomes and toxicities. Results: Forty-six subjects with MF or SS underwent TSEBT between 2016 and 2021 at our institute. Following TSEBT, 27 patients (59 %) received oral bexarotene treatment. The median follow-up was 13 months. The overall response rate (ORR) for the cohort was 85 %. The response rate was significantly higher with combined modality (CM) than TSEBT alone (96 % vs. 68 %, p = 0.03). Median progression-free survival (PFS) for the CM was 17 months versus five months following TSEBT alone (p = 0.001). One patient (4 %) in the retinoid group discontinued the bexarotene therapy because of adverse events. The administration of bexarotene therapy did not increase radiation- related toxicities. Conclusions: Response rate and progression-free survival might be improved with TSEBT in combination with oral bexarotene compared to TSEBT alone.