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

Summary 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 Sézary 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.