Mogamulizumab and Concomitant Hypofractionated Low-Dose Total Skin Electron Beam Therapy (2 × 4 Gy) in Cutaneous T-Cell Lymphoma: Proof of Principle, Report of Two Cases.

Patients with advanced-stage mycosis fungoides (MF IIB-IVB) and Sézary syndrome (SS) have poor prognoses, with survival ranging from 4.7 to 1.4 years depending on the disease stage. There is a need for therapeutic approaches that lead to long-lasting responses and improved quality of life and survival. Mogamulizumab, a humanized antibody against the CCR4 molecule, and low-dose total skin electron beam therapy (TSEBT) are two known established treatments for MF and SS as a monotherapy. However, little is known about the potential additive effect on the combination of both treatments. We report here for the first time the concurrent use of low-dose hypofractionated TSEBT (2 × 4 Gy) with mogamulizumab. Based on two relapsed/refractory and advanced-stage CTCL patients, we show that this combination may be well tolerated in advanced-stage MF or SS and may potentially lead to an additive treatment effect on response times, particularly in the skin and blood within two weeks. We propose that this combination may be a treatment option for patients with SS. Further research is needed to understand the efficacy and tolerability profile of this therapeutic combination and to determine if there is an additive effect of the combination on the response rates when compared with the monotherapy.