Phototherapy modalities are frequently used in the treatment of patch and plaque mycosis fungoides (MF), but consensus recommendations on treatment regimens are variable.

We sought to investigate current practice variation in patch and plaque MF phototherapy treatment and review the relevant literature.

We conducted a cross-sectional online survey of International Society of Cutaneous Lymphomas members and literature review.

Survey response rate was 29%. Psoralen plus ultraviolet (UV) A (PUVA) and narrowband UVB were the most common phototherapy modalities used for patch and plaque MF treatment, with a predilection for PUVA in cases of more extensive disease and increasing skin phototype. For phototherapy treatment regimens, survey and literature results support: (1) narrowband UVB 3 times per week in the initial clearing regimen continued until clearance; and (2) PUVA 2 to 3 times per week in the initial clearing regimen, continued until clearance. Maintenance therapy regimens for narrowband UVB and PUVA varied widely from no additional treatment to one treatment per week for 5 years or more. There is not evidence to show whether phototherapy can prevent relapse or prolong disease-free interval.

Small survey size of specialty interest group and limited response rate are limitations.

Although phototherapy initial clearing regimens for MF are generally consistent, variability and lack of consensus remain in the duration and frequency of maintenance therapy.