A retrospective, descriptive study of patients with Mycosis fungoides treated by phototherapy (oral PUVA, NB-UVB) with a twice-weekly regimen at the Institute of Dermatology, Bangkok, Thailand, with an experiential timeline of 13 years.

Background: Phototherapy has been a first-line treatment for early-stage mycosis fungoides (MF) since 1976. Oral 8-methoxypsoralen plus ultraviolet A (oral PUVA) and narrow-band ultraviolet B (NB-UVB) are favorable modalities owing to their availability. In previous studies, phototherapy was conducted thrice per week initially, which is not feasible for many patients.

Objectives: To evaluate the initial clinical responses and time to relapse in patients with early-stage MF treated with oral PUVA and NB-UVB at a twice-weekly regimen.

Methods: We reviewed the records of patients with biopsy-proven MF who received oral PUVA or NB-UVB in 2002-2014. Demographic data, staging, response to initial course of phototherapy, and initial relapse-free interval were collected.

Results: Among 70 patients, 14 (20%) and 56 (80%) were treated with oral PUVA and NB-UVB, respectively. The majority had early-stage MF (IA, 22.9%, IB, 57.1%, and IIA, 4.3%). Oral PUVA led to a complete response (CR) in 2 (14.3%) patients and partial response (PR) in 7 (50%) patients; 17 (30.4%) and 25 (44.6%) patients, respectively, achieved CR and PR with NB-UVB. The number of treatments was similar in both groups. The cumulative dose was 520.7 J/cm for PUVA and 41.6 J/cm for NB-UVB. There was no initial relapse in the 2 (100%) patients and in 10 (58.8%) patients treated with oral PUVA and NB-UVB at 18 months and 9.14 months of follow-up, respectively.

Conclusion: Patients with early-stage MF can achieve clinical response with oral PUVA and NB-UVB, with a twice per week regimen. The initial relapse-free interval was longer than 1 year.