Phototherapy of mycosis fungoides

Mycosis fungoides (MF), the most common variant among cutaneous T cell lymphomas (CTCL), is characterized in its early stages by clonal proliferation of malignant T-cells in the skin manifesting as erythematous patches and plaques with a chronic course and progression to cutaneous tumors and extracutaneous organs in some patients. Skin directed therapies (SDT) are primarily used for effective palliation in early stage disease. Phototherapy with ultraviolet A radiation combined with 8-methoxypsoralen (PUVA) and with ultraviolet B radiation (UVB) has a longstanding history in the treatment of MF and are highly effective in inducing remissions. Patients with erythroderma and blood involvement benefit from treatment with extracorporeal photochemotherapy (ECP) where peripheral blood is exposed to PUVA. Phototherapy can be safely combined with systemic agents, most notably interferon-alpha and retinoids. Recently updated treatment guidelines have been published to provide evidence based algorithms for the stage-oriented treatment of MF. PUVA and narrow-band UVB (NB-UVB) are recommended as first line treatment for early stages with combination modalities reserved for refractory and more advanced cases and ECP is among the standard treatments for MF erythroderma. Areas of uncertainty relate to optimized treatment dose and schedules, the use of phototherapy for maintenance, and the role of newer phototherapeutic modalities (e.g. ultraviolet A1 radiation, excimer sources, photodynamic therapy) in the treatment of MF.