Promising Efficacy with the 308 Nm Excimer Laser Phototherapy in Early Stage Mycosis Fungoides

Mycosis fungoides is the most common type of cutaneous T-cell lymphoma. Early stage disease is effectively managed with skin directed therapies such as UV light and topical steroids. Excimer laser (EL) delivers monochromatic, UVB light at a wavelength of 308 nm via hand held device that covers an area of 2 × 2 cm. It generates a short-pulse radiation that is concentrated on an affected area of skin, thereby allowing a delivery of higher dose on precisely targeted tissue. In contrast to other phototherapy techniques such as narrow band UV light, the EL is ideally suited for patients with small number of patch lesions. Although EL was successfully utilized in the management of psoriasis and vitiligo, there is not extensive experience with this modality in patients with CTCL.

To assess safety and efficacy of EL therapy in patients with early stage MF who failed ≥1 skin directed therapy.

This is a retrospective analysis of seven consecutive patients with stage 1 MF treated with EL phototherapy between January 2011 and August 2011 in a single institution. Seven patients with histologically confirmed common type MF, and one patient with folliculotropic MF received 308 nm EL therapy after failure of at least one prior skin directed therapy. The median age was 48 years (range 24–77 yrs). Four (57%) were male, 3 (43%) were female, six (86%) were Caucasian, and 1(14%) were African American. Biopsies and photos were obtained at diagnosis and after the completion of 24 treatments.

Treatment was initiated at a dose of 200 millijoules (mJ) and was increased by 10–15% each subsequent treatment. The max dose of treatment ranged from 240 mJ to 850 mJ. The total number of administered treatments was 24 delivered over period of 3 months. The median number of treated lesions was 2 (range 1–5). The surface area of treated lesions was <10%. Six patients achieved clinical improvement in appearance of lesions and intensity of pruritis; 2 (29%) achieved clinical remission as confirmed with photos and post-treatment biopsies. One (14%) patient developed first degree burn and 1 (14%) patient developed pruritis. These resolved by the second treatment with EL. There were no treatment-related serious adverse events observed.

Our results suggest that EL is effective and well tolerated skin-directed treatment modality for selected patients with early stage MF. However, longer follow-up will be required to assess durability of responses. Advantages of this approach include shorter treatment duration and lower risk of carcinogenesis in the non-affected areas of skin. Prospective study with a larger cohort of patients is necessary to further assess efficacy and safety of this approach.

No relevant conflicts of interest to declare.