Promising therapeutic option for cutaneous plasmacytosis: 308‐nm excimer lamp

Abstract

Dear Editor, Cutaneous plasmacytosis (CP) is characterized by a reactive proliferation of mature plasma cells in the skin. 1 Several therapeutic modalities have been reported, with varying effects. We present a case of CP successfully treated with 308-nm excimer lamp.In December 2015, a 74-year-old Japanese man was referred to us because of an 18-month history of gradually Figure 1. (a) The patient, a 74-year-old man. On his trunk, 10-15-mm multiple infiltrating erythemas had presented. (b) The 311-nm narrowband ultraviolet B (NBUVB) therapy was performed once a week at an initial irradiation dose of 0.2 J/cm 2 . The dose was gradually increased at each visit, and reached 0.8 J/cm 2 20 weeks after the start of treatment. In March 2017, the 311-nm NBUVB therapy at a total 58 J/cm 2 showed only a slight effect on the cutaneous plasmacytosis (CP). (c) The 308-nm excimer lamp therapy was performed once a week at an initial irradiation dose of 100 mJ/cm 2 . The dose was gradually increased at each visit, and reached 220 mJ/cm 2 12 weeks after the start of treatment. In November 2017, the 308-nm excimer lamp therapy at a total of 9 J/ cm 2 showed a full effect on the CP. No obvious adverse events were observed. (d,e) Perivascular, periadnexal and lobular infiltrations of mature plasma cells were observed in the dermis to subcutaneous fat, histopathologically (hematoxylin-eosin, [d] scanning magnification, [e] 9400). (f,g) No light chain restriction was detected by in situ hybridization for Igj-and Igk-chain (j/k ratio, 0.6; [f] Igj 9200; [g] Igk 9200).

Cutaneous Plasmacytosis: Diagnostic and Therapeutic Challenge in a Patient with an Atypical Presentation

“…Systemic corticosteroids, thalidomide (probably associated with reduced IL6 secretion), ultraviolet-A (UVA) and narrow-band ultraviolet-B (NB-UVB) phototherapy (related to elevation of IL-10 with consequent IL6 suppression) are other options. 8,14 A good response was reported with 308-nm excimer lamp, with a mechanism supposedly similar to NB-UVB. 15 The present patient has not responded to topical or systemic corticosteroid therapy neither to NB-UVB and thalidomide.…”