To the editor: The lesions of lymphomatoid papulosis (LyP) are classically distributed over the trunk and extremities in a generalized pattern, but in a few instances, confined to a segmental unilateral area. Here, we report a case of late-onset regional LyP successfully controlled by subcutaneous interferon alpha-2b and topical nitrogen mustard (NM) solution.
A 58-year-old woman was admitted to the hospital for a 5-year history of intensely pruritic lesions on the right thigh. She had been treated with various antihistamines, topical and systemic corticosteroids, but no obvious improvement was achieved. Dermatol cal examination showed crops of 0.5- to 1-cm, purple-red nodules and papules with central erosion and crust on the right thigh (Figure 1A). Pathological examination of a biopsy specimen showed a superficial and deep wedge-shaped, dense dermal infiltrate consisting of mononuclear lymphoid cells mixed with scattered or small clusters of large atypical cells and numerous inflammatory cells, such as histiocytes, small lymphocytes, and neutrophils (Figure 1B, 1C). Atypical mitoses were easily seen. Immunohistochemical analysis also revealed an infiltrate mainly consisting of T cells, which were positive for CD4 (Figure 1D), CD3 (Figure 1E), CD5, CD45RO, but negative for CD8, CD79a, CD20 (Figure 1F), and CD56. And the majority of the large atypical cells were CD30 positive (Figure 1G). A diagnosis of regional LyP, type A, was established. She was given subcutaneous injection of interferon alpha-2b at a dose of 3 million units three times per week and topical NM 0.2% solution once daily. Two months later, a complete resolution was achieved with hyperpigmentation and atrophic scar formation (Figure 1H). No hepatorenal damage or other side effects were observed at the end of the treatment, and no new lesions developed during 6-month follow-up.
Since LyP undergoes spontaneous resolution, nearly half of patients with LyP do not receive initial therapy. Indications for treatment are for cosmetic reasons or symptom relief. The treatment of LyP mainly includes psoralen plus ultraviolet A, low-dose methotrexate (MTX), oral antibiotics, systemic corticosteroids, interferon alpha, etc. Therapies shown to be effective include minocyclines,1 UVB phototherapy,2 and so on. Recently, oral bexarotene had been used to successfully treat a case of pruritic LyP.3 Our patient was treated with subcutaneous interferon alpha-2b and topical NM solution, which leaded to a complete remission of lesions with relief of symptoms two months later. Topical NM solution has been used since the late 1950s as a skin-directed therapy for the complete remission of cutaneous T-cell lymphomas (CTCLs), including LyP. NM is considered to be able to induce the apoptosis of T cells by producing free radicals, as well as by causing DNA alkylation and membrane lipid peroxidation. The therapeutic mechanisms of interferon-alpha are thought to involve a shift from a prevalent Th2 cytokine pattern to a Th1 pattern, restoration of skewed T-cell repertoire, and an increase in CD95 expression. In another report, topical corticosteroids plus local injections of interferon gamma failed to stop the progression of LyP localized to the right palm of a Japanese male.4 The difference in treatment outcomes may suggest that topical NM solution is more effective than corticosteroids in the control of regional LyP, and may be attempted when corticosteroids do not work as well as expected. Although no obvious side effects were observed in our patient, long-term safety of NM solution deserves continuous attention.
The prevalence rate of regional LyP is considered to be 2%-27% among all patients with LyP. Sharma et al5 reviewed 13 cases of regional LyP reported by English literature from 1994 to 2007, and concluded that regional LyP was more common in children and young adults with a mean age of 31 years (range 7-50 years) as compared to the more common widespread LyP that has its peak in the fifth decade of life. However, this is not always the case. Buder et al4 had reported a 56-year-old male patient with 1-year history of LyP recently. And, LyP developed until 53 years of age in our patient. The latter two cases may broaden our knowledge about the onset age of regional LyP.
1. Kim YJ, Rho YK, Yoo KH, Kim JY, Seo SJ, Hong CK, et al. Case of regional lymphomatoid papulosis confined to the periorbital areas. J Dermatol 2009; 36: 163-165.
2. Coelho JD, Afonso A, Feio AB. Regional lymphomatoid papulosis in a child-treatment with a UVB phototherapy handpiece. J Cosmet Laser Ther 2010; 12: 155-156.
3. Buder K, Wendel AM, Cerroni L, Goebeler M, Kerstan A. A case of lymphomatoid papulosis limited to becker's melanosis (J/OL). Dermatology 2013; 226: Epub ahead of print.
4. Kagaya M, Kondo S, Kamada A, Yamada Y, Matsusaka H, Jimbow K. Localized lymphomatoid papulosis. Dermatology 2002; 204: 72-74.
5. Sharma V, Xu G, Petronic-Rosic V, Gerami P. Clinicopathologic challenge. Regional lymphomatoid papulosis, type A. Int J Dermatol 2007; 46: 905-909.