ALCL, pc-ALCL is more likely to present on the head and neck and has a better prognosis.2 LyP is not classified as a lymphoma,but rather exists on a spectrum of lymphoproliferative disorders with pc-ALCL.3 Histologically, they are difficult to differentiate,but clinically pc-ALCL is suggested by size >2 cm and lack of the typical waxing and waning presentation of LyP. Comparedto CD30+ MF with large cell transformation, pc-ALCL typically affects younger patients who lack a history of MF. Histology shows less epidermotropism and a greater number of abnormal T-cells. Clinically, pc-ALCL presents as fewer, more localized lesions that have a higher rate of spontaneous regression than in CD30+ MF.Many traditional treatments are expensive, invasive, and associated with significant adverse events. For pc- ALCL involving few lesions, therapies include surgery and radiotherapy.3 Multifocal lesions are treated with radiotherapy or low-dose methotrexate. Other treatment options include topical steroids, oral bexarotene, and brentuximab vedotin (BV). BV is a monomethyl auristatin E-conjugated monoclonal antibody directed against CD30 that was shown to induce complete remission from pc-ALCL in a mean of 5.2 weeks.5 Peripheral neuropathy (57.2%) and fatigue (35.6%) are the most frequently reported adverse events. In addition, BV is administered as an infusion, and has significant financial cost. Imiquimod is a topical toll-like receptor agonist approved by the FDA for genital warts, actinic keratosis, and primary superficial basal cell carcinoma.6 It is used off-label to treat other dermatologic conditions, including cutaneous flat warts and acyclovir-resistant herpes simplex virus infection. It is inexpensive and has a favorablesafety profile with side effects including skin irritation or rash, flu-like symptoms, headache, and infection.6 Topical imiquimodhas been previously reported as effective against MF.7 Topical imiquimod therapy has achieved complete resolution of pc-ALCL in six other cases, summarized in Table 1.1,8-10 For patient 4, imiquimod therapy was initiated for a presumed keratoacanthoma; biopsy results later diagnosed pc-ALCL.8 Patients 5-7 received more invasive forms of therapy without resolution before initiating imiquimod.9,10 All patients achieved resolution with topical imiquimod within eight weeks and reported no adverse events. Further investigation is needed to evaluate the efficacy and safety profile of imiquimod in patients with pc-ALCL.While pc-ALCL typically has a favorable prognosis, traditional treatment may be expensive, invasive, and associated with significant adverse events. These findings highlight topical imiquimod as a possible alternative for first line therapy to treat pc-ALCL.
None of the authors have any conflicts of interest to disclose.
1. Didona B, Benucci R, Amerio P, et al. Primary cutaneous CD30+ T-cell lymphoma responsive to topical imiquimod (Aldara). Br J Dermatol. 2004;150:1198-1201.2. Lee WJ, Moon IJ, Lee SH, et al. Cutaneous anaplastic large-cell lymphoma (ALCL): a comparative clinical feature and survival outcome analysis of 52 cases according to primary tumor site. J Am Acad Dermatol. 2016;74:1135- 1143.3. Willemze R, Jaffe ES, Burg G, et al. WHO-EORTC classification for cutaneous lymphomas. Blood. 2005;105:3768-3785.4. Fauconneau A, Pham-Ledard A, Cappellen D, et al. Assessment of diagnostic criteria between primary cutaneous anaplastic large-cell lymphoma and CD30-rich transformed mycosis fungoides; a study of 66 cases. Br J Dermatol. 2015;172:1547-1554.5. Enos TH, Feigenbaum LS, Wickless HW. Brentuximab vedotin in CD30 primary cutaneous T-cell lymphomas: a review and analysis of existing data. Int J Dermatol. 2017;56:1400-1405.6. Aldara™ (imiquimod) Cream [package insert]. Loughborough, England: 3M Health Care Limited; 2007.7. Lewis DJ, Byekova YA, Emge DA, Duvic M. Complete resolution of mycosis fungoides tumors with imiquimod 5% cream: a case series. J Dermatolog Treat. 2017;28:567-569.8. Calista D, Riccioni L, Bagli L, Valenzano F. Long-term remission of primary cutaneous neutrophil-rich CD30+ anaplastic large cell lymphoma treated with topical imiquimod. a case report. J Eur Acad Dermatol Venereol. 2016;30:899-901.9. Ehst BD, Dreno B, Vonderheid EC. Primary cutaneous CD30+ anaplastic large cell lymphoma responds to topical imiquimod cream. Eur J Dermatol. 2008; 18:467-468.10. Coors EA, Schuler G, Von den Driesch P. Topical imiquimod as treatment for different kinds of cutaneous lymphoma. Eur J Dermatol. 2006;16:391-393.