Delayed Hypersensitivity Reaction to Lenalidomide: 2 Different Clinical Patterns in the Same Patient.

Abstract

Lenalidomide is an immunomodulatory and antiangiogenic agent approved for the treatment of oncological and inflammatory diseases, such as multiple myeloma, myelodysplastic syndrome (MDS), and mantle cell lymphoma. It is administered alone or with dexamethasone in relapsed and refractory multiple myeloma or as maintenance therapy following autologous stem cell transplantation [1]. Lenalidomide has been associated with cutaneous eruptions [2]. Lowering the dose to prevent cutaneous reactions is ineffective [3,4]. Skin reactions have been described in approximately 21% of patients and are the most frequent adverse event with this drug [5]. Truly allergic reactions are difficult to distinguish from toxic adverse effects in patients receiving lenalidomide. Immediate and delayed hypersensitivity reactions are rare, with only a few cases reported, most of which did not involve a complete allergological work-up [6]. Hypersensitivity reactions include urticaria, exanthema, drug reaction with eosinophilia and systemic symptoms syndrome, Stevens– Johnson syndrome, and toxic epidermal necrolysis [2,3,7]. We report a case involving both skin toxicity and a true delayed hypersensitivity reaction to lenalidomide. The patient was a 78-year-old man with a history of prostate cancer in 2012 in complete remission and current del (5q) MDS type RAEB 1. He started treatment with 10 mg of lenalidomide for 21 days every 28 days. Following the second cycle, 3 days after the dose, he developed erythematous maculopapular exanthema on the thorax, back, and limbs, with no mucosal or systemic involvement. Oral corticosteroids were administered, and the reaction resolved within 15 days. Lenalidomide was discontinued, and he was referred to our allergy department. After signing an informed consent document, the patient underwent patch tests with lenalidomide at 10% in dimethyl sulfoxide (DMSO), and readings at day 2 and day 4 were negative. We performed patch tests with lenalidomide in DMSO because it is a useful vehicle that Manuscript received October 31, 2018; accepted for publication January 30, 2019.