Imatinib/thalidomide

Abstract

IgG kappa monoclonal gammopathy of undetermined significance, IgG multiple myeloma and morbilliform pruritic rash: case report A 58-year-old man developed IgG kappa monoclonal gammopathy of undetermined significance (MGUS), followed by multiple myeloma (MM), during treatment with imatinib for chronic myeloid leukaemia (CML). Additionally, he developed morbilliform pruritic rash on the trunk and bilateral upper extremities during treatment with thalidomide for IgG MM [routes and times to reactions onsets not stated; not all outcomes stated]. The man, who had been diagnosed with CML (December 2007) and treated with imatinib (until September 2015), had previously achieved complete molecular remission. At the age of 58 years (December 2015), he presented with recurrence of CML, and he started receiving imatinib 400mg daily. Within 2 weeks of re-initiation of imatinib, he exhibited an improvement in WBC count. However, he was found to have an elevated total protein level. Subsequently, electrophoresis was performed, and he was diagnosed with IgG kappa MGUS based on total M protein spike <3 g/dL. Bone marrow biopsy revealed <10% plasma cells. The man’s continued to receive imatinib for CML, while he was closely monitored for the progression of plasma cell dyscrasia. Molecular remission of CML was noted in November 2016. Between December 2015–April 2019, he experienced a steady increase in the paraprotein level. In May 2019, he developed further increase in creatinine and paraprotein level along with an increased serum free light chain ratio. In June 2019, a PET CT scan revealed increased uptake in the left fourth rib, right and left ischium and a lesion in the second lumbar (L2) vertebra. In July 2019, a bone marrow biopsy showed 50% plasma cells that expressed as CD 38, dim/partial CD 117, CD 138, CD 56 and kappa light chain restriction. Based on these findings, a confirmed diagnosis of IgG MM was made. It was noted that he developed IgG kappa MGUS and IgG MM secondary to imatinib. In September 2019 (at the age of ~62 years), for the treatment of ISS stage II standard risk myeloma, he started receiving thalidomide 50 mg/day daily for 21 days, followed by 7 days off (in cycles) along with bortezomib and dexamethasone. Also, imatinib was continued. After cycle 2 of the myeloma therapy, he developed a morbilliform pruritic rash over the bilateral upper extremities and trunk, and the rash was considered to be a side effect of thalidomide. Therefore, he was treated with unspecified steroids, and he continued to receive myeloma therapy including thalidomide. However, after cycle 5, he experienced recurrence of the morbilliform pruritic rash. Also, he developed conjunctival injection bilaterally, and he was diagnosed with meibomian gland dysfunction [aetiologies unknown]. Due to the rash and ocular symptoms, myeloma treatment was delayed. The symptoms improved with supportive care that included unspecified steroids, and later, complete resolution of the symptoms was noted. At the time of report, he has completed a total of six cycles of myeloma treatment in addition to imatinib therapy. He was referred to a transplant centre for his examination regarding bone marrow transplant. He did not experience any other side effects.