A 60-year old male with a past medical history of hypertension presented with a 2-month history of new onset upper back pain. Initial work up showed quantitative IgA level of 7,850 mg/dL. After a complete work up, he was diagnosed with Durie-Salmon stage IIA, IgA multiple myeloma and was started on lenalidomide plus dexamethasone as part of a double blind, randomized clinical trial evaluating lenalidomide plus dexamethasone compared to placebo plus dexamethasone for newly diagnosed multiple myeloma. After 3 cycles of dexamethasone (40 mg/day on Days 1–4, 9–12 and 17–20) plus lenalidomide (25 mg/day for 28 days), he was moved onto maintenance therapy with dexamethasone (40 mg/day on Days 1–4 and 15–18) plus lenalidomide (25 mg/day for 21 days).
The patient was compliant with both lenalidomide and dexamethasone. Dexamethasone, originally given at 40 mg for four days every two weeks, was changed to 20 mg for four days every two weeks after approximately one year of starting therapy. This dose was further decreased to 20 mg/week after the unblinding of the protocol at 18 months of therapy. Dexamethasone was later discontinued after 50 months and 24 days of therapy due to mood changes and insomnia. During this entire therapy period, adverse events included grade 1 diarrhea and neuropathy; these were treated symptomatically.
The patient was closely monitored throughout this therapy and his multiple myeloma stayed biochemically stable until he had received a total 68 cycles of lenalidomide (68 months). At 68 months of therapy, he demonstrated signs of progression; quantitative IgA increased to 529 mg/dL, SPEP/immunofixation showed IgA kappa of 0.42 g/dL (), kappa to lambda ratio was 3.06, and bone marrow biopsy showed 67.8% plasma cells. Lenalidomide was discontinued and he was evaluated for HDM with ASCT.
Trend of Immunoglobulin A (IgA) monoclonal protein during treatment.
He underwent mobilization of stem cells using filgrastim 16 mcg/kg/day for four days and plerixafor 0.24 mg/kg administered on Day 4 (no peripheral CD34 count checked on Day 4). The peripheral CD 34 cell count was 44.94/µL on Day 5. Total CD 34 cells collected were 6.37 million per kg of actual body weight. The stem cells were collected in one day. The total volume of blood processed was 28,674 milliliters. Subsequently, he underwent stem cell transplant with melphalan 140 mg/m2 because of his low GFR (55 mL/min/1.73 m2). His neutrophils and platelets successfully engrafted post ASCT.