Multiple Myeloma as a Secondary Malignancy in a 44-year old Male Nigerian with Chronic Myeloid Leukaemia: A Case Report

Abstract

The occurrence of multiple myeloma (MM) and chronic myeloid leukaemia (CML) in the same patient is very rare. Cytopenias may develop in patients with CML during the course of treatment with tyrosine kinase inhibitors (TKIs) as a result of drug-related bone marrow suppression or disease progression. This report describes a rare case of MM which presented with persistent anaemia and neutropenia after 35 months of diagnosis of CML in a 44-year old male Nigerian who was treated with Imatinib mesylate. During the course of investigation of the cause of the cytopenias, bone marrow aspiration revealed plasmacytosis of 40%. Serum protein electrophoresis and immunofixation revealed elevated monoclonal IgG 19.2g/L (reference: 7.0 – 16.0g/L) and kappa (k) light chain 32.9mg/L (reference: 3.3 – 19.4mg/L). Serum freelight chain ratio was 4.3 (reference: 0.26 – 1.65). Urinary Bence-Jones protein (BJP) was detected, identified on immunofixation as k light chain protein. Serum beta-2-microglobulin was 2.4mg/L (reference: 1.0 - 2.0mg/L). The patient was treated with chemotherapy and autologous stem cell transplant (Auto-SCT) at the Hammersmith Hospital, London, United Kingdom. To our knowledge, this is the first report of the development of secondary MM in a Nigerian CML patient on Imatinib therapy and also the first report of the treatment of such with AutoSCT.