Epidemiology and outcomes research for MGUS, myeloma and amyloidosis.

The epidemiology of plasma cell dyscrasias clearly links to a complicated multi-factorial pathogenic pathway that at the individual patient level gives no clear indication of why the malignant process has occurred but factors in the environment and within the genome give clues and are discussed. MGUS is a pre-malignant disorder characterised by monoclonal plasma cell proliferation in the bone marrow and no end-organ damage; the patients are asymptomatic. Primary amyloidosis is a rare disorder that is characterised by deposition of amyloid fibrils composed of immunoglobulin light chain fragments; symptoms relate to the affected organ. Multiple myeloma is a malignant disease of plasma cells and with improvements in treatment, patients can now expect a doubling of median survival to 5 years, a 20% chance of surviving >10 years and a 50% chance of complete remission (CR), morphological and biochemical. The challenge is now to determine exactly what this means to the individual myeloma patient in terms of benefit, and to society as a whole and this is the basis of 'outcomes research' which is discussed in this review.