Iron Overload Pattern in Multiple Myeloma at Diagnosis Its Important Clinical Associations

Abstract

As a plasmaproliferative disorder, multiple myeloma (MM) is not expected to cause IO and actually there are no reports on this condition in MM. In this retrospective study, we evaluated serum iron test results in MM patients at diagnosis in order to find the frequency of IO. Iron overload pattern (IOP) was described as increased transferring saturation (> 45%) in the presence of normal to increased serum iron and ferritin levels. Among 90 newly diagnosed MM patients (54 male, 36 female, and the median age: 61 years, range: 31-86)IOP was found in 17 cases (17/90, 19%). There was a close association between lambda light chain type paraproteinemia and IOP (13/17 in IOP cohort vs 26/73 lambda paraproteinemia, p= 0.003). Half of the MM patients (7/14) with free lambda light chain paraproteinemia had IOP. The main reason of the elevated TS was increased serum iron level in IOP patients, 144 (+/- 71) vs 57 (+/- 24) pg/ml (p<.001). Four out of 17 IOP patients had extramedullary involvement and this was significantly more frequent than the other patients. Although high International Staging System risk disease (stage 2 or 3) was more frequent in IOP patients (15/15 vs 51/68, p= 0.03), we could not observe any difference regarding treatment response, and survival between these cases and others. In conclusion, IO is also not infrequent MM at diagnosis and it has some clinical associations.