Clinical characteristics of a group of patients with multiple myeloma who had two different λ light chains by immunofixation electrophoresis: A retrospective study from a single center

The presence of two light chain bands on immunofixation is associated with poor outcomes in newly diagnosed multiple myeloma patients

We aimed to describe the clinical and biological characteristics and the prognosis of patients presenting with an additional light chain (LC) band along with a complete monoclonal protein on immunofixation (IF).An 8-year descriptive study was conducted to assess all cases with confirmed monoclonal gammopathies (MG). We studied those with an entire M-protein with 2 bands of LC of the same isotype based on the results of IF. Data were collected from patients' files.Among 548 cases of MG, we found 32 cases (5.8%) with an additional LC band. We included 28 patients (5%) with a confirmed diagnosis of multiple myeloma (MM). The m/f ratio was 2.5 with a median age of 63 years [32-80 years]. All MM patients had anemia, 16 (57%) had renal failure, 14 (50%) had lytic lesions, 9 (32%) received hemodialysis, and 7 (25%) had hypercalcemia. The free-kappa-lambda ratio was abnormal in all cases: median = 0.07 [0.002-58.57]. The mean overall survival (OS) was 22 months ± 38.76.Fifteen MM patients (48%) received chemotherapy, and 7 (22%) autologous stem cell transplants (SCT). Patients who received SCT had an OS higher than those who received other treatments (p = 0.038). OS was low in patients with high β2microglobulin levels (rho = -0.791; p = 0.001), and abnormally low free-kappa-lambda ratio (rho = -0.852;p = 0.04).The presence of an additional LC band with a complete monoclonal protein seems to identify newly diagnosed MM patients with poor outcomes and frequent renal impairment.

Evaluation of the AGE/sRAGE Axis in Patients with Multiple Myeloma

Glycative stress influences tumor progression. The aim of the present study was to evaluate the advanced glycation end products/soluble receptor of advanced glycation end products (AGE/sRAGE) axis in patients with multiple myeloma (MM). Blood samples were taken from 19 patients affected by MM and from 16 sex-matched and age-matched healthy subjects. AGE and sRAGE axis were dosed in patients with MM and matched with controls. AGEs were measured by spectrofluorimetric methods. Blood samples for the determination of sRAGE were analyzed by ELISA. AGE levels were significantly reduced in patients with respect to controls. Instead, sRAGE was significantly elevated in patients affected by MM compared to healthy subjects. Moreover, we showed that there was a statistically significant difference in sRAGE according to the heavy and light chain. IgA lambda had significantly higher sRAGE values than IgA kappa, IgG kappa, and IgG Lambda MM patients. From our data emerges the role of the sRAGE/AGE axis in MM. Since AGE is a positive regulator of the activity of RAGE, circulating sRAGE concentrations may reflect RAGE expression and may be raised in parallel with serum AGE concentrations as a counter-system against AGE-caused tissue damage. Serum concentrations of AGE and sRAGE could therefore become potential therapeutic targets.

Excess Free Light Chains in Serum Immunofixation Electrophoresis: Attributes of a Distinctive Pattern

Serum and urine protein electrophoresis and immunofixation are essential for identification and categorization of M protein/monoclonal protein. Based on the number of discrete bands identified the condition can be a monoclonal, biclonal or triclonal gammopathy. A subset of cases show an interesting pattern on immunofixation electrophoresis, with a complete immunoglobulin molecule, along with excess free light chains where in one light chain band shows similar mobility as the heavy chain, while the other light chain band of same isotype has a different mobility. Over a 3 year study period, 420 immunofixation electrophoresis gels were studied to select the cases with the typical pattern as described. The clinical records where searched for data of baseline evaluations done prior to starting therapy, including clinical presentation, biochemical parameters, hemogram and bone marrow examination. Twenty cases (4.7%) were identified from the records, of these 77.8% cases had renal impairment and 33.3% presented with rapidly progressive renal failure. The possible explanation is the toxic effects of excess free light chains, in our cohort. The bound LCs show mobility similar to the HC bands on serum immunofixation gels, however the free light chains, exist in polymeric forms and show a different mobility. The identification and reporting of this pattern provides additional information regarding the high load of light chains, and indicates that patient may have a poor renal outcome/performance.