From the Guidelines
To determine if multiple myeloma has relapsed, I recommend ordering serum and urine protein electrophoresis with immunofixation, serum free light chain assay, complete blood count, comprehensive metabolic panel, and serum calcium levels, as well as considering imaging studies such as low-dose whole-body CT, MRI, or PET-CT, as outlined in the 2017 Mayo Clinic Proceedings guidelines 1.
Key Tests for Relapse Detection
- Serum and urine protein electrophoresis with immunofixation to detect monoclonal protein (M-protein) produced by malignant plasma cells
- Serum free light chain assay, particularly useful for monitoring light chain myeloma
- Complete blood count to assess for anemia, leukopenia, or thrombocytopenia
- Comprehensive metabolic panel to evaluate renal function and electrolyte imbalance
- Serum calcium levels to detect hypercalcemia
Imaging Studies for Relapse Detection
- Low-dose whole-body CT to assess for new bone lesions
- MRI to evaluate bone marrow involvement and soft tissue disease
- PET-CT to detect metabolically active lesions
Additional Tests for High-Risk Disease
- Bone marrow biopsy with fluorescence in situ hybridization (FISH) studies to evaluate cytogenetic abnormalities
- Gene expression profiling to understand disease behavior and guide therapy
- Flow cytometry to detect circulating clonal plasma cells These tests should be compared to the patient's previous baseline values, and rising M-protein levels, increasing free light chain levels, new bone lesions, worsening anemia, hypercalcemia, or renal dysfunction compared to previous stable values strongly suggest disease relapse, as noted in the 2011 Blood study 1. Early detection of relapse allows for prompt initiation of salvage therapy, potentially improving outcomes before clinical symptoms develop.
From the Research
Tests for Determining Multiple Myeloma Relapse
To determine if multiple myeloma has relapsed, several tests can be ordered. These include:
- Serum protein electrophoresis (SPEP) 2, 3, 4
- Urine protein electrophoresis (UPE) 5, 3, 6
- Serum free light chain test 5
- Immunofixation electrophoresis (IFE) 6, 4
- Bone marrow biopsy with immunohistochemical analysis 3
Sensitivity and Specificity of Tests
The sensitivity and specificity of these tests vary:
- Serum free light chain test has been shown to be more sensitive than urine electrophoresis for monitoring multiple myeloma 5
- SPEP and UPE can be used to screen patients for residual disease, and negative results for both can obviate the need for bone marrow biopsy for the detection of residual disease by immunohistochemical analysis 3
- Immunofixation electrophoresis detection technique can increase the diagnosis accuracy in patients with atypical multiple myeloma 4
Clinical Utility
The clinical utility of these tests is as follows:
- Serum protein electrophoresis is an easy to perform laboratory test which can be used for detection and quantification of monoclonal gammopathy and should be recommended as preliminary test for suspected cases of multiple myeloma 2
- Urine immunofixation is not necessary for defining complete response in multiple myeloma patients other than those with light-chain-only disease 6