What is the management approach for a patient with abnormal Serum Protein Electrophoresis (SPEP) results?

From the Guidelines

Management of a patient with abnormal Serum Protein Electrophoresis (SPEP) results requires a systematic approach based on the specific pattern identified, with initial management including a thorough clinical evaluation and additional testing such as immunofixation electrophoresis, serum free light chain assay, and bone marrow biopsy if indicated, as recommended by the most recent guidelines 1.

Initial Evaluation

The initial evaluation of a patient with abnormal SPEP results should include a thorough clinical evaluation to determine the underlying cause, followed by appropriate additional testing. This may include:

• Immunofixation electrophoresis to identify the type of monoclonal protein present
• Serum free light chain assay to assess the level of free light chains in the serum
• Complete blood count and comprehensive metabolic panel to evaluate for any signs of anemia, renal impairment, or other systemic abnormalities
• Bone marrow biopsy if indicated to assess for plasma cell infiltration and other abnormalities

Monoclonal Gammopathies

For patients with monoclonal gammopathies, further workup should include:

• Serum protein electrophoresis (SPEP) and serum immunofixation electrophoresis (SIFE) to obtain more specific information about the type of abnormal antibodies present
• Urine analysis, including 24-hour urine protein electrophoresis (UPEP) and urine immunofixation electrophoresis (UIFE) to evaluate for the presence of monoclonal protein in the urine
• Skeletal survey or advanced imaging (low-dose CT, MRI, or PET-CT) if multiple myeloma is suspected

Monitoring and Treatment

For patients with monoclonal gammopathy of undetermined significance (MGUS), regular monitoring is recommended with repeat SPEP every 6-12 months initially. Patients with more concerning findings such as elevated M-protein (>1.5 g/dL), non-IgG isotype, or abnormal free light chain ratio should be monitored more closely. For confirmed multiple myeloma requiring treatment, referral to hematology-oncology is necessary for specific therapy regimens, as outlined in the guidelines 1. Some key points to consider in the management of patients with abnormal SPEP results include:

• The importance of using the same test for serial studies to ensure accurate relative quantification
• The use of serum free light chain assay to monitor disease response and progression in patients with non-secretory myeloma
• The role of bone marrow aspiration and biopsy in detecting quantitative and/or qualitative abnormalities of bone marrow plasma cells
• The importance of evaluating for lytic bone lesions using full skeleton radiographic survey or advanced imaging.

From the Research

Management Approach for Abnormal Serum Protein Electrophoresis (SPEP) Results

The management approach for a patient with abnormal Serum Protein Electrophoresis (SPEP) results involves several steps, including:

• Evaluation of patients with possible multiple myeloma, which includes measurement of hemoglobin, serum creatinine, serum calcium, and serum free light chain levels; serum protein electrophoresis with immunofixation; 24-hour urine protein electrophoresis; and full-body skeletal imaging with computed tomography, positron emission tomography, or magnetic resonance imaging 2
• Identification of monoclonal gammopathies, which are associated with a clonal process that is malignant or potentially malignant, including multiple myeloma, Waldenstrom's macroglobulinemia, solitary plasmacytoma, smoldering multiple myeloma, monoclonal gammopathy of undetermined significance, plasma cell leukemia, heavy chain disease, and amyloidosis 3
• Use of immunofixation electrophoresis detection technique, which can be used for screening M protein in patients with atypical multiple myeloma and can increase the diagnosis accuracy in patients with atypical multiple myeloma 4

Diagnostic Techniques

Diagnostic techniques used in the management of abnormal SPEP results include:

• Serum protein electrophoresis, which separates proteins based on their physical properties and can identify patients with multiple myeloma and other serum protein disorders 3
• Immunofixation electrophoresis, which can detect M protein in patients with multiple myeloma and can increase the diagnosis accuracy in patients with atypical multiple myeloma 4
• Serum free light chain measurements, which can provide greater sensitivity than urine electrophoresis for monitoring response to therapy in patients with multiple myeloma 5
• Urine immunofixation electrophoresis, which can benefit diagnosis of multiple myeloma in orthopedic patients with normal serum total proteins, creatinine, calcium, and hemoglobin 6

Treatment Options

Treatment options for patients with abnormal SPEP results include:

• Standard first-line (induction) therapy, which consists of a combination of an injectable proteasome inhibitor, an oral immunomodulatory agent, and dexamethasone, and is associated with median progression-free survival of 41 months 2
• Autologous hematopoietic stem cell transplantation, which is standard of care for eligible patients with multiple myeloma 2
• Maintenance therapy with lenalidomide, which is considered standard care for eligible patients with multiple myeloma 2