Medicine

Serum protein electrophoresis (SPEP) test and cancer. When to perform it?

Serum protein electrophoresis (SPEP) test is often used in the diagnosis and monitoring of various diseases, including neoplastic diseases. What is it exactly? When should it be done? What determines the interpretation of the result? Answers to all these are in the article below.

Serum protein electrophoresis — what is it?

Serum protein electrophoresis is a laboratory test that allows to obtain information helpful in the diagnosis of cancer, hematological diseases and chronic inflammation, and diseases related to liver and kidney disorders, as well as deficiencies of various causes. SPEP test uses the ability of proteins to migrate in an electric field. The result of this test is the division of the protein into 5 or 6 protein groups, which are then subjected to a detailed analysis.

Proteins have many very important functions, including being a significant part of the plasma. Thanks to this, they are an excellent indicator in the diagnosis of health. Protein electrophoresis allows for a detailed analysis of individual protein groups, the concentrations of which may change as a result of health issues in the body.

Serum protein electrophoresis — when should it be done?

SPEP test verifies the results of other laboratory tests, as a part of diagnostics of inflammation, autoimmune diseases, and monitoring of blood proliferative diseases (e.g. multiple myeloma, lymphoma, leukemia). This test is performed to obtain information about how the disease effects on the protein production in the patient’s body. Usually, additional tests are required to identify the immediate cause of the disease.

The doctor may refer a patient to serum protein electrophoresis in case of such symptoms:

Weakness;
Persistent fever;
Increased thirst;
Frequent urination;
Bone pain;
Increased bone fragility;
Back pain;
Recurring infections, herpes, thrush;

The basis for performing SPEP tests are symptoms that may indicate neoplastic diseases, blood proliferative diseases, autoimmune diseases, chronic inflammation, kidney diseases (e.g. glomerulonephritis), liver damage, chronic infections.

SPEP test — how is it performed?

In order to perform a serum protein electrophoresis, it is necessary to take a blood sample from the patient. This test can also be performed with urine or cerebrospinal fluid samples. In the first step, serum sample obtained from the patient's blood is transferred onto agarose gel. The sample prepared in this way is next placed in the analyzer. Then, thanks to maintaining a constant voltage and temperature, protein starts to separate. After a proper period of time, the sample is removed and then stained. The dye binds to proteins in proportion to their concentration. The last step is analysis of the coloration degree of separated proteins.

SPEP test — what is the waiting time for the result?

The waiting time for the result is one to two weeks after the patient's sample is taken.

SPEP test— interpretation of the result

The test is performed to detect and monitor kidney and liver diseases, as well as bone marrow and cancer. SPEP test is usually performed if the total protein test result is abnormal. In this case, serum electrophoresis is an extension of the diagnosis. The result of the serum protein electrophoresis test shows the percentage values of the individual protein fractions, as well as their concentration.

Serum protein electrophoresis interpretation should be performed by the specialist who performed the test.

Change

What could it mean?

Uniform reduction in the level of all proteins (with the percentage of individual fractions unchanged)

This change suggests severe malnutrition or high blood loss

Increase in albumin concentration

The most common cause of such a change is dehydration

Drop in albumin levels (hypoalbuminaemia)

It testifies to malnutrition, malabsorption disorders, it occurs as a result of liver and kidney diseases, as well as in cancer

A decrease in the concentration of alpha-1 globulins

Observed in pregnancy, liver disease, congenital antitrypsin deficiency and malnutrition

Increase in the concentration of alpha-1 and alpha-2 globulins

It results from acute inflammation

Lack of alpha-1 globulin fractions

The cause is hereditary deficiency of alpha-1-antitrypsin. 4.

Increase in beta-globulin concentration

It usually results from an increase in LDL cholesterol and disturbances in the lipid profile as well as transferrin and anemia (iron deficiency), as well as the presence of cancer.

A decrease in the concentration of beta-globulins

It may indicate blood clotting disorders, intestinal inflammation, malnutrition, digestive and absorption disorders, hyperthyroidism and liver damage

Increase of gamma-globulin fractions (antibodies)

It appears as a result of chronic inflammation and autoimmune diseases, as well as liver damage and cancer

No gamma-globulin band (antibodies)

It proves the primary immunodeficiency resulting from the lack of antibodies

Decrease in the levels of gamma-globulins (antibodies)

The cause of the change may be diseases damaging B lymphocytes; it also occurs during immunosuppressive therapy and steroid therapy

Appearance of a narrow, highly saturated band within gamma or betaglobulin

Characteristic for monoclonal gammapathies — usually multiple myeloma

Increase in the concentration of alpha -2 and beta-globulins with a decrease in gamma-globulins and albumin

Usually characteristic of nephrotic syndrome, a kidney disease associated with loss of protein.

The appearance of a ‘bridge’ between the beta and gamma-globulin fractions with a reduction in the content of albumin, alpha-1 and -2 globulins

It appears in patients with cirrhosis of the liver

Serum protein electrophoresis and cancer

Some neoplastic diseases cause changes in the concentration of individual protein fractions. Serum protein electrophoresis plays an auxiliary role during oncological diagnostics. This examination, in combination with others, allows to obtain a complete picture about the health of a patient along with the developed health issues. In case of advanced cancer, a decrease in protein is often observed, and thus also the concentration of albumin (the main plasma protein) is lower. SPEP test is most commonly used in the diagnosis and monitoring of myeloma as well as some lymphomas.