Soluble Mesothelin-Related Peptides

At a Glance

Why Get Tested?

To monitor progression or recurrence of a rare cancer called mesothelioma; this cancer affects the membranes that surround the lungs, heart, and abdominal cavity. Most cases of mesothelioma are associated with asbestos exposure.

When To Get Tested?

After you have been diagnosed with mesothelioma, this test may be requested to follow response to treatment at anytime during or after treatment.

Sample Required?

A blood sample taken from a vein in the arm.

Test Preparation Needed?

None

On average it takes 7 working days for the blood test results to come back from the hospital, depending on the exact tests requested. Some specialist test results may take longer, if samples have to be sent to a reference (specialist) laboratory. The X-ray & scan results may take longer. If you are registered to use the online services of your local practice, you may be able to access your results online. Your GP practice will be able to provide specific details.

If the doctor wants to see you about the result(s), you will be offered an appointment. If you are concerned about your test results, you will need to arrange an appointment with your doctor so that all relevant information including age, ethnicity, health history, signs and symptoms, laboratory and other procedures (radiology, endoscopy, etc.), can be considered.

Lab Tests Online-UK is an educational website designed to provide patients and carers with information on laboratory tests used in medical care. We are not a laboratory and are unable to comment on an individual's health and treatment.

Reference ranges are dependent on many factors, including patient age, sex, sample population, and test method, and numeric test results can have different meanings in different laboratories.

For these reasons, you will not find reference ranges for the majority of tests described on this web site. The lab report containing your test results should include the relevant reference range for your test(s). Please consult your doctor or the laboratory that performed the test(s) to obtain the reference range if you do not have the lab report.

For more information on reference ranges, please read Reference Ranges and What They Mean.

What is being tested?

This test measures the quantity in the blood of a small molecule called mesothelin-related peptides (SMRP). These peptides are breakdown products from proteins found in the membranes lining the cavities that surround the lungs, heart, and abdomen. Large amounts of SMRP are often seen in the blood of patients suffering from mesothelioma, and the amount of SMRP in the blood is thought to be related to the extent of the disease.

Malignant mesothelioma is a rare cancer of the membranes that cover the outside of internal organs and line body cavities, including the chest (pleural mesothelioma), abdominal cavity (peritoneal mesothelioma), and the heart (pericardial mesothelioma). Pleural mesothelioma is the most common type, accounting for 90% of all cases. Most cases of pleural mesothelioma (70%-80%) arise in patients with a history of working with asbestos, especially in the shipbuilding, construction, automotive, and fireproofing industries. The disease has a long latency period, meaning that patients usually develop mesothelioma 20 to 50 years after asbestos exposure.

Common Questions

How is it used?
This test is limited to patients who have already been diagnosed with malignant mesothelioma. It is not used to diagnose the disease. This test is most often used in conjunction with imaging tests such as positron emission tomography (PET) and computed tomography (CT) to:

determine if you are responding to treatment,

see if the disease has spread,

determine if the disease has returned after you have been treated.
When is it requested?
A doctor might request a series of SMRP tests to monitor progression of mesothelioma or its recurrence;

after you have been diagnosed,

after you have had surgery to remove tumour tissue in the chest cavity,

during and/or after chemotherapy or radiation therapy.
What does the test result mean?
If a series of blood tests show that SMRP concentrations are increasing, it may indicate that mesothelioma has progressed. If the series of tests indicate that SMRP concentrations are decreasing, you may be responding to therapy. If the concentrations remain unchanged, it may mean that your disease has stabilised

The interpretation of your SMRP test results will likely be done in conjunction with results from imaging studies. That’s because;

the test does not always provide doctors with useful information. Patients with other cancers - including lung, ovarian endometrial, and pancreatic cancers - can have apparent elevated SMRP test results as a result of their cancers producing substances that interfere with the test.

some patients with epithelial mesothelioma, a form of the disease that affects the cavity lining or membranes, do not produce SMRP.
Is there anything else I should know?

This test is not used to screen for or diagnose mesothelioma but only used to monitor disease progression, regressionor recurrence. The diagnosis of this disease is often difficult and involves many steps. It usually begins with a review of the patient’s medical history, including a history of exposure to asbestos, and with a complete physical examination. These may be followed by imaging studies of the chest and abdomen, including X-rays and computed tomography (CT) scans, and with lung function tests. Diagnosis may be confirmed by examining tissue from a biopsy or fluid from the affected area for malignant cells.
What is asbestos and how does it cause mesothelioma?

Asbestos is a heat- and fire-resistant insulating material that was widely used in construction, shipbuilding, and the automotive industry after 1945 through the 1970s. Workers breathed in the tiny fibres that comprise asbestos. Those fibres entered their pleura, the lining of the chest cavity and lung, and damaged its cells. Mesothelioma develops over a long period of between 15 and 60 years after exposure to asbestos Research has also shown that family members and others living with workers exposed to asbestos are at an increased risk of developing mesothelioma.

There is currently no reliable screening test for mesothelioma.