Mesothelioma is often found after a person sees a doctor because of the symptoms they are having. If there is a reason to think you could have mesothelioma, your physician will check you over, and they will run some tests. Symptoms such as coughing and pain in the chest might suggest you have asbestos cancer, but tests must be done to confirm a diagnosis. (Cancer.org)
Take Medical History and Perform Physical Examination
Your doctor will want to discuss your medical history with you to learn more about any symptoms you are experiencing. He or she also will want to know if you have any history of asbestos exposure.
Your doctor will look at you to find signs of other health issues. Pleural mesothelioma affects the lungs and chest cavity. It can lead to fluid building up in the lungs in your chest; this is called a pleural effusion.
In peritoneal mesothelioma, fluid can build in the abdomen, which is called ascites. In pericardial mesothelioma, fluid develops in the sac that envelops the heart, which is called a pericardial effusion. (Stanfordhealthcare.org)
In rare cases, mesothelioma can develop in the testicles and resembles a hernia. All of these signs could be found in a physical examination, such as when your doctor listens to these parts of your body with a stethoscope or taps your bellow or chest with their fingers.
Mesothelioma is notoriously difficult to diagnose. If your medical history results and physical examination suggest you could have cancer, your doctor will need to run more tests. You could need imaging tests, blood tests, and biopsies.
Imaging tests feature X-rays, radioactive particles, sound waves, and magnetic fields to make images of the inside of the body. One or more imaging tests may be used to:
- Review suspicious areas that could be cancerous tumors
- See how far and/or if cancer has spread
- Determine if cancer treatments are working
- Check for signs that cancer has returned after treatment
This is frequently the first test done to check for problems in the lungs and chest. Findings that could indicate mesothelioma is a thickening of the pleura, deposits of calcium on the pleura, fluid in the space between the chest wall and lungs, and changes in the lungs themselves from exposure to asbestos.
A computed tomography scan uses many x-rays to make highly detailed, cross-sectional images of the body. A CT scan can be helpful to look for asbestos cancer to pinpoint the location of cancer. This also can determine the stage of the disease.
For example, the CT scan can show if cancer has metastasized to other organs. This can help to determine if surgery could be a good option. Also, a CT scan can be used to find if chemotherapy is reducing the size of the tumors.
This is an ultrasound performed on the hearts. It can be performed if your physician thinks you could have fluid around your heart (pericardial effusion). This test also is useful to show how well the heart is functioning.
A positron emission tomography scan uses radioactive sugar that is inserted into the blood. The amount of radioactivity is low. Because cancer cells tend to grow rapidly, they absorb more sugar than other cells. A camera then maks a picture of radioactive parts of the body.
The images from a PET scan provide your doctor with a better idea if your pleura is thickening seen on the CT scan is more likely to be scar tissue or cancer. If you have a mesothelioma diagnosis, your physician may opt for this test to see if the mesothelioma is spreading to lymph nodes or other body parts. A PET scan also can be helpful if your physician thinks cancer has spread but he does not know where.
There are machines that can perform a CT and PET scan at the same time. This allows the doctor to look at areas that have more radioactivity on the PET scan with the highly detailed images of that region on the CT scan.
A magnetic resonance imaging scan reveals detailed images of the soft tissues in your body. But an MRI uses radio waves and magnets not x-ray to make images. A contrast material is used called gadolinium that may be injected into one of your veins before the scan to increase detail.
An MRI can show the precise location and extent of the tumor because it shows highly detailed images of soft tissues. For mesothelioma, an MRI can be useful in examining the diaphragm, which is a possible place for cancer to spread.
Doctors run blood tests on people suspected to have cancer because blood levels of some substances are often higher in people with asbestos cancer, including fibulin-3 and soluble mesothelin-related peptides (SMRPs)
Mesothelioma cannot be diagnosed only with blood tests, but high levels of these substances make a mesothelioma diagnosis more likely.
Fluid and Tissue Sample Tests
Your symptoms and test results could strongly indicate you have asbestos cancer. But the diagnosis can only be made by taking cells from an abnormal area and studying them under a microscope, which is called a biopsy.
If there is fluid building up in part of your body because of mesothelioma, a fluid sample can be removed by inserting a thin needle through the skin and into the pocket of fluid. This could be done in your doctor’s office or in the hospital. The procedure has different names depending on where the fluid is located:
- Thoracentesis: Takes fluid from your chest
- Paracentesis: Takes fluid from your belly
- Pericardiocentesis: Takes flue from the area around your heart
The fluid is tested under a microscope to determine if there are cancer cells present. If there are, more tests could be done to see if it is mesothelioma, lung cancer, or something else.
Note: Even even no cancer cells are found, you still could have cancer. Doctors may have to get a sample of the mesothelium tissue to determine if you have mesothelioma.
Small pieces of tumors in the chest may be removed with a needle biopsy. A hollow needle is put through the skin, between your ribs, and into your pleura. A CT scan is used to guide the needle into the suspected tumor so that tiny samples can be taken.
A needle biopsy also can get lymph node samples in the area between the lungs to see if there is cancer there.
An endoscopic biopsy is often used to diagnose asbestos cancer. An endoscope is a tube-like, thin instrument with a camera and light on the end that allows the doctor to look inside the body. Tools can be used with this device to remove tissue samples.
Endoscopes go by different names depending on where they are used:
- Thoracoscopy: Looks inside the chest to examine the pleura and remove samples for biopsies.
- Laparoscopy: Looks inside the belly for any tumors present.
- Mediastinoscopy: This device is inserted between the lungs to determine if cancer has spread to lymph nodes.
All fluid and biopsy samples taken from the body are sent to pathology and tested. A physician looks at them under a microscope to determine if cancer cells are present. If so, he will determine the type of cancer it is.
It can be challenging to diagnose mesothelioma by looking at fluid sample cells. It can even be tough to diagnose mesothelioma from a small needle biopsy. Mesothelioma can resemble other cancers under the microscope.
That is why special lab tests may be done to differentiate mesothelioma from other cancers. If mesothelioma is diagnosed, the pathologies will determine the type and cell type, based on cell patterns seen in the microscope. Mesotheliomas are classified by cell type as epithelioid, sarcomatoid, or biphasic.
Accurately diagnosing mesothelioma takes several types of exams, tests, and diagnostics. Talk to your doctor today if you were exposed to asbestos and have experienced chest pain and/or shortness of breath. The sooner the disease is diagnosed, the better your prognosis.