One of the first methods of detecting mesothelioma doctors use is image scanning technology, such as an X-ray, MRI, CT scan, or PET scan. These tools are the least invasive, and usually the least expensive, of all mesothelioma diagnostic tests.
It is important to understand that imaging tests alone cannot diagnose mesothelioma. They can, however, provide useful information about whether a tumor exists, if it has spread, and how difficult it might be to obtain a biopsy or perform surgery – all of which is useful for staging the disease upon diagnosis.
Mesothelioma Imaging Quick Facts
- X-rays are good for detecting certain mesothelioma symptoms, like pleural or peritoneal effusions (fluid buildup).
- CT scans are about 90% effective at detecting pleural mesothelioma.
- MRI scans have the highest resolution and can show if the cancer has spread (metastasized).
- PET scans show cancer cell metabolic activity, which can aid the determination of a patient’s prognosis.
When are Imaging Scans Performed?
Imaging tests are used to detect and diagnose a number of diseases and medical conditions. When a patient begins to experience symptoms of mesothelioma, as part of the initial physical examination, a doctor may order an X-ray or another type of scan to get a view of what is happening within the body.
While diagnosis is the primary use for imaging scans, they can also be used for other purposes, such as mesothelioma staging. For example, MRI scans provide high-resolution 3D model images, which can be useful for seeing whether the mesothelioma has metastasized (spread), an indication that the disease has reached Stage 3 or Stage 4.
Types of Mesothelioma Imaging Tests
There are four primary types of imaging tests used during the mesothelioma diagnosis process. Each of these tests has advantages and limitations.
An X-ray is a radiographic image used in diagnostic evaluation of bones and soft tissue. X-ray exams are frequently used by doctors as a first-level diagnostic tool to understand what is going on in a particular area of the body and to identify whether additional testing is needed.
A chest X-ray is the most common use of X-rays in medicine, and it is a common tool for diagnosing pleural mesothelioma. When an individual exhibits troubled breathing along with chest pain, an X-ray may be used to rule out infections like pneumonia or bronchitis, and it could reveal effusion (fluid buildup) or the presence of a tumor.
For peritoneal mesothelioma, X-rays of the abdomen may uncover an obstruction or blockage of the bowels and intestinal tract, which could indicate the presence of a tumor.
While X-rays are useful for medical diagnosis, they have limited capabilities. For example, due to the relatively low resolution of the images, X-rays are typically unable to detect whether the cancer has metastasized.
MRI (Magnetic Resonance Imaging)
MRI uses magnetic fields, radio waves, and computer imaging to construct 3D images of selected areas within the body. MRI images tend to be much clearer than X-rays and CT scans, and they are usually able to show a contrast between cancerous tissue and healthy tissue. As such, MRI images are used as an important diagnostic tool to detect the presence of mesothelioma and identify the stage of the cancer.
As a diagnostic technique, MRI scans allow physicians to verify the presence of cancerous tumors or cells. They can also show the location of the tumors to perform additional diagnostic tests, such as biopsies.
As a staging tool, a physician may examine an MRI to determine the exact location of the cancer to assign a staging and treatment protocol. In patients who are candidates for surgical resection, the MRI allows surgeons to determine the exact location and extent of the cancerous cells to create a treatment plan.
For many, an MRI is not an entirely comfortable procedure. While the procedure itself is not invasive, it often involves an extended period of lying down within a small, enclosed space. Newer MRI machines are designed to make patients more comfortable and feel less claustrophobic during the scan. In many cases, relaxing music is played to help patients stay at ease during the procedure.
CT (Computed Tomography)
A CT scan (sometimes called a CAT scan for “computer-assisted tomography”) provides images of the same location from many different angles to create a 3D model of the scanned area. In many cases, CT scans are useful in helping doctors diagnose both pleural and peritoneal mesothelioma.
CT scans is a computed image of the internal tomography of an individual. The CT machine is a donut-shaped device than can be positioned to scan the affected area. CT scans use a series of X-ray images, so precautions regarding radiation exposure are always taken. Due to the dangers posed by radiation, CT scans are rarely used to diagnose pericardial mesothelioma.
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Like MRI scans, CT scans produce high-contrast images of the affected areas to clearly show differences between healthy tissue and cancerous masses. However, because CT scans use X-rays, they may not be quite as clear as MRI images. Still, they can be a useful diagnostic tool used by mesothelioma doctors.
PET (Positron Emission Tomography)
As a nuclear imaging technology, PET scans use a completely different process than other imaging types. Specifically, the patient will ingest a radioactive, glucose-based tracer that can be detected by a scanning machine. Fast-growing cancer cells will absorb more of the glucose due to their higher metabolic activity, allowing the PET scanner to distinguish between healthy tissue and cancerous tumors.
With mesothelioma, PET scans can be used to stage the cancer and to determine the viability of certain cancer treatments. For example, if a patient is undergoing chemotherapy, a PET scan can display damaged tissue. The scan is useful for staging mesothelioma by detecting the advancement of the disease. If other surrounding tissue is affected, then the scan will produce an image of the metastasis.
A PET-CT scan uses the features of both PET and CT scans to provide enhanced images of the disease. For late-stage mesothelioma, this hybrid may be a critical tool to view and evaluate the advancing cancer.
Costs of Imaging Scans
Although imaging tests are generally the least costly of the diagnostic tools mesothelioma doctors uses, they can still be expensive. Even in the early stages of detecting the disease, the bills can build up quickly as each additional test needs to be performed.
The good news is that financial assistance for your imaging tests may be available for those are eventually diagnosed with malignant mesothelioma due to asbestos exposure. If you or a loved one have received such a diagnosis, contact an expert to find out what options may be available for you.
Author: Linda Molinari
Editor in Chief, Mesothelioma Cancer AllianceRead about Linda
Reviewer: Annette Charlevois
Patient Support CoordinatorRead about Annette
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