Imaging and Mesothelioma Diagnosis

Receiving a mesothelioma diagnosis is frightening. However, it is important when suffering from this type of cancer to have an early and accurate diagnosis. Too often diagnoses come too late. Sometimes, patients are diagnosed incorrectly, delaying necessary treatment. Because mesothelioma is difficult to treat, time is of the essence, and treatment must begin as soon as possible.

One important diagnostic tool is imaging. There are methods to image cancerous tissue, but these images also help doctors rule out cancer as a possibility. The most commonly used imaging techniques in diagnosing mesothelioma are X-rays, CT scans, MRIs, and PET scans.

The Importance of Imaging

Imaging is important in diagnosing mesothelioma because it is a safe way of seeing what is inside the body. Blood tests are sometimes inaccurate and exploratory surgery is risky. A clear image of the area can give doctors an idea of whether cancerous tissues are present. Furthermore, these images also help doctors determine where to biopsy. Without images, biopsies are performed blind, making them less effective as a diagnostic tool.

X-Ray

When a patient describes symptoms characteristic of mesothelioma, like pain, coughing, and trouble breathing, a chest X-ray is typically the first imaging scan a doctor will order. An X-ray uses high energy electromagnetic radiation to image dense tissue in the body. Using an X-ray image, the doctor can see if the pleura around the lungs have thickened, an indication of cancer. X-rays also indicate fluid build-up, another type of asbestos-related condition which may indicate mesothelioma.

CT Scan

Computed tomography, or CT scans, also use X-rays. This technique, instead of taking two-dimensional images created with a chest X-ray, takes cross-sectional images of the body.  When receiving a CT scan, the patient lies on a table while the device moves around the body making multiple images. A computer then takes those images and creates detailed cross sections. A radioactive dye, either injected or ingested as a drink, can provide a more detailed image because the dye helps distinguish between finer structures in the body.

CT scans are useful for diagnosing mesothelioma. The image shows abnormal tissue which could be malignant tumors. These scans also help stage cancer, determining how much it has spread to other tissues. CT scans also help doctors determine if treatment is working and the effect it has had on tumor number and size.

MRI

An MRI, or magnetic resonance imaging, creates a picture similar to a CT scan. Instead of X-rays, an MRI uses radio waves to take detailed pictures of the body’s soft tissues. MRI scans typically require a dye to show contrast. However, dye for this procedure is is injected, never ingested. If a patient is allergic to the dye used for CT scans, an MRI is an alternative and vice versa. MRIs are particularly useful for imaging the diaphragm. The diaphragm is often difficult to see in a CT scan because it is located underneath the lungs.

The image produced by an MRI is slightly more detailed than a CT scan. However, an MRI takes significantly longer. To have an MRI, you must lie inside a hollow tube. Because the space is tight, it may not be an option for those who are obese or overweight. The confined space is also problematic for people who may experience anxiety and fear.

PET Scan

Positron emission tomography, or PET scans use a radioactive material to image the inside of the body. First, a radioactive substance is injected into the body. Next, a scanner takes pictures of the radioactivity. The process requires you to lie on a table for about a half an hour. The image is not as clear as a CT or MRI scan, but is useful in other ways.

One important thing a PET scan can determine is whether tissue that appears abnormal is malignant or benign. It can also determine where the cancer has spread because a PET scan produces a whole-body image. The PET scanner can be combined with a CT scan to give your doctor a more detailed and comprehensive image. This combination also produces a three-dimensional image.

Echocardiogram

These imaging techniques are useful for diagnosing and staging pleural and peritoneal mesothelioma. However, they are not useful for diagnosing pericardial mesothelioma, cancer of the lining of the heart. Instead, doctors usually choose an echocardiogram when this type of mesothelioma is suspected. Determining if there is fluid in the lining around the heart, an echocardiogram uses sound waves to image the heart. During a quick and painless echocardiogram, a technician moves a wand over your chest while you lie still.

Imaging Goes Beyond Diagnosis

These imaging techniques are crucial for a complete mesothelioma diagnosis. However, they are useful for much more than that. If you have mesothelioma, scans can help your doctor stage the cancer. The images also allow your doctor to see how far the cancer has spread, as well as how large the tumors are in the original location.

Images also track cancer progression and treatment. If you have surgery, chemotherapy, or radiation, an imaging scan can show how successful that treatment has been. Because they allow your doctor to see the progress of the treatment, these images also influence the next step of cancer treatment.

Imaging is an important diagnostic, staging, and tracking technique. Your doctor will choose the type of image best suited for your situation including using a combination of images to get the best result. As technologies develop, doctors are likely to have more imaging options for mesothelioma patients.