Mesothelioma Facts 11-20

11. What kinds of tests might the doctor order to see if I have mesothelioma?

X-rays, CT scans, and MRI scans are the most useful tests at the beginning, trying to decide what your diagnosis is. Pleural mesothelioma is easier to diagnose then peritoneal mesothelioma.

An X-ray is a type of high energy radiation. Low doses of X-ray energy are used to take pictures, or generate images, of parts of the body, and to diagnose disease. High doses of the same type of energy can be used to treat cancer. This is called radiation therapy.

A CT scan (also called a CAT scan) is a specific type of computerized X-ray. CT stands for Computed Tomography. The machine taking the X-rays rotates around the patient, and by doing so is able to generate a three-dimensional picture of the body, in “slices.” One set of scans will be done, and then the patient may be given a “contrast agent” by vein - a substance that will help outline and delineate different parts of the body.

When trying to evaluate a patient with an abnormal chest X-ray, doctors will usually order a CT scan because it provides much more information. What looks like an area that could be fluid or pneumonia on plain X-
ray may be more clearly seen as separate tumor and/or fluid. Masses in the middle of the chest near the heart are almost impossible to see on plain X-ray, but CT scan can delineate masses in what that area, called the hilum.

CT scans can also be useful in diagnosing peritoneal mesothelioma, by getting the three-dimensional pictures of the abdomen, looking for abnormal masses or fluid. Since a CT scan can often give a picture of the tumor, it can also give an indication of its size and if it appears to have spread. A CT scan may give doctors the information they need to decide where to attempt to take a biopsy.

An MRI can also be useful in evaluating a patient who may have mesothelioma. MRI stands for Magnetic Resonance Imaging. It uses radio waves and magnets to generate images, but no radiation. Like a CT scan, this can be done with or without intravenous contrast material. MRI’s are the best imaging scans to look
at the diaphragm, the muscle between the chest and abdomen, which is often involved in mesothelioma.

Your doctor will also order a set of blood tests to see how the systems in your body are working. You could have a low blood count because of the tumor. Other areas of the body could be affected. With a pleural mesothelioma, if your doctor does tests to check you lung function, they will probably be abnormal. With
abdominal mesothelioma, your doctor might find evidence of problems in your liver or kidneys because the tumor is near them. All of this information can be helpful but will not make the diagnosis.

The most important thing is for the scans to give the doctor an idea of where to go to take a sample of tissue for a biopsy.