Diagnosis

Diagnosis is the process of determining the kind of disease that is present. An accurate diagnosis is important because it helps to determine the type of treatment that you will undergo.

Your doctors may use a number of procedures to aid in the diagnosis of mesothelioma. The most common of those procedures are listed here. Whether one or a combination of these tests are conducted in a given patient’s case will depend on factors unique to the patient. Some tests might first be conducted to determine whether a biopsy should be performed. A biopsy is usually necessary to confirm a diagnosis.

For your reference, a word with “-scopy” at the end refers to the use of a scope or viewing instrument that can be used to look directly inside the body at the abnormal or suspected area. A word that ends in “-ectomy” refers to the removal of tissue through surgery.

Pleural Mesothelioma: Diagnosis

Your doctor may perform some of the following procedures to diagnose pleural mesothelioma.

CT scan

This type of X-ray provides a very detailed picture of the size and location of the cancer. The images taken are compiled by a computer to create a more complete image of the disease. The procedure is also called a computerized axial tomography (CAT) scan.

PET scan

A procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is used. Because cancer cells often use more glucose than normal cells, the pictures can be used to find cancer cells in the body.

Thoracoscopy

The diagnosis of malignant pleural mesothelioma may involve your doctor looking inside the chest cavity with an instrument called a thoracoscope. For this procedure, an incision is made through the chest wall and the thoracoscope is put into the chest between two ribs. This procedure is usually done in the hospital.

Bronchoscopy

A bronchoscopy involves an examination of the lungs and air passages. The doctor places a lighted tube down the patient’s throat and trachea into the lungs. This procedure is called a bronchoscopy, and the instrument used is called a bronchoscope.

Thoracentesis

Some patients develop fluid in their lungs. This is called a pleural effusion. Your doctor might take a sample of this fluid with a needle injected into the chest and test the fluid for cancer cells. Your doctor may also perform this procedure for draining fluid from the lungs to help relieve pain.

Mediastinoscopy

This is a test that examines the mediastinum. This area is in the center of your chest, between your lungs, and contains the heart, blood vessels and lymph nodes.

Needle Biopsy

For this procedure, the doctor uses a thin needle to take samples of cells for examination under microscope. This test can be uncomfortable but may take only a few minutes. Small pieces of the tissue are taken and then sent to a laboratory for analysis.

The doctor might also use an X-ray, CT scan or fluoroscopy to guide the needle as it is inserted into the tumor. Fluoroscopy is a diagnostic procedure in which X-rays are passed through the body and then projected onto a screen, providing a continuous image of the body’s internal structures.

Wedge Biopsy

For this procedure, a doctor makes an incision through the skin, and a wedge of tissue or tumor is obtained and sent to a laboratory for analysis. A wedge biopsy is often used when other biopsy methods have been unable to confirm a diagnosis.

Cytology and Pathology

Pathology is a study of a disease, which looks at specific cells and types of a disease process to determine the cause. Pathology tests are performed on samples of body fluid or tissue to determine the cell type (cytology) of a specific disease. The process of looking at these samples may include using microscopes, electron microscopes and various stains. This refers to special cell-staining techniques that identify specific types of malignant mesothelioma tumors. Certain types of dyes or coloring are added to the patient’s biopsy samples. Depending on how the tissue responds to the dye, the doctor can make a better estimate about the outcome of the illness. In making the diagnosis, the more information the doctor has about the tumor, the better he or she can recommend appropriate treatment.

After your biopsy, a sample of the tissue or fluid removed may be sent to a hospital laboratory to be analyzed.

• If fluid is removed during a thorancentesis or thorascopy, it is sent to a Cytology lab for analysis. Your doctor will receive a written report of the results. The doctor may receive an oral report from the lab prior to the written results.

• If a tissue biopsy from a bronchoscopy, needle biopsy or thorascopy is done, it is sent to a surgical pathology lab for analysis. The final report will be sent to your doctor.

• Surgical removal of a tumor, pleura or lung is sent to a surgical pathology lab. In the lab the material is analyzed with special stains. The material may be placed under a microscope for magnification and further review to determine the cell type. After analysis is completed, small pieces of any remaining tissue are preserved in paraffin for future us

Peritoneal Mesothelioma: Diagnosis

One way doctors diagnose peritoneal mesothelioma is by looking inside the abdominal cavity with an instrument called a peritoneoscope. In this procedure, a cut is made through the abdomen wall and the peritoneoscope is placed into the abdomen. This test, called a peritoneoscopy, is usually performed in the hospital. Some patients develop excessive fluid in the abdomen. This is called an effusion or ascites. A doctor may take a sample of such fluid to diagnose peritoneal mesothelioma.

Pericardial Mesothelioma: Diagnosis

Pericardial mesothelioma is also known as mesothelioma of the pericardium or cancer of the sac that holds the heart. Your doctor may diagnose pericardial mesothelioma using a thoracoscope to perform a thoracoscopy, which might also involve opening up the chest cavity to remove the tumor.

Patients who develop excessive fluid around the heart, called an effusion, may have a sample of the fluid taken to diagnose pericardial mesothelioma.