Early symptoms of mesothelioma can appear non-specific to both a patient and his or her doctor, and may lead to a delay in diagnosis. The symptoms can include pain in the lower back or at the side of the chest and shortness of breath. Less often, an individual can experience trouble swallowing, cough, fever, sweating, tiredness, and weight loss. Symptoms of peritoneal mesothelioma (affecting the lining of the abdominal cavity) include belly pain, weight loss, nausea and vomiting. Minor ailments can often cause these same symptoms. Sometimes resembling viral pneumonia, pleural mesothelioma (affecting the lining of the lungs) patients may suffer shortness of breath, chest pain and persistent cough. Some patients show no symptoms at all. Pleural effusion, or an accumulation of fluid between the lining of the lung and the chest cavity, represents one of the most common symptoms of mesothelioma. As the volume of fluid increases, shortness of breath, known as "dyspnea", and sometimes pain may occur. If you have worked with asbestos and you have any of these symptoms, you should see your doctor right away.
If reasons exist to suspect you might have Mesothelioma (particularly exposure to asbestos), a doctor will take your medical history and do a complete physical exam. Then the doctor can use one or more of the methods described below to determine if the disease is present.
A doctor diagnoses mesothelioma through a careful assessment of clinical and radiological findings proceeded by a confirming tissue biopsy. The doctor should review the patient's medical history, including history of asbestos exposure, followed by a complete physical examination, x-rays of the chest or abdomen, and lung function tests. The doctor may also order a CT scan or MRI at this time. If any of these preliminary tests indicate the presence of mesothelioma, a biopsy is performed to confirm this diagnosis.
A doctor may use a needle biopsy of the mass, or the removal and examination of the fluid surrounding the lung for diagnosis. Because these samples are sometimes inadequate as far as determining cell type (epithelial, sarcomatous, or mixed) or because of the unreliability of fluid diagnosis, a doctor may recommend open pleural biopsy. In a pleural biopsy procedure, a surgeon makes a small incision through the chest wall and inserts a thin, lighted tube called a thoracoscope into the chest between two ribs. The surgeon then removes a sample of tissue that a pathologist will review under a microscope. In a peritoneal biopsy, the doctor makes a small incision in the abdomen and inserts a peritoneoscope into the abdominal cavity. The following represents a list of diagnostic procedures that a doctor may use to determine whether mesothelioma exists.
Imaging tests allow doctors to see a picture of the area in question. These could include x-rays, CT scans (computed tomography), or MRI (magnetic resonance imaging).
A bronchoscopy or a mediastinoscopy uses a lighted tube to let the doctor look at the affected area.
Cytology tests the pleural fluid for malignant cells after doctors remove it using a needle. Medical experts consider this test to have limited value in diagnosing mesothelioma, because negative or inconclusive readings account for nearly 85 percent of all fluid tested. Even with a positive fluid report, many doctors prefer to perform a confirming tissue biopsy as long as it does not compromise the patient's health. Fluid samples may be taken with a needle and sent to the lab to see if cancer cells are present.
A doctor can perform a thoracoscopy or a laparoscopy to look directly at the tumor and to take a sample of tissue that a pathologist then examines. In these procedures, a doctor makes a small incision and uses a tiny video camera to look at the area in question.
During a needle biopsy, done under local anesthetic, a doctor inserts a large hollow needle through the skin and into the chest cavity. The doctor then rotates the needle and as the needle is taken out, the doctor can collect tissue samples. Because of the small sample size of the tissue, experts consider this type of biopsy to be only 25 to 60 percent accurate in diagnosing mesothelioma.
Experts consider the open biopsy the most accurate for mesothelioma diagnosis. It is the procedure of choice because it affords the pathologist a larger tissue sample. Surgeons perform open biopsies in hospitals under general anesthetic.
A doctor may want to do other tests as well. Doctors often encounter difficulties in diagnosing mesothelioma. In some cases a pathologist may use an electron microscope to look at cells in greater detail. If after thorough review a pathologist confirms a diagnosis of mesothelioma, the doctor may want to do further testing such as a PET scan to learn the stage or extent of disease. Knowing the stage helps the doctor form a treatment plan.