Biopsy Diagnosis

Most often, a procedure known as a biopsy is required for an accurate diagnosis of mesothelioma. There are various types of biopsy procedures, but generally speaking they are used as a means of obtaining a tissue sample from the area in question, so that it can be examined under a microscope. Needle biopsies are one variance of the procedure, which can also be referred to as transthoracic needle aspiration or percutaneous needle aspiration. There are also surgical methods for biopsies.

How is a Biopsy Performed?

Imaging scans, such as an x-ray or CT scan, are usually used in conjunction with a biopsy so that doctors know the exact location from which to remove the tissue sample. A lung needle biopsy can also be performed during bronchoscopy or mediastinoscopy procedures.
During this procedure, the patient sits upright and a local atheistic is injected, after which, a 1/8-inch incision is cut into the skin. At this point the doctor will ask the patient to hold their breath. The incision is made so that the biopsy needle can pass through it, being inserted either into the lung tissue, a tumor, or another abnormality. As the needle is inserted, there can be a sensation of pressure and a sharp pain as the needle reaches the tissue.
This sample tissue is removed and then taken to a lab for further study. Following the biopsy, an x-ray of the chest is generally taken. This procedure ranges from 30 minutes to an hour in length, and results normally take a couple of days.

Test Preparation

Patients are usually asked to refrain from eating 6 to 12 hours prior to their biopsy. Doctors may also advise against patients taking any aspirin, non-steroid anti-inflammatory medications (NSAIDS), or blood thinners prior to the procedure.

Why is the Test Performed?

A lung biopsy is done so that doctors can more accurately diagnose large abnormalities found during previous imaging scans. These biopsies are removed from the abnormality close to the lung’s surface, in the lung itself, or from the chest wall.

Results

A test that comes back as normal means the tissue(s) are normal. An abnormal result could mean one of the following:

• An immune disorder
• Pneumonia
• A presence of cancerous cells, indicative of either lung cancer or mesothelioma
• The presence of either a bacterial, viral, or fungal infection

This type of test can also be done to determine the existence of metastatic cancer in the lungs or for pneumonia within a lung abscess.

Risk Factors

Rarely, a collapsed lung, or pneumothorax, can occur during a lung biopsy. If a pneumothorax does occur, a large tube is inserted in order to re-expand the lung. Although extremely rare, air can escape from the lung and become trapped in the chest, in which case a pneumothorax can be life threatening. A collapsed lung can be indicated by bluish discoloring of the skin, increased heart rate, and shortness of breath. These symptoms following a biopsy should be immediately reported to a doctor.
Needle biopsies are not generally recommended if the patient has:

• Cysts
• Pulmonary hypertension
• Hypoxia
• Blood coagulation disorder
• Certain conditions associated with emphysema

Reference:
American Cancer Society