What Is a Mesothelioma Biopsy?

A mesothelioma biopsy is a medical procedure where a doctor collects a sample of suspected cancer cells for laboratory testing. It is the most accurate way to confirm the presence of cancer. Doctors can mistake mesothelioma for common benign illnesses or other types of cancer. A biopsy is essential for a mesothelioma diagnosis because it can positively identify mesothelioma cancer cells.

In addition to confirming the presence of mesothelioma, a mesothelioma biopsy is necessary to confirm the specific type of mesothelioma a patient has. Mesothelioma can occur in different types of cells. Identifying the type of cell that has become cancerous can help determine the best treatment options and prognosis.

After collecting the biopsy, a doctor sends the biopsied cells to a pathologist, who looks for evidence of cancer in the cells. Because of the tests the pathologist performs, patients may need to wait several days to a week or more to receive biopsy results. Laboratory tests can help determine whether there is cancer and what type of cancer it is, as well as other information about the cancer cells that can help guide treatment.

Diagnosing mesothelioma requires a combination of biopsies, imaging scans and blood tests. The type of biopsy a patient needs depends on the location of the tumor. Pleural mesothelioma affects the lungs and chest and requires a biopsy using video-assisted thoracoscopic surgery. Peritoneal mesothelioma affects the abdomen and typically requires a fine-needle aspiration biopsy.

Mesothelioma Biopsy Facts

Mesothelioma causes the same symptoms as many other diseases — including other cancers. Without a biopsy, doctors can’t rule out mesothelioma. Mesothelioma in different locations can require different types of biopsies.

  • A biopsy is necessary for an accurate mesothelioma diagnosis.
  • Biopsies can sample tumors and lymph nodes for cancer cells.
  • Tissue samples taken with a biopsy can help determine if cancer has spread.

Mesothelioma mostly occurs in the lungs but can also occur throughout the chest, abdomen and other parts of the body. Research shows that being able to visualize the tumor during biopsy and collect a larger sample increases the accuracy of diagnosis.

Endoscopic Mesothelioma Biopsies

Endoscopic biopsies are minimally invasive procedures. This means they aren’t major surgeries but still require general anesthesia. Endoscopic procedures involving the chest usually require an overnight stay — or longer — in the hospital.

A doctor performs an endoscopic biopsy by inserting an endoscope — a long, thin, flexible tube with a light and camera —  into the body through a small incision. Using an endoscope, a doctor can see inside a person’s body, identify suspected cancer cells and collect a tissue sample for testing.

Endoscopic Biopsy Procedure

Endoscopic biopsies can be either outpatient or inpatient procedures. They take 30 minutes to three hours to perform depending on the procedure. Endoscopic procedures involving the lungs are usually performed in an operating room and require a hospital stay.

  1. The patient receives general anesthesia.
  2. The surgeon inserts an endoscope into the chest or abdominal cavity. The camera identifies tissue that appears cancerous for collection.
  3. The surgeon uses a tool to extract tissue samples. Removal of the endoscope may involve sealing an incision, depending upon the procedure.
  4. The patient then goes to a recovery room for monitoring while the anesthesia wears off.
  5. A pathology lab analyzes the tissue sample.

Like all surgical procedures, there is a risk of bleeding, infection or other complications with an endoscopy. Recovering from general anesthesia can take several hours. The patient will likely be groggy, confused and in pain. A short hospital stay is needed to ensure that the patient recovers from the procedure and is well enough to go home. 

The doctor may place restrictions on what activities the patient can perform immediately after going home. They may need to take antibiotics for up to a week after the procedure. Some patients will have stitches that will require removal in one to two weeks.

Types of Endoscopic Biopsies for Mesothelioma

Endoscopy is a powerful tool for looking inside the body without performing major surgery. There are several types of endoscopy doctors use to diagnose mesothelioma depending on the location of the suspected tumor. Some procedures are more complex than others. 

Endoscopy also helps doctors assess the stage of mesothelioma — how large the tumors are and where they have spread. Some clinical trials require that each participant has had a biopsy, chest endoscopy and laparoscopy to ensure a proper diagnosis and determine whether mesothelioma has spread to other parts of the body.

Thoracoscopy and Video-Assisted Thoracoscopy (VATS)

During a thoracoscopy, a surgeon inserts an endoscope between the ribs to remove excess fluid, examine the appearance of the inside of the chest and take tissue samples. VATS is a more involved type of thoracoscopy where a surgeon inserts an endoscope and surgical tools into the chest cavity through small incisions. VATS can collect large samples from multiple sites in the chest.

According to Dr. Jacques Fontaine, with a suspected case of mesothelioma, “we would do a thoracoscopy (also known as VATS) by inserting a small camera between the ribs and taking biopsies — actual little pieces of the tumor from the pleura (lining around the lung). The likelihood of a correct diagnosis with this technique is much higher, more than 95% accurate. Most often it would require general anesthesia and a one-day hospital stay.” This makes VATS an essential tool for diagnosing pleural mesothelioma, especially as an alternative to open surgery.


A surgeon inserts an endoscope at the base of the neck to obtain tissue samples of the lymph nodes around the windpipe. This can help diagnose pleural mesothelioma as well as determine the stage of mesothelioma. A surgeon may perform a mediastinoscopy while the patient is under anesthesia for a thoracoscopy.


The surgeon makes an abdominal incision and then inserts an endoscope. The procedure may require other small incisions to insert surgical instruments. This allows the doctor to examine the abdominal cavity and collect samples of suspicious tissue and fluid in the abdomen (ascites) that a pathologist can test for cancer cells. This procedure is for patients with suspected peritoneal mesothelioma.

Endoscopy and open surgery are not the only way to collect suspected cancer cells, but they can collect large samples of tumors. Doctors also use other less-invasive procedures to diagnose mesothelioma, but these procedures may provide less accurate results.

Fine-Needle Biopsy for Mesothelioma

Percutaneous Needle Core Lung Biopsy: An illustration depicts a needle passing through layers of skin and muscle tissue to enter the lung and extract cellular fluid for a biopsy sample from a target mass.

Fine-needle aspiration is faster and less invasive than endoscopy and also carries fewer risks. It is usually an outpatient procedure without general anesthesia, only local anesthesia. It uses a long, hollow needle attached to a syringe to remove up to 10,000 sample cells for analysis. A doctor will typically use an ultrasound or CT scan to accurately guide the needle to the target.

This type of biopsy is not as good as thoracoscopy for diagnosing pleural mesothelioma, but endoscopy isn’t a safe option for all patients. Fine-needle biopsies can also diagnose peritoneal mesothelioma. They have fewer complications than more invasive procedures, such as endoscopy, but there is always a small risk of infection or bleeding. For lung biopsies, there is a risk of a collapsed lung as well as a small risk of bleeding into the space around the lungs (hemothorax), which can be dangerous. The patient may also cough up a small amount of blood after a lung biopsy — this is normal.

Fine-Needle Biopsy Procedure

A doctor can perform a fine-needle biopsy in a hospital, procedure center or doctor’s office. Depending on individual needs and health conditions, the patient may need to take medication for pain or anxiety before the procedure. Patients should talk to their doctors about this before the biopsy.

  1. The doctor will clean the patient’s skin, apply local anesthesia to the area where they will insert the needle and position the patient so that the doctor can easily perform the procedure.
  2. An ultrasound or CT scan may help determine where to insert the needle. The doctor will then insert the needle into the chest or abdominal cavity to extract tissue. The needle is attached to a syringe that contains a vacuum to collect tissue samples. This procedure typically takes less than 10 minutes.
  3. After removing the needle, the doctor will clean and bandage the incision. The patient will not need sutures.
  4. The doctor will send the tissue samples to a pathology lab for analysis. It could take several days to a week or longer to get results.

The patient can go home after the procedure. Experiencing some pain is normal. Depending on the doctor’s instructions, the patient may take over-the-counter pain medications and will need to limit their physical activity for several days.

Thoracentesis and Paracentesis

Thoracentesis and paracentesis are two other procedures that are not true biopsies, but they are similar. Thoracentesis drains fluid from around the lungs, and paracentesis drains fluid from the abdomen. Using local anesthesia, a doctor inserts a long, blunt needle to drain fluid from pleural effusions in the lungs and ascites in the belly. This helps doctors determine the cause of the excess fluid.

Neither of these procedures can provide an accurate mesothelioma diagnosis, but they can help in the diagnostic process. Many other conditions cause excess fluid buildup around the lungs and in the abdominal cavity, so it is important to rule those out. Removing the fluid also helps relieve symptoms a patient may experience with pleural effusion or ascites such as shortness of breath and abdominal swelling.

Surgical Mesothelioma Biopsies

Doctors do not typically use surgical biopsies to diagnose mesothelioma. However, when an endoscopic or fine-needle biopsy isn’t possible, the patient may require surgery to identify and biopsy tumors. A surgeon performs a surgical biopsy during open surgery, which allows the doctor to clearly see any tumors and collect large samples — including whole tumors.

Types of Surgical Biopsies for Mesothelioma

The type of surgical biopsy a patient needs depends on the location of the suspected mesothelioma.

  • Laparotomy: A laparotomy is an exploratory surgery where doctors open the abdomen. This procedure may help diagnose peritoneal mesothelioma.
  • Thoracotomy: A thoracotomy involves opening the chest cavity or pleural space around the lungs.

When performing a surgical biopsy, the surgeon will usually remove as much of the suspected cancer as possible. This provides a large sample of cancer cells for diagnosis and analysis. It has the highest accuracy rate for mesothelioma diagnosis, but it also carries the greatest risk of complications. 

Surgical biopsies require general anesthesia and large incisions. As with any major surgery, there is a significant risk of bleeding, infection or other complications. Surgical biopsies also require much more recovery time than less-invasive biopsies.

How You Can Prepare for a Mesothelioma Biopsy?

Depending on the type of biopsy you are having, the preparation may vary, but your doctor should give you a detailed list of instructions. According to the Patient Advocates at The Mesothelioma Center, “the doctor will likely ask you to leave valuables at home, remove jewelry and wear comfortable clothing. It’s probable that you will get specific instructions about eating and drinking the night before and/or day of the procedure.”

Your doctor may tell you not to take some or all of your medications before the procedure. Be sure to tell them about every medication you are taking, including over-the-counter drugs and herbal supplements or vitamins. If you are taking a blood thinner (coumadin, heparin, aspirin etc.), you may need to stop taking it temporarily to lower the risk of bleeding during the biopsy.

The following tips can help you prepare for your biopsy:
  • Be sure to follow the doctor’s instructions — especially regarding medications, eating and drinking.
  • If you are receiving general anesthesia, you will most likely need a companion to take you to and from the hospital or clinic. Prepare ahead of time; if you don’t have someone with you, your doctor may not be able to perform the procedure.
  • You may also want to give the doctors and nurses permission to talk to your companion after the procedure. Anesthesia will affect your memory, and you may not remember anything for hours.
  • If you plan to stay in the hospital overnight, be sure to bring a bag with anything you may need (a change of clothes, cell phone charger, etc.).
  • Ask questions about what you need to do after your procedure and when to expect the biopsy results.

One of the most important steps in preparing for a procedure is asking questions — and getting answers. You need to understand the risks and benefits of a biopsy as well as what to expect afterward. You may want to write down any questions you have so you don’t forget them.

If the doctor who has arranged your biopsy is not a mesothelioma specialist, ask who will be reviewing your results. As Dr. Fontaine told The Mesothelioma Center: “The experience of the pathologist reviewing the biopsies is very important. Because it’s so difficult to tell on a microscopic level the difference between cancerous mesothelioma vs. inflamed mesothelial cells or other more common forms of lung cancer, it’s important that the biopsies get reviewed by a hospital or a medical center that has a pathologist who specializes in mesothelioma and examines a lot of samples.” The purpose of a biopsy is to get a correct diagnosis — you want to be sure that you have the right doctors examining the results.

Understanding Your Biopsy Results and Next Steps

After your biopsy, you and your doctor will receive a pathology report with your biopsy results. Mesothelioma biopsy findings can include the subtype of mesothelioma, the size of the tumor(s), whether the mesothelioma has spread and other information. Doctors use this information, along with blood tests and imaging studies, to determine the mesothelioma stage and select the most effective treatment.

You will need to discuss with your doctor what the results mean and what options you have for treatment. Both your doctor and the pathologist should have experience with mesothelioma to interpret the results properly. Communicating well with your doctor is important. You and your loved ones can prepare questions and communication strategies for speaking with doctors about biopsy results and the next steps. 

For some, getting a correct diagnosis of mesothelioma can take a long time. One survivor, Christine S., stated that “for nearly a year I was diagnosed as having pleurisy and pneumonia. Eventually, after lots of tests, x-rays and scans I had my lung drained, but it just filled straight back up again. I had my lung drained again, a VATS procedure and a biopsy.” 

After years of frustration, a diagnosis of mesothelioma was not what she was expecting. Once given her diagnosis, she said, “I had a few tears, but I remember thinking no, keep it together, I have to be strong for my daughter sitting outside and the rest of my family and friends.”
Coping with a mesothelioma diagnosis is a challenge, but it is one you do not have to face alone. The Mesothelioma Center is here to provide the information and support mesothelioma survivors need.