When is endoscopy used?

Endoscopes were first developed to look at parts of the body that couldn’t be seen any other way. This is still a common reason to use them, but endoscopy now has many other uses too. It’s often used in the prevention, early detection, diagnosis, staging, and treatment of cancer.

To prevent and screen for cancer

Some types of endoscopes are used to look for cancer in people who have no symptoms. For example, colonoscopy (KO-lun-AH-skuh-pee) and sigmoidoscopy (SIG-moid-AH-skuh-pee) are used to screen for colon and rectal cancer. These procedures can also help prevent cancer because they let doctors find and remove polyps (growths) that might become cancer if left alone.

To find cancer early

Endoscopy can sometimes be used to find cancer early, before it has had a chance to grow or spread.

Looking for causes of symptoms

When people go to the doctor with certain symptoms, endoscopy can sometimes be used to help find a cause. For instance:

  • Laryngoscopy to look at the vocal cords in people with long-term hoarseness
  • Upper endoscopy in people having trouble swallowing
  • Colonoscopy in people with anemia (low red blood cell counts) with an unknown cause
  • Colonoscopy in people with blood in their stool

Looking at problems found on imaging tests

Imaging tests such as x-rays and CT scans can sometimes show physical changes within the body. But these tests may only give information about the size, shape, and location of the problem. Doctors use endoscopes to see more details, like color and surface texture, when trying to find out what’s going on. Newer methods of endoscopy that include high magnification are being tested to find out whether they are more useful in detecting cancer and other abnormal cells on the inner surfaces of the body.

To diagnose and find out the stage (extent) of cancer

To get a tissue sample

Going one step further, most types of endoscopes have tools on the end that the doctor can use to take out small tissue samples. This procedure is called a biopsy (BY-op-see). Samples can be taken from suspicious areas and then looked at under a microscope or tested in other ways to see if cancer is there. A biopsy is usually the best way to find out if a growth or change is cancer or something else.

Getting a closer look

In some cases endoscopes are used to help find out how far a cancer has spread. Thoracoscopy (THOR-uh-KAHS -kuh-pee) and laparoscopy (LAP-uh-RAHS-kuh-pee) can be very useful in finding out if cancer has spread into the thorax (chest) or abdomen (belly). The surgeon can look into these places making only a small incision (cut) in the skin.

To get better pictures

Endoscopes can get pictures of the body parts they can get to. But some types of endoscopy can also be used to help get better, more detailed ultrasounds and x-rays in areas the scopes can’t quite reach. This can be especially useful when trying to find how much cancer is in the body (in other words, staging the cancer).

Endoscopic ultrasound (en-duh-SKAH-pick UL-truh-sound) (EUS): Ultrasound is an imaging test in which a wand-like instrument (called a transducer) is moved over the skin. The transducer sends sound waves into the body. The waves bounce back in a pattern a computer uses to make a picture. Endoscopic ultrasound (EUS) is a procedure in which a small transducer on the tip of an endoscope is put in through either the mouth or rectum. By putting the transducer on the tip of the endoscope, it can get closer to an organ or tumor to take more detailed ultrasound pictures.

EUS is used to get information about problems in the digestive tract and nearby organs. It can be used to see how deep a tumor might have grown into the rectum or esophagus, or into a nearby organ like the pancreas. It can also help show if lymph nodes are swollen, which could mean they have cancer in them. EUS is proving useful in staging some lung, digestive tract (esophagus, stomach, pancreas, etc.), and other cancers. EUS can also help a doctor guide a needle to take a biopsy.

Endoscopic retrograde cholangiopancreatography (en-duh-SKAH-pick RE-tro-grade ko-LAN-jee-oh-PAN-kree-uh-TOG-ruf-ee) (ERCP): ERCP is a complex procedure that helps doctors diagnose problems in the ducts of the pancreas, gall bladder, or liver. In this procedure, an endoscope is passed down the throat, through the stomach, and into the first part of the small intestine. The doctor then guides a tiny tube at the end of the endoscope into the common bile duct, which connects the intestine with the pancreas. A small amount of contrast material (dye) is pushed in, and x-rays are taken. The dye helps outline the bile ducts and pancreatic duct. The x-rays can show whether the ducts are narrowed or blocked, which could be caused by a gallstone or a cancer. The doctor doing this test can also put a small brush through the tube to take out some cells for biopsy.

To treat cancer

Destroying or removing cancer cells

Endoscopes can be used to take out or destroy small cancers. Small instruments passed through an endoscope can be used to cut out small growths. Doctors also can use tools like a cautery or laser through the tips of some endoscopes to burn or vaporize growths.

Surgery to take out cancer

Many types of endoscopic tools have been developed to let doctors perform minimally invasive surgery. This is sometimes called keyhole surgery. When it’s used for the abdomen (belly), it is called laparoscopic (LAP-uh-ruh-SKAH-pick) surgery. Instead of making one long surgical incision (cut), several small cuts are made in the skin, usually in the chest or abdomen. Long, thin instruments are then put through the cuts or holes to reach the inside of the body. A video endoscope – a thoracoscope (thuh-RAY-kuh-skop) or laparoscope – is put through one of the holes so that the surgeon can see inside during the operation.

This type of surgery is sometimes used to treat small lung cancers. This is called video-assisted thoracoscopic (THOR-uh-ko-SKAH-pick) surgery, or VATS. It can also be used for the colon (called laparoscopic colectomy, pronounced kuh-LEK-tuh-me), prostate (called laparoscopic radical prostatectomy), and some other organs, but not all doctors agree keyhole surgery is better than open surgery.

There are some benefits to keyhole surgery: Generally, less blood is lost during the operation and patients often recover faster and with less pain because the cuts are small. Some forms of keyhole surgery use robotic arms, which a surgeon controls from a console. This better magnifies the area so more precise work can be done with tiny, delicate surgical instruments.

Keyhole surgery also has some drawbacks: It usually means more time in the operating room and more drugs to keep the patient asleep (more time under anesthesia). It also takes away the surgeon’s ability to feel organs for problems that they may not be able to see.

Most studies have not found keyhole surgery to be any less effective than open surgery, at least in the short term. But as of yet there are no studies to show that the long-term outcomes are the same.

If you are thinking about some type of minimally invasive or keyhole surgery, it’s important to understand the known benefits and risks. It’s also important to find out what’s not yet known about the procedure. If you decide on keyhole surgery, be sure your doctor has a lot of experience with the procedure and is skilled with the technique.

To relieve symptoms of advanced cancer

Endoscopes can also be used for palliative (PAL-ee-uh-tiv) treatment (treatment given to reduce or control symptoms) in some cancers that can’t be cured by surgery. For example, instruments passed through endoscopes can be used to remove blockages in the lungs or digestive tract. If a tumor is narrowing an airway by pressing on its outside, endoscopy can be used to place a stent (a small, rigid tube) inside the airway to keep it open.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master's-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: February 3, 2015 Last Revised: February 23, 2015

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