How Is Cancer of the Esophagus Diagnosed?

How Is Cancer of the Esophagus Diagnosed?

Signs and symptoms of esophageal cancer

In most cases, cancers of the esophagus are discovered because of the symptoms they cause. Diagnosis in people without symptoms is rare and usually accidental (because of tests done to check other medical problems). Unfortunately, most esophageal cancers do not cause symptoms until they have reached an advanced stage, when a cure is less likely.

Dysphagia

The most common symptom of esophageal cancer is a problem swallowing, with the feeling like the food is stuck in the throat or chest. This is called dysphagia. This is often mild when it starts, and then gets worse over time. The opening of the esophagus is often narrowed to about half of its normal width. Dysphagia is commonly a late symptom caused by a large cancer.

When swallowing becomes difficult, people often change their diet and eating habits without realizing it. They take smaller bites and chew their food more carefully and slowly. As the cancer grows larger, the problem gets worse. People then may start eating softer foods that can pass through the esophagus more easily. They may avoid bread and meat, since these foods typically get stuck. The problem swallowing may even get bad enough that some people stop eating solid food completely and switch to a liquid diet. If the cancer keeps growing, at some point even liquids will not be able to pass. To help pass food through the esophagus, the body makes more saliva. This causes some people to complain of bringing up lots of thick mucus or saliva.

Pain

In some cases, people complain of pain or discomfort in the middle part of their chest. Some people describe a feeling of pressure or burning in the chest. These symptoms are more often caused by problems other than cancer, such as heartburn, and so they are rarely seen as a signal that cancer is present.

Pain with swallowing may occur when the cancer is large enough to block the esophagus. Pain may be felt a few seconds after swallowing, as food or liquid reaches the tumor and cannot pass it.

Weight loss

About half of patients with esophageal cancer lose weight (without trying to). This happens because their swallowing problems keep them from eating enough to maintain their weight. Other factors include decreased appetite and increase in metabolism from the cancer.

Other symptoms

Hoarseness, hiccups, pneumonia, and high blood calcium levels are usually signs of more advanced cancer of the esophagus. Sometimes the cancer will bleed. If there is enough blood, stools may turn black. This can also occur with other cancers and with some benign (noncancerous) diseases. It does not always mean that cancer is present.

If you have any of the following symptoms, please see a doctor right away for appropriate examination and diagnosis:

* dysphagia (a feeling of food getting stuck in your throat or chest)
* significant weight loss without dieting
* avoidance of solid food because of pain when you swallow
* hiccups and dysphagia together

History and physical exam

The doctor will take a complete history (medical interview) to check for risk factors and symptoms. The physical exam will provide information about signs of esophageal cancer and other health problems. If your doctor is concerned that you may have esophageal cancer, further tests will be needed to find out what is causing your problems.

Imaging studies

Barium swallow

In a barium swallow, a liquid called barium is swallowed. It coats the walls of the esophagus. When x-rays are taken, the barium outlines the esophagus clearly. This test can be done by itself, or as a part of a series of x-rays that includes the stomach and part of the intestine, called an upper gastrointestinal (GI) series. A barium swallow test can show any irregularities in the normally smooth surface of the esophageal wall.

A barium swallow test is often the first test done to see what is causing a problem with swallowing. Even small, early cancer can be seen using this test. Tumors grow out from the lining of the esophagus. These masses stick out into the lumen (the open area of the tube). They cause the barium to coat that area of the esophagus unevenly. In the barium x-ray, early cancers can look like small round bumps. They also can appear as a flat, raised area called a plaque. Advanced cancers look like large irregular areas and cause a narrowing of the width of the esophagus. A barium swallow test cannot be used to determine how far a cancer may have spread outside of the esophagus.

A barium swallow test can also be used to diagnose one of the more serious complications of esophageal cancer called a tracheoesophageal fistula. This occurs when the tumor destroys the tissue between the esophagus and the trachea (windpipe) and creates a hole connecting them. With this connection, anything that is swallowed can pass from the esophagus into the windpipe and lungs. This leads to frequent coughing and gagging. This problem can be helped with surgery or an endoscopy procedure.

Computed tomography (CT)

The CT scan is an x-ray procedure that produces detailed cross-sectional images of your body. Instead of taking one picture, like a conventional x-ray does, a CT scanner takes many pictures of the part of your body being studied as it rotates around you. A computer then combines these pictures into an image of a slice of your body.

CT scans are not usually used to make the initial diagnosis of esophageal cancer, but they can help see how far it has spread. CT scans often can show where the cancer is in the esophagus. These scans can also show the nearby organs and lymph nodes (bean-sized collections of immune cells that help fight infections and cancers), as well as distant areas of cancer spread. The CT scan can help to determine whether surgery is a good treatment option.

Before any pictures are taken, you may be asked to drink 1 to 2 pints of a liquid called oral contrast. This helps outline the esophagus and intestines so that certain areas are not mistaken for tumors. If you are having any trouble swallowing, you need to tell your doctor before the scan. You may also receive an IV (intravenous) line through which a different kind of contrast dye (IV contrast) is injected. This helps better outline structures in your body.

The injection can cause some flushing (redness and warm feeling that may last hours to days). A few people are allergic to the dye and get hives. Rarely, more serious reactions like trouble breathing and low blood pressure can occur. Medicine can be given to prevent and treat allergic reactions. Be sure to tell the doctor if you have ever had a reaction to any contrast material used for x-rays.

CT scans are more inconvenient than regular x-rays because they take longer and require you to lie still on a table while they are being done. Still, these scans are getting faster and the stay might be pleasantly short. Also, some people feel a bit confined by the ring they have to lie in when the pictures are being taken.

CT scans can also be used to guide a biopsy needle precisely into a suspected area of cancer spread. This procedure is called a CT-guided needle biopsy. The patient lies on the CT scanning table while a radiologist advances a biopsy needle toward the location of the mass. CT scans are repeated until the doctors can see that the needle is in the mass. A fine-needle biopsy sample (tiny fragment of tissue) or a core needle biopsy sample (a thin cylinder of tissue about one-half inch long and less than 1/8-inch in diameter) is removed and examined under a microscope.

Magnetic resonance imaging (MRI)

MRI scans use radio waves and strong magnets instead of x-rays. The energy from the radio waves is absorbed and then released in a pattern formed by the type of tissue and by certain diseases. A computer translates the pattern of radio waves given off by the tissues into a very detailed image of parts of the body. Not only does this produce cross-sectional slices of the body like a CT scanner, it can also produce slices that are parallel with the length of your body. A contrast material might be injected just as with CT scans but is used less often.

MRI scans are also very helpful in looking at the brain and spinal cord. They are not often needed to assess spread of esophageal cancer. MRI scans are a little more uncomfortable than CT scans. First, they take longer -- often up to an hour. Also, you have to be placed inside tube-like equipment, which is confining and makes many people uneasy. To stay calm, try keeping your eyes closed. Thinking of pleasant, relaxing mental images has also been shown to be helpful in making the time pass quickly. While you are in the MRI machine you will be able to talk to the technician during the whole procedure.

People with a fear of enclosed spaces (claustrophobia) have a very hard time getting an MRI. If you have a problem with tight spaces, talk to your doctor about it. Your doctor may give you a medicine for anxiety to take before the scan. If that is not enough, your doctor may be able to have the scan done using an open MRI. An open MRI does not have an enclosed tube. Although these scanners are less available than regular MRI machines, many cities have a center with an open MRI.

The MRI machine also makes a thumping noise like a washing machine that you may find annoying. Some places provide headphones with music to block this out. Most people have little difficulty with their MRI experience, but you should feel free to discuss any concerns you have with your health care team.

Positron emission tomography (PET)

In this test, radioactive glucose (sugar) is injected into the vein. Because cancers use sugar much faster than normal tissues, the radioactivity will tend to concentrate in the cancer. A scanner is used to spot the radioactive deposits. This test is useful for finding areas of cancer spread. It can help find small collections of cancer cells that may not be seen on other tests.

The uptake of the radioactive glucose ("brightness") may be measured. Studies are ongoing to see if the degree of uptake or "brightness" can be used as to tell how fast the tumor is growing. Studies are also looking to see if changes in the brightness on a PET scan can be used to see if treatment, such as chemotherapy, is working.

Endoscopy

Upper endoscopy

An endoscope is a flexible, very narrow tube with a video camera and light on the end. During an upper endoscopy procedure, the patient is sedated (made sleepy) to allow the endoscope to pass through the mouth and into the esophagus and stomach. The camera is connected to a television set, allowing the doctor to see abnormalities in the wall of the esophagus clearly.

Endoscopy is an important test for diagnosing esophageal cancer. The doctor can see the cancer through the scope and biopsy it. A tissue sample (biopsy) can be removed from any area that doesn't look normal (through the endoscope). These samples are sent to the laboratory so that a doctor can look at them under a microscope to see if cancer is present. If the esophageal cancer is blocking the opening (called the lumen) of the esophagus, then certain instruments can be used to help enlarge the opening to help food and liquid pass. Upper endoscopy can give the surgeon information for follow-up surgery, including the size and spread of the tumor and whether the tumor can be completely removed.

Endoscopic ultrasound

Ultrasound tests use sound waves to take pictures of parts of the body. For an endoscopic ultrasound, the probe that gives off the sound waves is at the end of an endoscope. This allows the probe to get very close to the cancer.

This test is very useful in finding the size of an esophageal cancer and how far it has grown into nearby tissues. The endoscope with the small ultrasound probe is placed into the esophagus. The probe sends out very sensitive sound waves that penetrate deep into tissues. The sound waves bounce off normal tissue and any cancer that is present. They are picked up by the probe and a computer turns the pattern of sound waves into a picture. The picture shows how deeply the tumor has invaded into the esophagus. This test uses no radiation and is very safe. It can detect small abnormal changes very well.

Endoscopic ultrasound can help determine how much of the tissue next to the esophagus (including nearby lymph nodes) is affected by the cancer. This helps surgeons decide which tumors can be surgically removed and which cannot.

Bronchoscopy

This procedure uses an endoscope to look into the trachea (windpipe) and bronchi (tubes leading from the trachea into the lung). This lets the doctor see if the cancer has grown into these structures. The patient is sedated for this procedure.

Thoracoscopy and laparoscopy

These procedures allow the doctor to see lymph nodes and other organs near the esophagus inside the chest (by thoracoscopy) or the abdomen (by laparoscopy) through a hollow lighted tube. The surgeon can operate instruments through the tube and remove lymph node samples and take biopsies to see if the cancer has spread. This information is often important in deciding whether or not a person is likely to benefit from surgery. These procedures are done in an operating room and under general anesthesia.

Biopsy

An area may look like cancer, but the only way to know for sure is to do a biopsy. For a biopsy, the doctor removes a small piece of tissue (usually from an area that looks abnormal). A doctor called a pathologist then looks at the tissue under the microscope to see if any cancer cells are present. If there is cancer, the pathologist will determine what type it is (adenocarcinoma or squamous cell). It takes at least a couple of days to get the results of a biopsy.