Cancer of the Esophagus
Esophagus cancer is a terrible disease and it is becoming more and more common in this country. In fact, since 1970, the incidence of cancer of the esophagus has risen more rapidly than any other cancer in the United States - about a 700% rise in the last three decades. In the 1990's esophagus cancer has become the 8th most common cancer worldwide.
The reason for this sudden upsurge is not clear, but it is known that many of these cases are preceeded by damage and ulceration in the lower esophagus due to chronic acid reflux, or heartburn. Even though over 60 million Americans feel heartburn at least once a month, the problem is not really taken seriously. Of course, occasional mild heartburn is not serious. But many individuals live with severe heartburn on a daily basis and think that is just the way it is supposed to be. They go to the neighborhood drug store and purchase antacids in the giant economy size. They always have Tums or Rolaids in their pocket and often awaken during the night and take a dose of Maalox. Nowdays, they use Pepcid AC or Tagamet HB, or one of the many over-the-counter acid suppressors. They are not alone. In fact, Americans spend almost $15 billion a year on medications to treat heartburn. Still they have symptoms, but put off seeing their doctor. Not everyone with heartburn is at risk for cancer. But when it occurs, it is almost always fatal. Over 12,500 Americans a year get this form of cancer. The more severe the heartburn and more frequent the symptoms, the higher the risk of cancer. What is the cause and how can you prevent it?
First, some anatomy
The esophagus, or "foodpipe," is a hollow muscular tube about 12 inches long that carries food from your throat down into your stomach. The wall is made up of muscular tissue that contracts and helps propel the food downward. The inner lining, or mucosa, is covered and protected by squamous cells, much like those on your skin. The bottom of the esophagus connects to the stomach. Within this connection is a one-way "valve" called the lower esophageal sphincter, or LES. When you swallow, the LES opens briefly to allow movement of food into your stomach. It then closes tightly to prevent the backsplash, or reflux, of stomach acid up into the esophagus. The stomach has a special mucous layer to protect it from its own acid. The esophagus does not. It depends on the LES. If the LES malfunctions, and acid escapes from the stomach up into the esophagus, a burning sensation called heartburn occurs. If this is allowed to occur for long periods of time, the acid can destroy the normal squamous lining of the lower esophagus. Sometimes, when the damage heals, the lining is replaced by a different type of cell called glandular cells which are more like the cells that line the stomach. It's as if the stomach lining is "creeping up" into the lower esophagus. This condition is called Barrett's esophagus.
There are two types of cancer, or carcinoma, of the esophagus; one that forms from the normal squamous cells and one from these misplaced glandular cells (Barrett's). Since squamous cells line the entire esophagus, squamous cell cancer can form anywhere within the esophagus. The cancer that forms from Barrett's, called adenocarcinoma, and is usually found only in the lower third of the esophagus, where acid reflux is most likely to occur. At one time, squamous cell carcinoma was the cause of over 90% of cases of esophageal cancer. For unknown reasons, there has recently been a dramatic rise in cases of adenocarcinoma of the esophagus, which now accounts for over half of all cases. Adenocarcinomas are tumors that are derived from glandular structures. Such glandular structures are present within the inner linings, or mucosa, of the respiratory tract, gastrointestinal tract, genital tract, urinary tract and endocrine organs. They are classified according to the extent of gland formation as:
The well differentiated adenocarcinomas largely consist of glands and have the best prognosis for treatment, whereas in the poorly differentiatedtumors, glands are rarely formed. Poorly differentiated cancer do not respond well to treatment and have the worst prognosis.
- well differentiated adenocarcinomas
- moderately differentiated adenocarcinomas
- poorly differentiated adenocarcinomas
What are the symptoms of esophagus cancer?
Unfortunately, there are no "warning symptoms." Esophagus cancer is a lot like colon cancer; symptoms do not occur until the cancer has reached an advanced stage, when a cure is unlikely. The most common symptom of esophageal cancer is difficulty swallowing, also called dysphagia. At first, the episodes are mild and infrequent. The patient notes some resistance to swallowing, but the food eventually does makes its way into the stomach. The opening of the esophagus must narrow to about half of its normal diameter to cause this symptom. Therefore, dysphagia is commonly a late symptom. As the cancerous growth gradually enlarges and blocks the passageway, the symptoms become more frequent and more severe. To help pass the food through the esophagus, the body makes more saliva to lubricate the passageway. This causes some patients to bring up lots of thick mucus, or saliva. Some patients don't see the doctor until they can only swallow liquids or baby food. Others are forced to the emergency room with a piece of solid food such as meat firmly lodged in their esophagus. They are unable to even swallow their saliva and are seen in the waiting room with a spit cup. As the cancer advances, pain may be felt when swallowing or a dull pain may be felt behind the breastbone. About half of patients with esophageal cancer complain of unintentional weight loss, probably from decreased food intake.
How is esophagus cancer diagnosed?
If you have difficulty swallowing, it does NOT mean that you have cancer of the esophagus. In fact, most patients with this complaint have a hiatal hernia or non-cancerous stricture which blocks the passage of food. It is your doctor's job to determine the underlying cause of your symptoms. If you complain about difficulty swallowing, tests will be necessary to evaluate your condition. Testing will usually begin with a medical history and physical exam. The doctor will want to know how often and under what circumstances the problem occurs.
What are the stages of esophagus cancer?
- Most cases will require a "scope" test of the upper digestive system. Also known as a gastroscopy or EGD exam, this simple test is quickly and painlessly performed using a mild sedative. A thin flexible sterilized tube is passed through the mouth and down into the esophagus and stomach. A tiny color video camera within this instrument allows the doctor to directly examine the esophagus, stomach, and upper small intestine on a TV monitor. When necessary, photographs and biopsies can be obtained to determine if cancer is present, and if so, its type (squamous cell cancer or adenocarcinoma).
- One of the best ways to determine the nature of an esophageal tumor and its depth of invasion, is a special "scope" test known as an Endoscopic Ultrasound or EUS exam. This new procedure uses a modified endoscope which has a miniaturized ultrasound probe hidden in the tip. During an EUS exam, the doctor places the ultrasound probe directly into the esophagus, very close to the area of interest. It sends out very sensitive sound waves that penetrate deep into the tissues. Like sonar in a submarine, these sound waves bounce back forming a picture that shows how deeply the cancer has invaded into the esophagus. EUS has been shown to be superior to routine x-rays such as abdominal ultrasound, barium studies, CAT scans, and even MRI scans for looking at the local spread of cancer of the esophagus. This procedure is very highly specialized and is performed by a gastroenterologist who has extra training in this area.
- X-ray studies are often used. Barium x-rays may be requested to view the esophagus during the act of swallowing. A CT scan or MRI can help determine if the cancer has broken through the wall and spread beyond the esophagus.
- Less commonly, the doctor may request an esophageal manometry study which measures the strength and coordination of the esophageal contractions as well as the pressure of the special "trapdoor valve" between the stomach and esophagus.
The chance of recovery (prognosis) and choice of treatment depend upon the stage of the cancer (whether it is just in the esophagus or if it has spread to other places) and the patient's general state of health. For treatment purposes, there are five possible stages of esophagus cancer:
How is esophagus cancer treated?
- Stage 0 (carcinoma in situ)
This is a very early cancer. In fact, the cancer cells are found only in the top layer of the inner wall of the esophagus. The cancer has not invaded into the wall of the esophagus and has not spread to lymph nodes or other organs.
- Stage I
The cancer has invaded into the wall of the esophagus, but has not penetrated the thick muscular layer which surrounds it. It has not spread to nearby tissues, lymph nodes, or other organs.
- Stage II
There are two substages - IIA and IIB. In IIA, the cancer has penetrated the muscular layer and may have broken through the outer wall, but has not yet spread to nearby lymph nodes or any other organs. In IIB, the cancer may have spread to local lymph nodes, but has not spread to other tissues.
- Stage III
The cancer has spread to tissues or lymph nodes near the esophagus, but has not spread to other parts of the body.
- Stage IV
The cancer has entered the bloodstream and has spread to other parts of the body such as the liver or lung.
Treatment is individualized for each patient. Regardless of the stage, all patients can benefit from some form of treatment. Obviously, the more advanced the disease, the less likely a cure. Even then, treatment can provide relief of symptoms and slow the progression of the disease. Four kinds of treatment are commonly used. They may be used individually, or most commonly, in combination.
Surgery is the most common treatment for cancer of the esophagus, but less than 25% of patients are discovered early enough to offer a chance at curative surgery. Most often, it only helps symptoms and delays the progression somewhat. The esophagus is removed and the stomach is connected to the throat so that the patient can still swallow. Sometimes a part of the intestine is used to make the connection. The doctor may also remove lymph nodes around the esophagus and look at them under a microscope to see if they contain cancer.
- Surgery (taking out the cancer in an operation)
- Radiation therapy (using high-dose x-rays to kill cancer cells)
- Chemotherapy (using drugs to kill cancer cells)
- Endoscopic therapy to destroy some of the tumor with possible stent placement
Radiation therapy uses high energy x-rays to kill cancer cells and shrink tumors. Radiation can be given as an external beam that focuses radiation into the body. It can also be given internally by placing radioative material directly inside the esophagus near the cancer. Internal radiation is called brachytherapy. Radiation treatments are sometimes used before surgery to shrink the tumor before the operation. Radiation therapy can also be used when surgery can't be performed to slow down progression of the tumor and reduce symptoms. This is called palliative therapy.
Chemotherapy uses medications to kill cancer cells. Chemotherapy is called a systemic treatment because the drug is taken by mouth or vein, enters the bloodstream, and can kill cancer cells throughout the body. The problem with chemotherapy is that most drugs not only kill cancer cells, but also some normal cells in the process. This leads to side effects which can be serious, and at times, even life-threatening. The effects of chemotherapy alone are only temporary and cannot cure esophageal cancer, but recent studies suggest that chemotherapy given before surgery may improve overall survival, especially when combined with radiation therapy.
In the most advanced cases, gastroscopy, the scope test mentioned above, can be used to destroy part of the tumor and reopen the passageway. This does not remove the tumor, but does allow the patient to at least swallow a semisolid diet. As the tumor grows, the treatments have to be repeated. This can be done by laser therapy given through the scope to destroy some of the tumor bulk and open the passageway temporarily.
A relatively new technique called Photodynamic Therapy (PDT) is also helpful in some special cases. This procedure is performed by first giving an intravenous injection of a photosensitive chemical that selectively collects in the tumor over a period of several days. Using a gastroscope, a special type of laser light is focused on the cancer activating the concentrated chemical within the cancer cells. This light activation selectively kills the cancer cells and spares the adjacent normal esophagus lining. This procedure is best used to treat early superficial cancer since the wavelength of laser light cannot penetrate beyond the surface of the cancer and cannot treat cancer that has invaded deeper into the body. PDT is being studied as a way to eliminate glandular cells of Barrett's esophagus and early esophageal cancers. It can also help debulk large lesions and help temporarily open the passageway to reduce symptoms. One problem is that the chemical also causes skin sensitivity to sunlight, so patients must avoid direct sunlight for 6 weeks after treatment.
Sometimes a plastic covered metal wire stent is placed across the tumor to help keep the passageway open. This is only done in patients who are terminal since the stent can't be removed and does involve some risk. Eventually, it becomes a losing battle and the cancer wins. It is a depressing situation, but the procedure does help make the last few months more comfortable.
Each case is different, and it is important that patients with this cancer of the esophagus are treated by a team effort. This team is usually made up of their personal physician, a gastroenterologist, an experienced thoracic surgeon, a radiation specialist, and an oncologist (cancer specialist) to coordinate care and provide chemotherapy.
There are certain questions a patient should ask their oncologist once they get over the shock of learning that they have this type of cancer:
Chances of Survival
- What kind of cancer is it?
- What stage is the cancer in?
- What treatment choices are available?
- What is the expected benefit of each treatment?
- What are the risks and expected side effects of treatment?
- What is the chance for cure?
- If it cannot be cured, how can symptoms be reduced?
- How can my nutrition be maintained?
- Are there any research protocols that would be of benefit?
As in most cancers, the stage at the time of diagnosis helps plan treatment and gives some idea of the chance of survival. Every case is different and many factors are involved such as age and overall health status, but in general, the chance of surviving 5 years depends upon the stage at the time of diagnosis. Unfortunately, most cases are diagnosed in the more advanced stages, making a cure impossible.
How about screening?
||CHANCE OF SURVIVING 5 YEARS
||LESS THAN 5%
Unlike mamograms, pap smears, and PSA tests, there are no early detection tests in this country to screen the general population for esophageal cancer. Choices have to be made. Tragically, it is not financially feasible for the insurance industry to screen millions of adult Americans to detect the 12,500 cases of cancer of the esophagus that occur in this country each year. In Asia, where the incidence of this disease is much higher, mass screening programs are in place and often detect the disease in Stage O or Stage I. (In this country, less than 10% of cases are found in these early stages.) Here, screening efforts are directed primarily at high risk individuals such as those with chronic heartburn or known Barrett's esophagus.
Can esophagus cancer be prevented?
There is no way to definitely prevent esophagus cancer. Certain risk factors are involved. Men get this kind of cancer three times more often than women. Esophageal cancer is three times more common among African Americans than whites - mostly of the squamous cell type. You can't change your sex or race, but you can reduce your risk by avoiding the three main risk factors:
Those at highest risk are individuals who use tobacco in any form and drink regularly. Daily consumption of moderate to heavy alcohol increases the risk of esophageal cancer about 18 times above normal. Adding a pack or two of cigarettes a day, raise this risk to 44 times normal. These individuals can reduce their risk by stopping all tobacco, drinking in moderation, and aggressively evaluating and treating heartburn. Those that have heartburn more than twice a week or severe heartburn, should consult with their physician. Any one who has noted difficulty swallowing should be referred for a full evaluation.
- alcohol excess
Heartburn and Barrett's esophagus
If you stop and think about it, it's amazing that your stomach does not digest itself. The powerful hydrochloric acid inside your stomach is strong enough to liquify a piece of meat that you swallow. Your stomach is also made out of meat, or muscle tissue. Why doesn't it digest itself? Actually, the stomach is protected from its own acid by a special mucous layer that covers the inner lining. Unfortunately, the esophagus didn't get such a "raincoat." Instead, there is a one-way "valve" called the Lower Esophageal Sphincter. This is like a tiny trapdoor between your foodpipe and stomach. It lets the food go down into the stomach pouch, but then closes to prevent the backsplash of acid onto the delicate esophageal lining.
When the valve malfunctions, acid splashes (refluxes) upward and begins to damage the lower part of the esophagus. With repeated exposure, ulcers may form. This is called Gastroesophageal Reflux Disease, or GERD.
The tissue that lines the esophagus is different than that covering the stomach. When the esophagus ulcers heal, you would expect the normal esophagus tissue to patch the spot. Sometimes, for reasons unknown, the stomach lining creeps upward into the lower esophagus and covers the spot. Now you have stomach lining inside the lower esophagus. This condition, called Barrett's esophagus, is permanent even after the ulcers heal. It is not really a problem, except that the risk of cancer of the esophagus is higher is patients with Barrett's esophagus - 30 to 60 times greater than the general population.
While esophagus cancer can sometimes develop directly, Barrett's esophagus usually develops into cancer via a five-step process that permits time for early diagnosis and intervention. Over time, patients go through these stages:
Patients with GERD and those who have gone on to develop Barrett's changes need aggressive therapy and close monitoring to reduce their risk of cancer. The best approach is to prevent Barrett's in the first place by treating chronic heartburn avoiding all tobacco, and only drinking in moderation.
- esophagitis (GERD)
- Barrett's esophagus
- low-grade dysplasia (pre-cancer)
- high-grade dysplasia (almost cancer)
- carcinoma-in-situ Stage 0 ( a few early confined cancer cells)
- adenocarcinoma (cancer Stages I to IV)
Not everybody who experience heartburn needs to see their doctor. But if the symptoms are frequent, severe, or progressive, seek medical attention. While new and improved over-the-counter drugs like Pepcid AC and Tagamet HB have helped some heartburn sufferers find relief, many experts fear that the medications may be masking symptoms of more serious problems. While the drugs can be helpful for people with occasional heartburn and indigestion, a person should seek a doctor's help if symptoms last two weeks or more, experts say. If you have heartburn, ask yourself these questions:
- Do you take antacids two or more times a week?
- Do you take heartburn medicine(s) other than antacids?
- Does your heartburn interfere with your daily activities?
- Do these symptoms often occur after meals?
- Do these symptoms interfere with your sleep?
- Do you find that your medicine only relieves your symptoms for short periods of time?
- Do you have difficulty swallowing?
After treatments are completed, patients need to remain under surveillance for the possibility that the cancer may come back. This is termed "reoccurrence." Follow-up should be scheduled on a regular basis. The frequency of follow-up will depend on the condition of the patient and his/her disease. In each follow-up visit, patients are examined and a chest x-ray is normally obtained every few months. A CT scan of the chest, bone scan and endoscopy may be repeated periodically.