Barrett's esophagus (BE)
Def: Chronic peptic ulceration of the lower esophagus, which is lined by columnar epithelium, resembling the mucosa of the gastric cardia, acquired as a result of long-standing chronic esophagitis; esophageal stricture with reflux, and adenocarcinoma, also have been reported. Syn: Barrett esophagus, Barrett metaplasia.
The esophagus carries food and liquids from the mouth to the stomach. The stomach slowly pumps the food and liquids into the intestine, which then absorbs needed nutrients. This process is automatic and people are usually not aware of it. People sometimes feel their esophagus when they swallow something too large, try to eat too quickly, or drink very hot or cold liquids.
The muscular layers of the esophagus are normally pinched together at both the upper and lower ends by muscles called sphincters. When a person swallows, the sphincters relax to allow food or drink to pass from the mouth into the stomach. The muscles then close rapidly to prevent the food or drink from leaking out of the stomach back into the esophagus and mouth.
Barrett's esophagus (BE) is a serious condition in which changes occur in the cells that line the lower esophagus and cause the cells to become abnormal and precancerous. Barrett's esophagus is categorized as either long-segment or short-segment disease:
Long-segment BE occurs when abnormal cells affect 3 cm or more of the esophagus. This condition occurs in about 3 - 7% of GERD patients. It is associated with a more severe condition. Short-segment BE affects less than 3 cm of the esophagus and is found in about 10 - 17% of GERD patients.
About 10% of patients with symptomatic GERD have BE. In some cases, BE develops as an advanced stage of erosive esophagitis. Some studies suggest that individuals at highest risk for BE are obese white males over the age of 50 with persistent GERD who drink alcohol. However, a number of studies have reported no relationship between alcohol use or being male and overweight with BE. Such studies have also reported no higher risk in smokers or relatives of BE patients. Only the persistence of symptoms suggested a higher risk. Nevertheless, not all patients with BE have either esophagitis or symptoms of GERD.
The true prevalence of BE, in fact, is not entirely clear, since studies suggest that significantly more than half of people with BE have no GERD symptoms at all. BE, then, is likely to be much more prevalent and probably less harmful than is currently believed. (BE that occurs without symptoms can only be identified in clinical trials or in autopsies, so it is difficult to determine the true extent.) Some evidence suggests that the presence of specific immune factors may be involved in determining the development of BE.
Barrett's Esophagus and Cancer: The rate of esophageal cancer has been rising steadily at about 2% a year in white men. The American Cancer Society estimates that there will be 15,560 new cases of esophageal cancer and 13,940 deaths from the disease in 2007. Esophageal cancer is also very difficult to cure. The 5-year survival rate for all stages of esophageal cancer is 17% in white patients, and 12% in African-American patients. Most cases of esophageal cancer start with BE, with less than half of the cases developing with any symptoms. Of note, only a minority of BE patients develop cancer. Some evidence suggests that acid reflux may contribute to the development of cancer in BE. Researchers have speculated that exposure to extra acid in people with Barrett's esophagus produces more of an enzyme called NOX5-S, which may put stress on cells, leading to DNA damage.
Evidence suggests that asymptomatic BE is quite common in the general population, and if true, BE would pose far less of a threat than is now believed. (GERD itself poses no significant risk for esophageal cancer
. One study reported an annual incidence of 6.5 cancer cases per 10,000 people with regular GERD symptoms.)
Most of the future developments in the field of Barrett's esophagus will depend on the results of research studies.
Barrett's esophagus has no unique symptoms. Patients with Barrett's have the symptoms of GERD (for example, heartburn, regurgitation, nausea, etc.). The general trend is for Barrett's patients to have more severe GERD. However, not all Barrett's have marked symptoms of GERD, and some patients are detected accidentally with minimal or no symptoms of GERD.
Heartburn is a burning sensation behind the breastbone, usually in the lower half, but may extend all the way up to the throat. Sometimes, it is accompanied by burning or pain in the pit of the stomach just below where the breastbone ends. The second most common symptom is regurgitation (backup) of bitter tasting fluid. GERD symptoms often are worse after meals and when lying flat.
The refluxed, regurgitated fluid occasionally may enter the lungs or the voice box (larynx), resulting in what are called exatraesophageal (outside the esophagus) symptoms (manifestations) of GERD. These symptoms include:
New onset adult asthma.
Causes and Risk factors:
- Frequent bronchitis.
- Chronic cough.
- Sore throats.
Barrett's esophagus is caused by years of chronic heartburn (gastroesophageal reflux disease - GERD). When the esophagus (swallowing tube) is exposed to stomach acid and bile backwashing into it, these substances can cause injury to the normal squamous lining of the esophagus. Esophageal injury with inflammation is called esophagitis. In about 10% of those who have severe GERD, if acid injury to the esophagus continues over many years, the injured normal squamous lining of the esophagus does not grow back. Instead, it is replaced by a new abnormal lining called Barrett's esophagus (specialized intestinal metaplasia of the esophagus).
No one knows why Barrett's esophagus develops in response to acid injury to the esophagus. Barrett's esophagus produces mucous, like normal stomach lining, and therefore may resist acid injury better than the normal squamous lining of the esophagus. It may be the body's attempt to protect the esophagus against continued injury by chronic GERD. In fact, some people who have Barrett's esophagus report a past history of heartburn but none in recent years. This has led some researchers to believe that the development of Barrett's esophagus may relieve GERD (heartburn) symptoms in some people. No one knows why some people who have severe GERD develop Barrett's esophagus and why others do not.
There are no heartburn symptoms specific for or diagnostic of Barrett's esophagus. A procedure called esophagogastroduodenoscopy (EGD or upper endoscopy) with biopsy is the only way to know for sure whether you have Barrett's esophagus. If you have specialized intestinal metaplasia of the esophagus based on histologic analysis of an esophageal biopsy, you are at increased risk for the development of a type of esophageal cancer called esophageal adenocarcinoma. It is recommended that you undergo periodic endoscopic biopsy surveillance (cancer surveillance) to be able to detect a cancer when it is early and curable.
Unfortunately, most patients who have Barrett's esophagus never see a doctor for their heartburn symptoms. The vast majority of patients who develop an advanced (large) esophageal cancer are unaware that they have Barrett's esophagus.
Barrett's esophagus is commonly diagnosed because of another complication of heartburn (GERD), such as bleeding or dysphagia due to a stricture (food getting stuck in the esophagus due to esophageal narrowing). Sometimes doctors refer patients for upper endoscopy to check for Barrett's esophagus because the patient still has heartburn symptoms on medication. However, even if your heartburn symptoms go away on medication or without any treatment, you can have still Barrett's esophagus or esophageal adenocarcinoma.
As patients and physicians become more aware of Barrett's esophagus as a complication of GERD, more patients may seek medical attention for their heartburn and be referred by their physician for upper endoscopy to look for Barrett's esophagus. It has been recommended that patients who have a history of GERD for at least five years and are age 50 or older should undergo upper endoscopy to look for Barrett's esophagus. Barrett's esophagus should always be suspected in a Caucasian (white) man who has a longstanding problem with heartburn. However, anyone of any age, gender or race who has a chronic problem with heartburn could have Barrett's esophagus.
To date, no treatments can reverse the cellular damage done after Barrett's esophagus has developed, although some procedures are showing promise.
Medications: Some evidence suggests that a combination of proton-pump inhibitors to suppress acid, coupled with anti-inflammatory COX-2 inhibitors, might be a promising approach.
Proton-Pump Inhibitors: Some experts recommend very aggressive treatments to reduce acid reflux using high-dose proton-pump inhibitors. The standard agent has been omeprazole (Prilosec). Newer oral PPIs include lansoprazole (Prevacid), esomeprazole (Nexium), and rabeprazole (Aciphex). Even when drugs relieve symptoms completely, the condition usually recurs within months after the drugs are discontinued. In chronic cases, drugs may need to be taken throughout a patient's life. These agents provide no protection against Barrett's esophagus. Still, there is some evidence that acid reflux may contribute to the development of cancer in BE, although it is not yet known if acid blockers have any protective effects against cancer in these patients. COX-2 (cyclooxygenase-2) inhibitors reduce inflammation and pain, as do well-known agents such as aspirin and ibuprofen, but COX-2 inhibitors may pose less of a risk for peptic ulcers and bleeding. Some early evidence suggests they may be protective against cancerous changes in patients with Barrett's esophagus. However, Vioxx and Bextra have been withdrawn from the market due to their association with an increased risk of heart attack. Celebrex remains available, but must be used with caution, especially by patients with cardiovascular risk factors. Also, research is mixed on the benefits of NSAIDs for esophageal cancer. Some studies have found that they may decrease the risk of developing or dying from esophageal cancer. However, a 2007 study indicated that a small dose of Celebrex did not prevent the progression of cancer in Barrett's esophagus patients.
Procedures to Remove the Mucous Lining: Various techniques or devices have been developed to remove (ablate) the mucous lining of the esophagus. The intention is to remove early cancerous or precancerous tissue and allow regrowth of new and hopefully healthy tissue in the esophagus. Such techniques include photodynamic therapy (PDT) or laser, electrical, or heat probes.
Studies on the use of these ablation techniques combined with aggressive use of proton-pump inhibitors or surgical treatments are very encouraging. Some of these techniques may eventually even offer potential cures. At this time, they can be very effective in removing harmful tissue, although the benefits do not last in all patients. In one study, an average of 5.6 years after anti-GERD surgery and laser treatment, only a third of patients showed no evidence of renewed precancerous cell growth. These procedures also have complications, such as possible problems swallowing, that patients should discuss with their physician.
Esophagectomy: Esophagectomy is the surgical removal of all or part of the esophagus. Patients with Barrett's esophagus, who are otherwise healthy, are candidates for this procedure if endoscopy shows developing cancer. After esophageal removal, in total or in part, a new conduit for foods and fluids must be established to replace the absent esophagus. Alternatives include the stomach, colon, and part of the small intestine called the jejunum. The stomach is the optimal choice.
People with Barrett's esophagus have a low risk of developing a kind of cancer called esophageal adenocarcinoma. Less than 1 percent3 of people with Barrett's esophagus develop esophageal adenocarcinoma each year. Barrett's esophagus may be present for several years before cancer develops. Esophageal adenocarcinoma is frequently not detected until its later stages when treatments are not always effective.
Medicine and medications:
Treatment of Barrett esophagus should be the same as that of GERD. However, most authorities agree that it should be used with a proton pump inhibitor versus an H2-receptor antagonist due to the relative acid insensitivity of patients with Barrett esophagus.
H2-receptor antagonists: These agents are reversible competitive blockers of histamine at the H2 receptors, particularly those in the gastric parietal cells, where they inhibit acid secretion. The H2 antagonists are highly selective, do not affect the H1 receptors, and are not anticholinergic agents.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.
- Famotidine (Pepcid).
- Nizatidine (Axid).
- Proton pump inhibitors.
- Omeprazole (Prilosec).
- Lansoprazole (Prevacid).
- Esomeprazole (Nexium).
- Porfimaer (Photofrin).