An antrectomy is the resection, or surgical removal, of a part of the stomach known as the antrum. The antrum is the lower third of the stomach that lies between the body of the stomach and the pyloric canal, which empties into the first part of the small intestine. It is also known as the antrum pyloricum or the gastric antrum. Because an antrectomy is the removal of a portion of the stomach, it is sometimes called a partial or subtotal gastrectomy.
Purpose
An antrectomy may be performed to treat several different disorders that affect the digestive system:
Peptic ulcer disease (PUD). An antrectomy may be done to treat complications from ulcers that have not responded to medical treatment. These complications include uncontrolled or recurrent bleeding and obstructions that prevent food from passing into the small intestine. Because the antrum produces gastrin, which is a hormone that stimulates the production of stomach acid, its removal lowers the level of acid secretions in the stomach.
Cancers of the digestive tract and nearby organs. An antrectomy may be performed not only to remove a malignant gastric ulcer, but also to relieve pressure on the lower end of the stomach caused by cancers of the pancreas, gallbladder, or liver.
Arteriovenous malformations (AVMs) of the stomach. AVMs are collections of small blood vessels that may develop in various parts of the digestive system. AVMs can cause bleeding into the gastrointestinal tract, resulting in hematemesis (vomiting blood) or melena (black or tarry stools containing blood). The type of AVM most likely to occur in the antrum is known as gastric antral vascular ectasia (GAVE) syndrome. The dilated blood vessels in GAVE produce reddish streaks on the wall of the antrum that look like the stripes on a watermelon.
Gastric outlet obstruction (GOO). GOO is not a single disease or disorder but a condition in which the stomach cannot empty because the pylorus is blocked. In about 37% of cases, the cause of the obstruction is be nign—most often PUD, gallstones, bezoars, or scarring caused by ingestion of hydrochloric acid or other caustic substance. The other 63% of cases are caused by pancreatic cancer, gastric cancer, or other malignancy that has spread to the digestive tract.
Penetrating gunshot or stab wounds that have caused severe damage to the duodenum and pancreas. An antrectomy may be done as an emergency measure when the blood vessels supplying the duodenum have been destroyed.
Demographics
Peptic ulcer disease (PUD) is fairly common in the general United States population. According to theCenters for Disease Control (CDC), about 10% of all Americans will develop an ulcer in the stomach or duodenum at some point in their life. About four million adults are diagnosed or treated each year for PUD; one million will be hospitalized for treatment; and 40,000 will have surgery for an ulcer-related condition. About 6,500 Americans die each year from complications related to PUD. The annual costs to the United States economy from peptic ulcer disease are estimated to be over $6 billion.
Peptic ulcers can develop at any age, but in the United States they are very unusual in children and uncommon in adolescents. Adults between the ages of 30 and 50 are most likely to develop duodenal ulcers, while gastric ulcers are most common in those over 60. Duodenal ulcers are more common in men, and gastric ulcers are more common in women. Other risk factors for PUD include heavy smoking and a family history of either duodenal or gastric ulcers.
GAVE, or watermelon stomach, is a very rare cause of gastrointestinal bleeding that was first identified in 1952. It has been associated with such disorders as scleroderma, cirrhosis of the liver, familial Mediterranean fever, and heart disease. GAVE affects women slightly more than twice as often as men. It is almost always found in the elderly; the average age at diagnosis is 73 in women and 68 in men.
Gastric cancer is the 14th most common type of malignant tumor in the United States; however, it occurs much more frequently in Japan and other parts of Asia than in western Europe and North America. About 24,000 people in the United States are diagnosed each year with gastric cancer. Risk factors for developing it include infection of the stomach lining by Helicobacter pylori; Asian American, Hispanic, or African American heritage; age 60 or older; heavy smoking; a history of pernicious anemia; and a diet heavy in dry salted foods. Men are more likely to develop gastric cancer than women. Some doctors think that exposure to certain toxic chemicals in the workplace is also a risk factor for gastric cancer.
Description
At present almost all antrectomies are performed as open procedures, which means that they are done through a large incision in the patient's abdomen with the patient under general anesthesia. After the patient is anesthetized, a urinary catheter is placed to monitor urinary output, and a nasogastric tube is inserted. After the patient's abdomen has been cleansed with an antiseptic, the surgeon makes a large incision from the patient's rib cage to the navel. After separating the overlying layers of tissue, the surgeon exposes the stomach. One clamp is placed at the lower end and another clamp somewhat higher, dividing off the lower third of the stomach. A cutting stapler may be used to remove the lower third (the antrum) and attach the upper portion of the stomach to the small intestine. After the stomach and intestine have been reattached, the area is rinsed with saline solution and the incision closed.
Most antrectomies are performed together with a vagotomy. This is a procedure in which the surgeon cuts various branches of the vagus nerve, which carries messages from the brain to the stomach to secrete more stomach acid. The surgeon may choose to perform a selective vagotomy in order to disable the branches of the nerve that govern gastric secretion without cutting the branches that control stomach emptying.
Some surgeons have performed antrectomies with a laparoscope, which is a less invasive type of surgery. However, as of 2003, this technique is still considered experimental.
Diagnosis
Diagnosis of PUD and other stomach disorders begins with taking the patient's history, including a family history. In many cases the patient's primary care physician will order tests in order to narrow the diagnosis. If the patient is older or has lost a large amount of weight recently, the doctor will consider the possibility of gastric cancer. If there is a history of duodenal or gastric ulcers in the patient's family, the doctor may ask questions about the type of discomfort the patient is experiencing. Pain associated with duodenal ulcers often occurs at night, is relieved at mealtimes, but reappears two to three hours after eating. Pain from gastric ulcers, on the other hand, may be made worse by eating and accompanied by nausea and vomiting. Vomiting that occurs repeatedly shortly after eating suggests a gastric obstruction.
The most common diagnostic tests for stomach disorders are:
Endoscopy. An endoscope is a thin flexible tube with a light source and video camera on one end that can be passed through the mouth and throat in order to look at the inside of the upper digestive tract. The video camera attached to the endoscope projects images on a computer screen that allow the doctor to see ulcers, tissue growths, and other possible problems. The endoscope can be used to collect tissue cells for a cytology analysis, or a small tissue sample for a biopsy. A tissue biopsy can be used to test for the presence of Helicobacter pylori, a spiral bacterium that was discovered in 1982 to be the underlying cause of most gastric ulcers, as well as to test for cancer. Endoscopy is one of the most effective tests for diagnosing AVMs.
Double-contrast barium x-ray study of the upper gastrointestinal tract. This test is sometimes called an upper GI series. The patient is given a liquid form of barium to take by mouth. The barium coats the tissues lining the esophagus, stomach, and small intestine, allowing them to be seen more clearly on an x ray. The radiologist can also watch the barium as it moves through the digestive system in order to pinpoint the location of blockages.
Urease breath test. This test can be used to monitor the effects of ulcer treatment as well as to diagnose the presence of H. pylori. The patient is given urea labeled with either carbon 13-C or 14-C. H. pylori produces urease, which will break down the urea in the test dose to ammonia and carbon dioxide containing the labeled carbon. The carbon dioxide containing the labeled carbon can then be detected in the patient's breath.
Preparation
Preparation for an antrectomy requires tests to evaluate the patient's overall health and fitness for surgery. These tests include an EKG, x rays, blood tests, and a urine test. The patient is asked to discontinue aspirin and other blood-thinning medications about a week before surgery. No solid food or liquid should be taken after midnight of the evening before surgery.
In most hospitals the patient will be given a sedative before the operation either intravenously or by injection. The general anesthesia is given in the operating room.
Aftercare
Aftercare in the hospital for an antrectomy is similar to the aftercare given for other operations involving the abdomen, in terms of incision care, pain medication, and antibiotics to minimize the risk of infection. Recuperation at home usually takes several weeks. The patient is given an endoscopic check-up about six to eight weeks after surgery.
The most important aspect of aftercare following an antrectomy is careful attention to diet and eating habits. About 30% of patients who have had an antrectomy or a full gastrectomy develop what is known as dumping syndrome. Dumping syndrome results from food leaving the stomach too quickly after a meal and being "dumped" into the small intestine. There are two types of dumping syndrome, early and late. Early dumping occurs 10–20 minutes after meals and is characterized by feelings of nausea, lightheadedness, sweating, heart palpitations, rapid heartbeat, and abdominal cramps. Late dumping occurs one to three hours after meals high in carbohydrates and is accompanied by feelings of weakness, hunger, and mental confusion. Most patients are able to manage dumping syndrome by eating six small meals per day rather than three larger ones; by choosing foods that are high in protein and low in carbohydrate; by chewing the food thoroughly; and by drinking fluids between rather than with meals.
Risks
In addition to early or late dumping syndrome, other risks associated with antrectomies include:
Diarrhea. This complication is more likely to occur in patients who had a vagotomy as well as an antrectomy.
Weight loss. About 30–60% of patients who have had a combined antrectomy/vagotomy lose weight after surgery. The most common cause of weight loss is reduced food intake due to the smaller size of the stomach. In some cases, however, the patient loses weight because the nutrients in the food are not being absorbed by the body.
Malabsorption/malnutrition. Iron-deficiency anemia, folate deficiency, and loss of calcium sometimes occur after an antrectomy because gastric acid is necessary for iron to be absorbed from food.
Dysphagia. Dysphagia, or discomfort in swallowing, may occur after an antrectomy when digestive juices from the duodenum flow upward into the esophagus and irritate its lining.
Recurrence of gastric ulcers.
Bezoar formation. Bezoars are collections of foreign material (usually vegetable fibers or hair) in the stomach that can block the passage of food into the small intestine. They may develop after an antrectomy if the patient is eating foods high in plant fiber or is not chewing them thoroughly.
Normal results
Normal results of an antrectomy depend on the reasons for the surgery. Antrectomies performed to reduce acid secretion in PUD or to remove premalignant tissue to prevent gastric cancer are over 95% successful. The success rate is even higher in treating watermelon stomach. Antrectomies performed to treat gastric cancer or penetrating abdominal trauma are less successful, but this result is related to the severity of the patient's illness or injury rather than the surgical procedure itself.
Morbidity and mortality rates
The mortality rate for antrectomies related to ulcer treatment is about 1–2%; for antrectomies related to gastric cancer, 1%–3%.
The rates of complications associated with antrectomies for ulcer treatment are:
Recurrence of ulcer: 0.5%–1%.
Dumping syndromes: 25%–30%.
Diarrhea: 10%.
Alternatives
As of 2003, antrectomy is no longer the first line of treatment for either peptic ulcer disease or GAVE. It is usually reserved for patients with recurrent bleeding or other conditions such as malignancy, perforation, or obstruction.
Although surgery, including antrectomy, is the most common treatment for stomach cancer, it is almost always necessary to combine it with chemotherapy, radiation treatment, or biological therapy (immunotherapy). The reason for a combination of treatments is that stomach cancer is rarely discovered early. Its first symptoms are often mild and easily mistaken for the symptoms of heartburn or a stomach virus. As a result, the cancer has often spread beyond the stomach by the time it is diagnosed.
Medication
Treatment of peptic ulcers caused by H. pylori has changed its focus in recent years from lowering the level of acidity in the stomach to eradicating the bacterium. Since no single antibiotic is effective in curing H. pyloriinfections, so-called triple therapy typically consists of a combination of one or two antibiotics to kill the bacterium plus a medication to lower acid production and a third medication (usually bismuth subsalicylate) to protect the stomach lining.
Specific types of medications that are used as part of triple therapy or for relief of discomfort include:
H2 blockers. These are used together with antibiotics in triple therapy to reduce stomach acid secretion. H2 blockers include cimetidine, ranitidine, famotidine, and nizatidine. Some are available as over-the-counter (OTC) medications.
Prostaglandins. These are given to treat ulcers produced by a group of pain medications known as NSAIDs. Prostaglandins protect the stomach lining as well as lower acid secretion. The best-known medication in this category is misoprostol.
Sucralfate. Sucralfate is a compound of sucrose and aluminum that covers ulcers with a protective coating that allows eroded tissues to heal.
Antacids. These compounds are available as OTC tablets or liquids.
Bismuth subsalicylate. Sold as an OTC under the trade name Pepto-Bismol, this medication has some antibacterial effectiveness against H. pylori as well as protecting the stomach lining.
Endoscopy
Endoscopy can be used for treatment as well as diagnosis. About 10 different methods are in use as of 2003 for treating bleeding ulcers and AVMs with the help of an endoscope; the most common involve the injection of epinephrine or a sclerosing solution; the application of a thermal probe to the bleeding area; or the use of a Nd:YAG laser to coagulate the open blood vessels. Watermelon stomach is now treated more often with argon plasma coagulation than with an antrectomy. Recurrent bleeding, however, occurs in 15–20% of ulcers treated with endoscopic methods.
Complementary and alternative (CAM) approaches
Complementary and alternative approaches that have been used to treat gastric ulcers related to PUD includeacupuncture, Ayurvedic medicine, and herbal preparations. Ayurvedic medicine, which is the traditional medical system of India, classifies people according to metabolic body type. People who belong to the type known as pitta are considered particularly prone to ulcers and treated with a diet that emphasizes "cooling" foods, including large quantities of vegetables. In Japanese medicine, ulcer remedies made from licorice or bupleurum are frequently prescribed. Western herbalists recommend preparations containing fennel, fenugreek, slippery elm, or marshmallow root in addition to licorice to relieve the pain of stomach ulcers.
"Arteriovenous Malformations." In The Merck Manual of Diagnosis and Therapy, edited by Mark H. Beers, MD, and Robert Berkow, MD. Whitehouse Station, NJ: Merck Research Laboratories, 1999.
Pelletier, Kenneth R., MD. The Best Alternative Medicine, Part II, "CAM Therapies for Specific Conditions: Ulcers." New York: Simon & Schuster, 2002.
"Peptic Ulcer Disease." In The Merck Manual of Diagnosis andTherapy, edited by Mark H. Beers, MD, and Robert Berkow, MD. Whitehouse Station, NJ: Merck Research Laboratories, 1999.
Thomson, A. B. R. and E. A. Shaffer. First Principles of Gastroenterology, 3rd ed. Oakville, ON: Canadian Association of Gastroenterology, 2002.
PERIODICALS
Appleyard, M. N. and C. P. Swain. "Endoscopic Difficulties in the Diagnosis of Upper Gastrointestinal Bleeding." World Journal of Gastroenterology 7 (2001): 308-12.
Busteed, S., C. Silke, C. Molloy, et al. "Gastric Antral Vascular Ectasia—A Cause of Refractory Anaemia in Systemic Sclerosis." Irish Medical Journal 94 (November-December 2001): 310.
Castellanos, Andres, MD, Barry D. Mann, MD, and James de Caestecker, DO. "Gastric Outlet Obstruction." eMedicine, February 12, 2002 [cited April 27, 2003]. <www.emedicine.com/med/topic2713.htm>.
De Caestecker, James, DO. "Upper Gastrointestinal Bleeding: Surgical Perspective." eMedicine, October 17, 2002 [cited April 27, 2003]. <www.emedicine.com/med/topic3566.htm>.
Fowler, Dennis, MD. "Laparoscopic Foregut Surgery: Less Commonly Performed Procedures." Minimal Access Surgery Center Newsletter, New York-Presbyterian Hospital 2 (Winter 2002): 7–10.
Komar, Aleksander R., MD and Prem Patel, MD. "Abdominal Trauma, Penetrating." eMedicine, April 25, 2002 [cited April 28, 2003]. <www.emedicine.com/med/topic2805.htm>.
Probst, A., R. Scheubel, and M. Wienbeck. "Treatment of Watermelon Stomach (GAVE Syndrome) by Means of Endoscopic Argon Plasma Coagulation (APC): Long-Term Outcome." Zeitschrift für Gastroenterologie 39 (June 2001): 447-52.
Stotzer, P. O., R. Willen, and A. F. Kilander. "Watermelon Stomach: Not Only an Antral Disease." Gastrointestinal Endoscopy 55 (June 2002): 897–900.
Tseng, Y. L., M. H. Wu, M. Y. Lin, and W. W. Lai. "Early Surgical Correction for Isolated Gastric Stricture Following Acid Corrosion Injury." Digestive Surgery 19 (2002): 276–80.
Yusoff, I., F. Brennan, D. Ormonde, and B. Laurence. "Argon Plasma Coagulation for Treatment of Watermelon Stomach." Endoscopy 34 (May 2002): 407–10.
Zarzaur, B. L., K. A. Kudsk, K. Carter, et al. "Stress Ulceration Requiring Definitive Surgery After Severe Trauma." American Surgeon 67 (September 2001): 875–79.
ORGANIZATIONS
American Gastroenterological Association (AGA). 4930 Del Ray Avenue, Bethesda, MD 20814. (301) 654-2055. <www.gastro.org>.
American Society for Gastrointestinal Endoscopy (ASGE). 1520 Kensington Road, Suite 202, Oak Brook, IL 60523 (630) 573-0600. <www.asge.org>.
Canadian Association of Gastroenterology (CAG). 2902 South Sheridan Way, Oakville, ON L6J 7L6 (888) 780-0007 or (905) 829-2504. <www.cag-acg.org>.
Centers for Disease Control and Prevention (CDC). 1600 Clifton Road, Atlanta, GA 30333. (888) MY-ULCER or (404) 639-3534. <www.cdc.gov>.
National Cancer Institute (NCI). NCI Public Inquiries Office, Suite 3036A, 6116 Executive Boulevard, MSC8332, Bethesda, MD 20892-8322. (800) 4-CANCER or (800) 332-8615 (TTY). <www.nci.nih.gov>.
WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?
An antrectomy is performed as an inpatient procedure in a hospital. It is usually performed by a specialist in gastrointestinal surgery or surgical oncology.
QUESTIONS TO ASK THE DOCTOR
What are the alternatives to an antrectomy for my condition? Which would you recommend and why?
How many antrectomies have you performed?
How likely am I to develop dumping syndrome if I have the procedure?
What is your opinion of laparoscopic antrectomies? Would I be eligible to participate in a clinical study of this procedure?
