Drugs that Reduce Stomach Acid Do Not Accelerate The Risk of Esophagus or Stomach Cancer
In the digestive system, an ulcer is an area where tissue has been destroyed by gastric juices and stomach acid. Peptic ulcer disease is a general term for ulcers that occur in the stomach or duodenum (upper part of the small intestine).
A peptic ulcer is an erosion or sore in the wall of the gastrointestinal tract.
The mucous membrane lining the digestive tract erodes and causes a gradual breakdown of tissue.
This breakdown causes a gnawing or burning pain in the upper middle part of the belly (abdomen).
Although most peptic ulcers are small, they can cause a considerable amount of discomfort.
Peptic ulcers occur when the acid and enzyme overcome the defense mechanisms of the gastrointestinal tract and cause an erosion in the mucosal wall.
An H2-receptor antagonist, often shortened to H2 antagonist, is a drug used to block the action of histamine on parietal cells in the stomach, decreasing acid production by these cells. These drugs are used in the treatment of dyspepsia, however their use has waned since the advent of the more effective proton pump inhibitors.
Overall, the use of drugs that reduce stomach acid, such as H2 blockers and proton pump inhibitors, do not increase the risk of cancer of the esophagus or stomach, according to a study reported in the journal Gut.
Common H2 blockers are ranitidine (Zantac) and cimetidine (Tagamet); and a common proton pump inhibitor is omeprazole (Prilosec).
"There have been concerns regarding the safety of long-time gastric acid suppression," senior investigator Dr. Mats Lindblad told Reuters Health. "I think our large study clearly suggests that long-time gastric acid suppression does not increase the risk" of cancer of the esophagus or stomach.
Lindblad and colleagues at the Karolinska Institute in Stockholm evaluated 7 years of patient data entered into the UK general practice database. The team identified 287 patients with esophageal cancer and 522 with stomach cancer. These subjects were compared with 10,000 randomly selected subjects without cancer.
The authors found some conditions for which acid-suppressing drugs are used, such as acid reflux disease, hiatal hernia and Barrett's esophagus, were associated with an increased risk of stomach and esophagus cancer. However, no apparent cancer risk was seen with other conditions, including peptic ulcer, gastritis, and indigestion. They found no evidence that the drugs themselves increased the risk.
These findings are in line with those of previous studies, continued Lindblad. The new information is that the cancer risk is probably due to underlying conditions, rather than an independent, harmful effect of these drugs.
In an interview with Reuters Health, Dr. Kenneth E.L. McColl, author of an accompanying editorial, agreed that the findings are consistent with such a conclusion.
However, McColl of the Western Infirmary, Glasgow, UK added that "a major weakness in the study is the relatively short duration of acid suppressive therapy examined. The development of cancer in humans is a slow process."
The period in question "is really too short to identify or exclude any direct effect between acid suppressive medication and" stomach or esophageal cancers.