What Causes Stomach Cancer vs. Stomach Ulcers?
Stomach Cancer Causes and Risk Factors
Stomach cancer remains the second most frequent cause of cancer-related death worldwide, with particularly high frequencies in Japan, China, Korea, parts of Eastern Europe, and Latin America. Established risk factors for stomach cancer include:
- Low socioeconomic status
- Male sex
- Cigarette smoking
- Advanced age
- A prior diagnosis of pernicious anemia (a chronic progressive disease caused by the failure of the body to absorb vitamin B-12)
- A diet deficient in fresh fruits and vegetables and rich in salted or smoked fish or meats and poorly preserved foods
- Treating benign stomach or duodenal ulcer disease by removing part of your stomach is associated with an increased risk of cancer developing in the remaining stomach, especially at least 15 years after the surgery.
- Recent studies have demonstrated a higher frequency of stomach cancer in people chronically infected with Helicobacter pylori, a common cause of chronic gastritis and peptic ulcer disease.
- A family history of stomach cancer is a further risk factor in the disease.
- People with blood type A also have an increased risk.
Stomach Ulcer Causes
When you eat, your stomach produces hydrochloric acid and an enzyme called pepsin to digest the food. The food is partially digested in the stomach and then moves on to the duodenum to continue the process. Peptic ulcers occur when the acid and enzyme overcome the defense mechanisms of the gastrointestinal tract and erode the mucosal wall. In the past it was thought that ulcers were caused by lifestyle factors such as eating habits, cigarette smoking, and stress. Now it is understood that people with ulcers have an imbalance between acid and pepsin coupled with the digestive tract's inability to protect itself from these harsh substances.
Research done in the 1980s showed that some ulcers are caused by infection with a bacterium named Helicobacter pylori, usually called H pylori. Not everyone who gets an ulcer is infected with H pylori. Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) can cause ulcers if taken regularly.
Some types of medical therapy can contribute to ulcer formation. The following factors can weaken the protective mucosal barrier of the stomach increasing the chances of getting an ulcer and slow the healing of existing ulcers.
- Aspirin, nonsteroidal anti-inflammatory drugs (such as ibuprofen and naproxen), and newer anti-inflammatory medications (such as celecoxib [Celebrex])
- Stress: physical (severe injuries or burns, major surgery)
- Cigarette smoking
- Radiation therapy:-used for diseases such as cancer
- People who take aspirin or other anti-inflammatory medications are at an increased risk even if they do not have H pylori infection.
- Elderly people with conditions such as arthritis are especially vulnerable.
- People who have had prior ulcers or intestinal bleeding are at a higher-than-normal risk.
If a person takes these medications regularly, alternatives should be discussed with a health-care professional. This is especially true if the affected individual has an upset stomach or heartburn after taking these medications.
Stomach Ulcers Spread by Feces
H pylori bacteria is spread through the stools (feces) of an infected person. The stool contaminates food or water (usually through poor personal hygiene).
The bacteria in the stool make their way into the digestive tracts of people who consume this food or water. This is called fecal-oral transmission and is a common way for infections to spread. The bacteria are found in the stomach, where they are able to penetrate and damage the lining of the stomach and duodenum. Many people who are exposed to the bacteria never develop ulcers. People who are newly infected usually develop symptoms within a few weeks.
Researchers are trying to discover what is different about the people who develop ulcers.
- Infection with H pylori occurs in all ages, races, and socioeconomic classes.
- It is more common in older adults, although it is thought that many people are infected in childhood and carry the bacteria throughout their lifetimes.
- It is also more common in lower socioeconomic classes because these households tend to have more people living together, sharing bathrooms and kitchen facilities.
- African Americans and Hispanic Americans are more likely to have the bacteria than Caucasians and Asian Americans.
It is important to distinguish between ulcers caused by H pylori and those caused by medications because the treatment is completely different.
Ulcers can be linked with other medical conditions.
People who worry excessively are usually thought to have a condition called generalized anxiety disorder. This disorder has been linked with peptic ulcers.
A rare condition called Zollinger-Ellison syndrome causes peptic ulcers as well as tumors in the pancreas and duodenum.