What Is Gastric (Stomach) Cancer?
Gastric cancer, also known as stomach cancer, develops when abnormal cells grow uncontrollably in the lining of the stomach. The stomach is a muscular organ located in the upper abdomen that helps digest food and move it into the intestines.
Most gastric cancers begin in the innermost lining of the stomach and are classified as adenocarcinomas. Less common types of stomach cancer include gastrointestinal stromal tumors (GISTs), lymphomas, and neuroendocrine tumors.
Gastric cancer often develops slowly over many years. Early-stage stomach cancer may not cause noticeable symptoms, making it difficult to detect. As the disease progresses, cancer cells can grow deeper into the stomach wall and spread to nearby lymph nodes or other organs.
Although rates of gastric cancer have declined in the United States over the past several decades, it remains a significant cause of cancer-related deaths worldwide. Advances in screening, molecular testing, targeted therapies, and immunotherapy are improving outcomes for many patients with gastric cancer.
Because every patient's cancer is unique, treatment recommendations are based on factors such as the cancer's location, stage, molecular characteristics, and the patient's overall health.
Risk Factors
Several factors may increase the risk of developing gastric cancer:
- Helicobacter pylori (H. pylori) Infection: Long-term infection with H. pylori bacteria is one of the strongest risk factors for gastric cancer.
- Age: Most cases of stomach cancer occur in people over age 60.
- Sex: Men are more likely than women to develop gastric cancer.
- Smoking: Tobacco use significantly increases the risk of stomach cancer.
- Diet: Diets high in smoked, salted, pickled, or processed foods and low in fruits and vegetables may increase risk.
- Obesity: Excess body weight has been linked to an increased risk of certain types of gastric cancer.
- Family History: Having a close relative with stomach cancer may increase a person's risk.
- Inherited Genetic Syndromes: Certain hereditary conditions, including Lynch syndrome, hereditary diffuse gastric cancer syndrome, and familial adenomatous polyposis (FAP), can increase risk.
- Chronic Stomach Conditions: Chronic gastritis, stomach polyps, pernicious anemia, and previous stomach surgery may increase the likelihood of developing gastric cancer.
- Occupational Exposures: Exposure to certain industrial chemicals, coal, rubber, or metal-processing environments may contribute to increased risk.
While these factors can increase the risk of gastric cancer, many people diagnosed with the disease have no known risk factors. Regular medical care and attention to persistent digestive symptoms may help support earlier diagnosis.