Understanding Types of Stomach Cancer
Stomach cancer (also called gastric cancer) causes the cells in the lining of the stomach to grow out of control. While the stomach is one part of the digestive system, stomach cancer shouldn’t be confused with cancer of the esophagus or intestines. Each of these areas are a separate part of the digestive system and will have their own symptoms and treatment approaches.
Stomach cancer tends to affect older adults—about 60% of the cases diagnosed each year are in men and women over the age of 65. Until the 1930’s, stomach cancer was a leading cause of death in the United States but today it falls much further down the list. Stomach cancer rates in the U.S. are much lower than other parts of the world but researchers aren’t sure exactly why.
Types of Stomach Cancer
There are four types of stomach cancer: adenocarcinomas, lymphomas, gastrointestinal stromal tumors (GIST), and carcinoid tumors. Adenocarcinomas make up most stomach cancer cases. The remaining types of stomach cancers are quite rare. Lymphomas only account for only account for about 4% of all stomach cancers. GIST cases develop throughout the digestive track but only 60-70% of these cases occur in the stomach. Carcinoid tumors start in hormone producing stomach cells and typically only make up 3% of stomach cancers.
Adenocarcinomas start in the innermost lining of the stomach tissue. Along with some precursor conditions that factor into an increased risk for adenocarcinoma of the stomach, there are also genetic and environmental factors that include:
- A family history of stomach cancer
- Having blood type A
- Hereditary nonpolyposis colon cancer syndrome
- Being of low socioeconomic status
- A diet low in fruits and vegetables
- Consumption of salted, smoked or poorly preserved foods
- Smoking cigarettes
Age is also a factor as gastric adenocarcinoma is rare for those under 40. Unfortunately, the early stages of adenocarcinoma create no specific symptoms so it can be very hard to identify until the disease has spread. 80% to 90% of patients with stomach cancer are diagnosed when their cancer is locally advanced. We call the spread of a cancer to surrounding tissues metastasis. The further a cancer metastasizes, the more difficult it is to treat.
Once an adenocarcinoma is identified, treatment will depend greatly on how far it has spread. If the cancer is still contained in the stomach, surgery may be able to remove it. If it has moved to other tissues outside the stomach, treatment will be more difficult and may require additional therapies with chemotherapy, radiation and surgical approaches.
Gastric lymphomas start in the lymphatic system’s lymph nodes—a network connected throughout your body designed to help protect you from infection and disease. The lymphatic system carries a specific type of white blood cell called a lymphocyte that is usually the source of lymphoma development when an error in production or a transformation in the cell triggers abnormal behavior that turns in to cancer.
As with adenocarcinoma, the early stages of this type of cancer may not produce any clear symptoms. According to researchers, nearly 50-60% of physical exams administered by a physician were normal. Additional testing including blood work, endoscopies and biopsies are necessary to make a full diagnosis.
Gastrointestinal Stromal Tumors (GIST)
According to The American Cancer Society, GIST causes are still unknown. While studies show some DNA mutation may be passed down genetically, the majority of cases are not inherited. Most cases are diagnosed in people over the age of 50 and are slightly more common in men.
Carcinoid tumors affect cells that make hormones. These tumors grow slowly and are often found at an early stage making them easier to treat. While causes are still unknown, there are factors that increase risk such as genetic diseases, race, gender, age and other conditions like pernicious anemia.
Identify your risk for stomach cancer through genetic testing
There’s no guaranteed way to prevent gastric cancer from developing, but you can know your risk. Because heredity plays a part, your body could hold clues to the likelihood of future illness in its genes. Genetic testing offered by companies like Pathway Genomics was once considered a privilege, but today anyone can undergo a simple test and learn more about their risk for developing a spectrum of conditions, including some types of gastric cancer. Genetic testing and cancer monitoring tools are more and more readily available. Learn more by talking to your doctor and take the first steps to a healthier future.