Published: 18 Jun 2025

ICD9: 151.1      ICD10: C16.9      ICD11: 2B72

Gastric cancer, commonly known as stomach cancer, is a type of cancer that begins in the cells of the stomach.
The stomach is a muscular sac located in the upper middle part of your abdomen, just below your ribs. It receives food from the esophagus and releases it into the small intestine.

Here's a breakdown of important aspects of stomach cancer:

Key Information:

Origin: Begins when healthy cells in the stomach develop changes (mutations) in their DNA. These mutations cause cells to grow and divide uncontrollably and to continue living when healthy cells would normally die. The accumulating abnormal cells can form a tumor.
Types: There are different types of stomach cancer, the most common being adenocarcinoma. Other, less common types include lymphoma, gastrointestinal stromal tumor (GIST), and carcinoid tumors. The type of cancer affects treatment options and prognosis.
Stages: Like other cancers, stomach cancer is staged based on its size, location, and whether it has spread to lymph nodes or other parts of the body. The stage influences treatment decisions and prognosis. Stages range from 0 (very early) to IV (advanced).

Causes & Risk Factors:

While the exact cause is often unknown, several factors can increase your risk:

_Helicobacter pylori (H. pylori)_ infection: A common bacterial infection of the stomach. Chronic infection can lead to inflammation and an increased risk of cancer.
Diet: A diet high in smoked, pickled, or salty foods, and low in fruits and vegetables, has been linked to higher risk.
Tobacco use: Smoking significantly increases the risk of stomach cancer.
Family history: Having a family history of stomach cancer increases your risk. Genetic factors can play a role.
Chronic gastritis: Long-term inflammation of the stomach lining.
Pernicious anemia: A condition in which the body can't absorb vitamin B12.
Stomach polyps: Certain types of stomach polyps can increase the risk.
Prior stomach surgery: Some types of stomach surgery can increase the risk years later.
Epstein-Barr virus (EBV) infection: In some cases, EBV has been linked to stomach cancer.
Age: The risk of stomach cancer increases with age.
Gender: Stomach cancer is more common in men than in women.
Blood type: People with blood type A may have a slightly higher risk.

Symptoms:

Early-stage stomach cancer often doesn't cause noticeable symptoms. As the cancer progresses, you may experience:

Persistent indigestion or heartburn
Loss of appetite
Unexplained weight loss
Abdominal pain or discomfort
Nausea and vomiting
Feeling full after eating only a small amount of food
Blood in your stool or black, tarry stools
Fatigue
Bloating after meals

Diagnosis:

Physical exam and medical history: The doctor will ask about your symptoms, risk factors, and medical history.
Upper endoscopy: A thin, flexible tube with a camera is inserted down your throat and into your stomach to visualize the lining. Biopsies can be taken during the procedure.
Biopsy: A tissue sample is taken from the stomach lining and examined under a microscope to look for cancer cells.
Imaging tests: CT scans, PET scans, and X-rays can help determine the extent of the cancer and whether it has spread.
Endoscopic ultrasound: An ultrasound probe is attached to an endoscope to get a better view of the stomach wall and surrounding tissues.
Blood tests: May be done to assess overall health and look for tumor markers.

Treatment:

Treatment options depend on the stage and location of the cancer, your overall health, and your preferences. Common treatments include:

Surgery: Often the primary treatment for stomach cancer, especially if the cancer is localized. Surgery may involve removing part or all of the stomach (gastrectomy), as well as nearby lymph nodes.
Chemotherapy: Uses drugs to kill cancer cells. It can be used before surgery (neoadjuvant), after surgery (adjuvant), or as the primary treatment for advanced cancer.
Radiation therapy: Uses high-energy rays to kill cancer cells. It may be used before or after surgery, or to relieve symptoms of advanced cancer.
Targeted therapy: Uses drugs that target specific vulnerabilities in cancer cells. These therapies are often used for advanced cancer.
Immunotherapy: Helps your immune system fight cancer. It's often used for advanced cancer.
Palliative care: Focuses on relieving symptoms and improving quality of life for people with advanced cancer.

Prevention:

While you can't completely prevent stomach cancer, you can reduce your risk by:

Treating _H. pylori_ infection: If you have _H. pylori_, get it treated with antibiotics.
Eating a healthy diet: Eat plenty of fruits, vegetables, and whole grains, and limit your intake of smoked, pickled, and salty foods.
Quitting smoking: Smoking significantly increases your risk.
Maintaining a healthy weight: Obesity is a risk factor.
Being aware of your family history: If you have a family history of stomach cancer, talk to your doctor about screening options.

Prognosis:

The prognosis for stomach cancer varies widely depending on the stage of the cancer at diagnosis, the type of cancer, your overall health, and how well you respond to treatment. Early detection and treatment are crucial for improving outcomes.

Important Considerations:

Early Detection: Because early-stage stomach cancer often has no symptoms, it's often diagnosed at a later stage. If you have risk factors or persistent symptoms, see your doctor.
Second Opinion: Consider getting a second opinion from a specialist in gastrointestinal cancers.
Clinical Trials: Clinical trials are research studies that test new treatments. Ask your doctor if a clinical trial is right for you.
Support Groups: Support groups can provide emotional support and practical advice for people with stomach cancer and their families.

This information is intended for general knowledge and informational purposes only, and does not constitute medical advice. It is essential to consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.