Stomach cancer, also known as gastric cancer, is a disease in which malignant (cancerous) cells form in the lining of the stomach. The stomach is a vital organ that aids in digestion and nutrient absorption. Stomach cancer typically develops over several years and is often diagnosed at an advanced stage due to its subtle early symptoms. The disease can originate in different parts of the stomach and spread to nearby organs or distant parts of the body through metastasis.
Stomach cancer begins when healthy cells in the stomach lining undergo genetic mutations that cause them to grow uncontrollably. These cells can form a tumor that disrupts normal digestive functions. Over time, cancer can invade deeper layers of the stomach and spread to lymph nodes, liver, pancreas, and other organs.
Aggressive and difficult to detect early – Many cases are diagnosed at advanced stages.
Multiple subtypes – Includes adenocarcinoma (most common), lymphoma, gastrointestinal stromal tumors (GISTs), and carcinoid tumors.
Strong link to lifestyle and infection – Factors such as diet, Helicobacter pylori (H. pylori) infection, and smoking play a role.
Treatment varies by stage – Surgery, chemotherapy, radiation, targeted therapy, and immunotherapy are commonly used.
The exact cause of stomach cancer is not fully understood, but several factors can increase the risk:
H. pylori infection – A bacterial infection known to cause stomach ulcers and chronic inflammation.
Dietary factors – High consumption of salted, smoked, and pickled foods increases risk.
Tobacco and alcohol use – Both contribute to stomach lining irritation and cancer risk.
Family history – A genetic predisposition to stomach cancer may be inherited.
Previous stomach surgery – Surgeries such as gastric bypass can alter stomach acid production, leading to increased risk.
Pernicious anemia – A condition that affects vitamin B12 absorption and increases stomach cancer risk.
Obesity – Associated with chronic inflammation and increased cancer risk.
Early-stage stomach cancer often presents with mild or nonspecific symptoms, leading to delayed diagnosis. Common symptoms include:
Persistent indigestion or heartburn
Unexplained weight loss
Loss of appetite or feeling full quickly
Nausea and vomiting (sometimes with blood)
Abdominal pain or bloating
Blood in the stool (dark, tarry stools)
Fatigue and weakness due to anemia
Stomach cancer is categorized into different types based on the cell origin:
Originates in the glandular cells of the stomach lining.
Accounts for over 90% of stomach cancer cases.
Can be classified as intestinal or diffuse type based on cellular characteristics.
Rare tumors that develop in the stomach’s connective tissue.
May be benign or malignant.
Typically associated with mutations in the KIT gene.
A cancer of the immune system affecting the stomach’s lymphatic tissue.
Common in individuals with weakened immune systems or chronic H. pylori infections.
Develop from hormone-producing cells in the stomach.
Usually grow slowly but can produce excessive hormones affecting bodily functions.
To confirm a stomach cancer diagnosis, doctors use several diagnostic tests:
Endoscopy (EGD) – A flexible tube with a camera is inserted through the throat to examine the stomach lining.
Biopsy – A tissue sample is collected during an endoscopy and examined for cancerous cells.
Imaging tests
CT scan – Determines the extent of cancer spread.
PET scan – Helps detect metastasis.
Upper GI X-ray with barium – Highlights abnormalities in the stomach.
Blood tests
Tumor markers such as CA 19-9 and CEA may be elevated.
Tests for anemia and infection with H. pylori.
Treatment depends on the cancer stage, type, and patient’s overall health. Common treatment approaches include:
Subtotal gastrectomy – Partial removal of the stomach.
Total gastrectomy – Complete removal of the stomach, followed by reconstruction of the digestive tract.
Lymph node dissection – To prevent cancer spread.
Used before surgery (neoadjuvant) to shrink tumors or after surgery (adjuvant) to kill remaining cancer cells.
Common drugs: 5-FU, cisplatin, oxaliplatin, and capecitabine.
Uses high-energy rays to target cancer cells.
Often combined with chemotherapy.
Attacks specific proteins or genes in cancer cells.
HER2-positive stomach cancers may be treated with trastuzumab (Herceptin).
Boosts the immune system to recognize and attack cancer cells.
Drugs like pembrolizumab (Keytruda) may be used for advanced cases.
Focuses on improving quality of life for patients with advanced cancer.
Includes pain management, nutritional support, and psychological counseling.
The outlook for stomach cancer depends on early detection, treatment effectiveness, and overall health.
Localized cancer (early-stage) – 5-year survival rate of 70%.
Regional spread (nearby tissues/lymph nodes) – 5-year survival rate of 30-50%.
Distant metastasis (advanced stage) – 5-year survival rate below 10%.
Cancer stage at diagnosis – Earlier detection leads to better outcomes.
Treatment response – Some cancers are more responsive to therapies than others.
Overall health – Stronger immune function supports better recovery.
While stomach cancer cannot always be prevented, adopting a healthy lifestyle can lower risk:
Eat a diet rich in fruits, vegetables, and whole grains.
Avoid excessive salt, smoked foods, and processed meats.
Quit smoking and limit alcohol intake.
Maintain a healthy weight and exercise regularly.
Get screened if you have a family history or chronic stomach issues.
Living with stomach cancer can be challenging, but with the right support and lifestyle adjustments, patients can maintain a good quality of life.
Smaller, frequent meals – To aid digestion.
Soft and liquid foods – Easier to swallow and digest.
Nutritional supplements – Ensure adequate calorie and protein intake.
Avoid irritants – Limit spicy, acidic, and processed foods.
Counseling and support groups – Help cope with emotional challenges.
Mindfulness and stress management – Yoga and meditation can improve mental health.
Family and caregiver support – A strong support system enhances coping strategies.
Frequent monitoring to detect recurrence or complications.
Adherence to treatment plans improves prognosis.