How Long Does Stomach Cancer Take to Develop?

Stomach occurs when an abnormal mass of cells develops in the stomach. 

Most stomach cancer cases in the United States occur at the junction of your stomach and esophagus (gastroesophageal junction). In other countries where gastric cancer is more common, the cancer starts in the central portion of the stomach.

There are several types of stomach cancer. The most common type is adenocarcinoma, which accounts for 90%-95% of cases. Other types include neuroendocrine (carcinoid) tumors in the stomach, primary gastric lymphoma, and gastrointestinal stromal tumors.

Stomach cancer symptoms may be easily overlooked, especially in the early stages. For example, a stomachache may be misdiagnosed as indigestion or another stomach condition. 

Early symptoms of stomach cancer may include:

• Mild nausea
• Loss of appetite
• Fatigue
• Constant stomach pain or indigestion
• Heartburn
• Bloating, especially after eating

Symptoms of stomach cancer that can intensify as the disease progresses may include:

• Trouble swallowing
• Weakness
• Belching (burping)
• Ascites (fluid buildup around the stomach)
• Unexplained or unintentional weight loss
• Vomiting after meals
• Stomach pain, especially after meals
• Jaundice (the development of a yellow tint to the skin or the whites of the eyes)
• Blood tests that show anemia
• Persistent stomach ulcer

Cancer staging helps your doctor determine the best course of treatment based on the size and extent of the tumor. There are five stages of stomach cancer:

• Stage 0 (high grade dysplasia): Abnormal cells in the inner lining of the stomach are detected. Surgery may involve partially or completely removing the stomach, along with any adjacent lymph nodes.
• Stage I: Disease has not progressed past the thick muscle of the stomach wall. As with stage 0, surgery will probably be necessary to remove all or part of your stomach and any adjacent lymph nodes. You may undergo chemoradiation or chemotherapy, which can be used both before surgery to reduce the tumor and after surgery to eradicate any remaining cancer. Chemoradiation is the combination of chemotherapy and high-energy radiation therapy, which kills cancer cells.
• Stage II: The inner, supporting, or muscle layer of the stomach may have been affected by the cancer. Additionally, the cancer may have invaded neighboring lymph nodes.
• Stage III: Cancer may have spread to every layer of the stomach and nearby organs such as the colon or spleen. It may be smaller but reach deep into your lymph nodes.
• Stage IV: Cancer has spread to distant organs such as the liver, lungs, or brain. The cancer is much harder to cure at this stage.

Depending on the stage of stomach cancer, prognosis varies. People with stomach cancer who are diagnosed early typically have a considerably better prognosis than those who are diagnosed later. The 5-year survival rate may be as high as 70% (for early stage stomach cancer) or as low as 6% (for advanced stage stomach cancer).

For a more precise evaluation of your prognosis, talk to your doctor. Your prognosis is affected by factors such as the type of cancer you have, how far it has spread, your health, and how the cancer reacts to treatment.