Stomach cancer often grows slowly for many years before causing symptoms. The majority of stomach cancers in the United States are diagnosed after they’ve spread beyond the stomach.

Stomach cancer makes up about 1.5% of cancers diagnosed in the United States. The lifetime risk of being diagnosed with stomach cancer is about 1 in 96 for men and 1 in 152 for women.

Stomach cancer usually isn’t detected until the cancer has grown large or spread to other tissues. Less than 30% of stomach cancers in the United States are diagnosed when the cancer is limited to the stomach.

Some subtypes of stomach cancer tend to grow slower than others. In this article, we look at the different types of stomach cancer and how fast they spread.

Is stomach cancer usually terminal?

People diagnosed with stomach cancer have a 5-year relative survival rate of about 33%. The 5-year relative survival rate refers to the odds of a person with the cancer being alive 5 years later compared to a person without the cancer.

Stomach cancer is often curable if it’s contained to your stomach when you’re diagnosed. However, more than 70% of people have cancer spread to other tissues when they’re diagnosed. Cancer that has spread to distant tissues isn’t usually considered curable.

Yearly stomach cancer deaths continue to drop in the United States, largely due to improvements in treatment. From 1975–2020, the number of deaths decreased by three times.

About 90–95% of stomach cancers are classified as adenocarcinoma. Adenocarcinoma starts in gland cells that line your stomach. It can be divided into two main types:

  • Intestinal adenocarcinoma: Intestinal adenocarcinoma tends to grow slower and is more likely to respond to targeted therapy drugs.
  • Diffuse adenocarcinoma: Diffuse adenocarcinoma grows throughout your stomach instead of in one location. It’s rarer and tends to be harder to treat.

Rarer types of stomach cancer include:

  • Gastric lymphoma: Gastric lymphoma starts in a type of white blood cell called lymphocytes. It makes up less than 5% of stomach cancers and tends to grow slowly. The 10-year survival rates have been reported to be over 90% for low-grade gastric lymphoma.
  • Gastrointestinal stromal tumors: Gastrointestinal (GI) stromal tumors develop in cells in the wall of the stomach called cells of Cajal. People with GI stromal tumors in any part of their GI tract have a 5-year, all stages combined, relative survival rate of about 85%.
  • Neuroendocrine stomach cancer: Neuroendocrine tumors start in cells that produce hormones in response to nerve signals. They tend to grow slowly. The 5-year relative survival rate for neuroendocrine cancers in all parts of the GI tract is about 94%.

How fast do stomach cancers grow?

Stomach cancer often grows silently for many years before symptoms become noticeable.

Studies have reported a doubling time for early-stage stomach cancer between 577 and 3,462 days, meaning that tumors double in size every 1.6–9.5 years. Studies have reported doubling times in advanced stomach cancer between 105 and 305 days, suggesting that advanced cancer may progress more rapidly.

Stomach cancer most commonly spreads to the liver. About 4–14% of people have spread to their liver when they’re diagnosed.

Stomach cancer is also known to spread to:

Stomach cancer often doesn’t cause symptoms in the early stages. When symptoms do appear, they often mimic those of other GI conditions. Symptoms are similar between males and females, but stomach cancer occurs more often in men.

Advanced stomach cancer may cause signs and symptoms such as:

Risk factors for stomach cancer

Risk factors for stomach cancer include:

  • male sex
  • increasing age
  • ethnicity, with non-Hispanic Caucasian people at a lower risk than other ethnic groups in the United States
  • Helicobacter pylori infection
  • being overweight
  • higher alcohol consumption, especially in people who consume more than 3 drinks per day.
  • tobacco use
  • previous stomach surgery
  • having a type of stomach polyp called an adenoma

Most stomach cancers are discovered after symptoms appear. For most people, this means that the cancer has grown large or spread beyond the stomach.

If your doctor suspects stomach cancer, they’ll likely order an upper endoscopy. This test involves inserting a thin tube with a camera down your throat and into your stomach. Your doctor can take a tissue sample called a biopsy with this tube to be tested in a laboratory for cancer.

Imaging tests can help determine the extent of the cancer or how well you’re responding to treatment. Imaging might include:

Stomach cancer remains the third highest cause of cancer-related death worldwide. The survival rate remains relatively low compared to other cancers since it often isn’t diagnosed until the cancer has grown large or spread.

Here’s a look at the 5-year relative survival rate of stomach cancer in the United States based on the National Cancer Institute’s SEER data from 2012–2018:

Stage5-year relative survival rates
localized72%
regional33%
distant6%
all stages33%

Stomach cancer usually grows for many years before it’s detected. In about 70% of people, it has spread beyond their stomach and about a third of people have had it spread to distant organs by the time they’re diagnosed.

The outlook for stomach cancer is poor once it spreads to distant locations. However, the number of stomach cancer deaths each year in the United States continues to decrease.