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Stomach Cancer Stages
If you are diagnosed with stomach cancer (gastric cancer), doctors will do exams and tests to help determine if it has spread, and if so, how far. This process is called staging.
The stage describes the extent of the cancer in the body. It helps determine how serious the cancer is and how best to treat it.
Doctors also use a cancer's stage when talking about survival statistics.
What are the stages of small intestine cancer?
The earliest stage stomach cancers are called stage 0 (carcinoma in situ), and then range from stages I through IV.
As a rule, the lower the number, the less the cancer has spread. A higher number, such as stage IV, means cancer has spread more.
Although each person's cancer experience is unique, cancers with similar stages tend to have a similar outlook and are often treated in much the same way.
How is the stage determined?
The staging system most often used for stomach cancer is the American Joint Committee on Cancer (AJCC) TNM system.
This system is used to stage all stomach cancers (adenocarcinomas) except those starting in the gastroesophageal junction (where the stomach and the esophagus meet) or those that start in the cardia (the first part of the stomach) and are growing into the gastroesophageal junction. Those cancers are staged (and often treated) like cancers of the esophagus. Other types of cancer that can start in the stomach, such as gastrointestinal stromal tumors (GISTs), low-grade neuroendocrine tumors (NETs), and lymphomas, are staged differently as well.
The TNM system for stomach cancer is based on 3 key pieces of information:
The T category describes the extent of the main (primary) tumor, including how far it has grown into the layers of the stomach wall and if it has reached nearby structures or organs.
The 5 layers of the stomach wall include:
- Mucosa: The innermost layer, where nearly all stomach cancers start. The mucosa has 3 parts: epithelial cells, a layer of connective tissue (the lamina propria), and a thin layer of muscle (the muscularis mucosa).
- Submucosa: A supporting layer under the mucosa
- Muscularis propria: A thick layer of muscle that moves and mixes the stomach contents
- Subserosa
- Serosa: The outer, wrapping layer of the stomach
The N category describes any cancer spread to nearby lymph nodes.
The M category describes any spread (metastasis) to distant parts of the body, such as the liver or lungs.
Numbers or letters after T, N, and M provide more details about each of these factors. Higher numbers mean the cancer is more advanced.
Once a person’s T, N, and M categories have been determined, this information is combined in a process called stage grouping to assign an overall stage.
Clinical vs. pathologic stage
Stomach cancer might be staged at different times during the course of treatment.
Usually, cancer is first given a clinical stage. This is based on the results of any physical exams, biopsies, imaging tests, and procedures (such as upper endoscopy or laparoscopy) that have been done. (These exams and tests are described in Tests for Stomach Cancer.) The clinical stage can be used to help plan treatment.
If surgery is done to remove the cancer, the pathological stage (also called the surgical stage) can be determined. This is based on the results of any exams or tests that have been done, as well as the results from the surgery. Sometimes the pathological stage is different from the clinical stage. For example, surgery might show the cancer has spread farther than could be seen on imaging tests. The pathological stage can help determine if more treatment is needed and give a better idea about a person’s prognosis (outlook).
Some people might get other treatments before surgery, such as chemotherapy or radiation, to try to shrink the cancer and make the surgery easier. This is known as neoadjuvant treatment. Staging might be done again after this treatment to assess how well it worked.
AJCC stages of stomach cancer
The stages described below are based on the pathological stage of the cancer. If your cancer has been clinically staged or if you have had neoadjuvant therapy, it's best to talk to your doctor about your specific stage.
Stage grouping: Tis, N0, M0
There is high-grade dysplasia (very abnormal looking cells) in the stomach lining, OR there are cancer cells only in the top layer of cells of the mucosa (innermost layer of the stomach) that have not grown into deeper layers of tissue such as the lamina propria (Tis).
The cancer has not spread to nearby lymph nodes (N0) or distant parts of the body (M0).
This stage is also known as carcinoma in situ.
Stage IA
Stage grouping: T1, N0, M0
The main tumor has grown into the lamina propria, the muscularis mucosa, or submucosa (T1).
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0).
Stage IB
Stage grouping: Stage IB can have 2 possible stage groupings.
T1, N1, M0
The main tumor has grown into the lamina propria, the muscularis mucosa, or submucosa (T1), AND the cancer has spread to 1 to 2 nearby lymph nodes (N1).
The cancer has not spread to distant parts of the body (M0).
T2, N0, M0
The main tumor is growing into the muscularis propria layer (T2).
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0).
Stage IIA
Stage grouping: Stage IIA can have 3 possible stage groupings.
T1, N2, M0
The main tumor has grown into the lamina propria, the muscularis mucosa, or submucosa (T1), AND the cancer has spread to 3 to 6 nearby lymph nodes (N2).
The cancer has not spread to distant parts of the body (M0).
T2, N1, M0
The main tumor is growing into the muscularis propria layer (T2), AND the cancer has spread to 1 to 2 nearby lymph nodes (N1).
The cancer has not spread to distant parts of the body (M0).
T3, N0, M0
The main tumor is growing into the subserosa layer (T3).
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0).
Stage IIB
Stage grouping: Stage IIB can have 4 possible stage groupings.
T1, N3a, M0
The main tumor has grown into the lamina propria, the muscularis mucosa, or submucosa (T1), AND the cancer has spread to 7 to 15 nearby lymph nodes (N3a).
The cancer has not spread to distant parts of the body (M0).
T2, N2, M0
The main tumor is growing into the muscularis propria layer (T2), AND the cancer has spread to 3 to 6 nearby lymph nodes (N2).
The cancer has not spread to distant parts of the body (M0).
T3, N1, M0
The main tumor is growing into the subserosa layer (T3), AND the cancer has spread to 1 to 2 nearby lymph nodes (N1).
The cancer has not spread to distant parts of the body (M0).
T4a, N0, M0
The main tumor has grown through the stomach wall into the serosa, but it hasn’t grown into any of the nearby organs or structures (T4a).
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0).
Stage IIIA
Stage grouping: Stage IIIA can have 5 possible stage groupings.
T2, N3a, M0
The main tumor is growing into the muscularis propria layer (T2), AND the cancer has spread to 7 to 15 nearby lymph nodes (N3a).
The cancer has not spread to distant parts of the body (M0).
T3, N2, M0
The main tumor is growing into the subserosa layer (T3), AND the cancer has spread to 3 to 6 nearby lymph nodes (N2).
The cancer has not spread to distant parts of the body (M0).
T4a, N1, M0
The main tumor has grown through the stomach wall into the serosa, but it has not grown into any of the nearby organs or structures (T4a). The cancer has spread to 1 to 2 nearby lymph nodes (N1).
The cancer has not spread to distant parts of the body (M0).
T4a, N2, M0
The main tumor has grown through the stomach wall into the serosa, but it has not grown into any of the nearby organs or structures (T4a). The cancer has spread to 3 to 6 nearby lymph nodes (N2).
The cancer has not spread to distant parts of the body (M0).
T4b, N0, M0
The main tumor has grown through the stomach wall and into nearby organs or structures (T4b).
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0).
Stage IIIB
Stage grouping: Stage IIIB can have 6 possible stage groupings.
T1, N3b, M0
The main tumor has grown into the lamina propria, the muscularis mucosa, or submucosa (T1), AND the cancer has spread to 16 or more nearby lymph nodes (N3b).
The cancer has not spread to distant parts of the body (M0).
T2, N3b, M0
The main tumor is growing into the muscularis propria layer (T2), AND the cancer has spread to 16 or more nearby lymph nodes (N3b).
The cancer has not spread to distant parts of the body (M0).
T3, N3a, M0
The main tumor is growing into the subserosa layer (T3), AND the cancer has spread to 7 to 15 nearby lymph nodes (N3a).
The cancer has not spread to distant parts of the body (M0).
T4a, N3a, M0
The main tumor has grown through the stomach wall into the serosa, but it has not grown into any of the nearby organs or structures (T4a), AND the cancer has spread to 7 to 15 nearby lymph nodes (N3a).
The cancer has not spread to distant parts of the body (M0).
T4b, N1, M0
The main tumor has grown through the stomach wall and into nearby organs or structures (T4b). The cancer has spread to 1 to 2 nearby lymph nodes (N1).
The cancer has not spread to distant parts of the body (M0).
T4b, N2, M0
The main tumor has grown through the stomach wall and into nearby organs or structures (T4b). The cancer has spread to 3 to 6 nearby lymph nodes (N2).
The cancer has not spread to distant parts of the body (M0).
Stage IIIC
Stage grouping: Stage IIIC can have 4 possible stage groupings.
T3, N3b, M0
The main tumor is growing into the subserosa layer (T3), AND the cancer has spread to 16 or more nearby lymph nodes (N3b).
The cancer has not spread to distant parts of the body (M0).
T4a, N3b, M0
The main tumor has grown through the stomach wall into the serosa, but it has not grown into any of the nearby organs or structures (T4a), AND the cancer has spread to 16 or more nearby lymph nodes (N3b).
The cancer has not spread to distant parts of the body (M0).
T4b, N3a, M0
The main tumor has grown through the stomach wall and into nearby organs or structures (T4b), AND the cancer has spread to 7 to 15 nearby lymph nodes (N3a).
The cancer has not spread to distant parts of the body (M0).
T4b, N3b, M0
The main tumor has grown through the stomach wall and into nearby organs or structures (T4b), AND the cancer has spread to 16 or more nearby lymph nodes (N3b).
The cancer has not spread to distant parts of the body (M0).
Stage grouping: any T, any N, M1
The cancer might or might not have grown into any of the layers of the stomach wall (Any T), and it might or might not have spread to nearby lymph nodes (Any N).
The cancer has spread to distant lymph nodes or to organs such as the liver, lungs, brain, or the peritoneum (the lining of the space around the digestive organs) (M1).
Other staging categories you may see
- TX: Main tumor cannot be assessed due to lack of information.
- T0: No evidence of a main tumor.
- NX: Nearby lymph nodes cannot be assessed due to lack of information.
Resectable versus unresectable stomach cancer
The AJCC staging system provides a detailed summary of how far stomach cancer has spread. But for treatment purposes, doctors are often more concerned about whether the cancer can be removed (resected) completely with surgery.
- If it’s thought the cancer can be removed completely by surgery, it is considered potentially resectable.
- If the cancer is growing into vital structures or has spread too far to be removed completely, it is considered unresectable.
Many stomach cancers that haven’t spread to distant parts of the body are potentially resectable, even when they’ve spread to nearby lymph nodes, as long as the cancer hasn’t grown into important nearby structures such as major blood vessels.
Surgery to remove stomach cancer is a major operation, and unfortunately some people whose cancer is potentially resectable still might not be able to have the surgery if they aren’t healthy enough.
If you have stomach cancer that might be resectable, it’s important that a team of doctors from different specialties (for example, medical oncology, pathology, surgery, and radiation oncology) review and discuss the best options for treatment for you.
Even when surgery is planned, other treatments such as chemotherapy and/or immunotherapy are often given before and after surgery to help improve outcomes. This is known as perioperative therapy.
Cancers that have grown into nearby vital structures or that have spread to distant lymph nodes or to other organs are generally considered unresectable, so treatments other than surgery are usually the best option.
To learn more, see Treating Stomach Cancer.
- Written by
- References
Developed by the American Cancer Society medical and editorial content team with medical review and contribution by the American Society of Clinical Oncology (ASCO).
American Joint Committee on Cancer. Stomach Cancer. In: AJCC Cancer Staging Manual. 8th ed. New York, NY: Springer; 2017: 203–220.
Mansfield PF. Surgical management of invasive gastric cancer. UpToDate. 2025. Accessed at https://www.uptodate.com/contents/surgical-management-of-invasive-gastric-cancer on December 9, 2025.
National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Gastric Cancer. v.3.2025. Accessed at www.nccn.org on December 8, 2025.
Last Revised: February 27, 2026
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.
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