After a gastrointestinal carcinoid tumor has been diagnosed, tests are done to find out if cancer cells have spread within the stomach and intestines or to other parts of the body.
Staging is the process used to find out how far the cancer has spread. The information gathered from the staging process determines the stage of the disease. The results of tests and procedures used to diagnose gastrointestinal (GI) carcinoid tumors may also be used for staging. See the section for a description of these tests and procedures. A bone scan may be done to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner.
There are three ways that cancer spreads in the body.
Cancer can spread through tissue, the lymph system, and the blood:
- Tissue. The cancer spreads from where it began by growing into nearby areas.
- Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
- Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.
Cancer may spread from where it began to other parts of the body.
When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.
The metastatic tumor is the same type of tumor as the primary tumor. For example, if a gastrointestinal (GI) carcinoid tumor spreads to the liver, the tumor cells in the liver are actually GI carcinoid tumor cells. The disease is metastatic GI carcinoid tumor, not liver cancer.
- Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
- Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.
The plan for cancer treatment depends on where the carcinoid tumor is found and whether it can be removed by surgery.
For many cancers it is important to know the stage of the cancer in order to plan treatment. However, the treatment of gastrointestinal carcinoid tumors is not based on the stage of the cancer. Treatment depends mainly on whether the tumor can be removed by surgery and if the tumor has spread.
Treatment is based on whether the tumor:
- Can be completely removed by surgery.
- Has spread to other parts of the body.
- Has come back after treatment. The tumor may come back in the stomach or intestines or in other parts of the body.
- Has not gotten better with treatment.