Stages of Pancreatic Neuroendocrine Tumors

The plan for cancer treatment depends on where the NET is found in the pancreas and whether it has spread.

The process used to find out if cancer has spread within the pancreas or to other parts of the body is called staging. The results of the tests and procedures used to diagnose pancreatic neuroendocrine tumors (NETs) are also used to find out whether the cancer has spread. See the General Information section for a description of these tests and procedures.

Although there is a standard staging system for pancreatic NETs, it is not used to plan treatment. Treatment of pancreatic NETs is based on the following:

• Whether the cancer is found in one place in the pancreas.
• Whether the cancer is found in several places in the pancreas.
• Whether the cancer has spread to lymph nodes near the pancreas or to other parts of the body such as the liver, lung, peritoneum, or bone.

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.

• 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 metastatic tumor is the same type of tumor as the primary tumor. For example, if a pancreatic neuroendocrine tumor spreads to the liver, the tumor cells in the liver are actually neuroendocrine tumor cells. The disease is metastatic pancreatic neuroendocrine tumor, not liver cancer.

Pancreatic NETs can recur (come back) after they have been treated.

The tumors may come back in the pancreas or in other parts of the body.