After the healthcare team confirms a diagnosis of neuroendocrine tumor, the next step is to find the cancer's stage. The stage of a neuroendocrine tumor tells the healthcare team about the size of the cancer. It also tells the care team whether the cancer has spread to nearby lymph nodes or to other parts of the body.
The cancer's stage gives healthcare teams a shared way of describing the cancer. The care team uses the stage to help choose the treatment plan. It also gives the care team a general understanding of the prognosis of the cancer.
Staging tests
To find the stage, the healthcare team uses the results of tests and procedures, including:
- Imaging tests. Imaging tests may include CT, MRI and PET scans. These tests can show the size of the cancer and whether it has spread in the body. Healthcare teams use this information to decide on the stage.
- Biopsy. A biopsy collects a sample of tissue for testing in a lab. Tests can show whether the cancer cells are well differentiated or poorly differentiated. This helps the healthcare team decide what set of stages to use for the cancer.
Healthcare professionals use specific stages for some well-differentiated neuroendocrine tumors. These tumors tend to grow slowly and act in a unique way, so they are staged separately from other cancers.
Poorly differentiated neuroendocrine tumors don't have specific stages. Instead, these cancers are staged using the stages for the organ in which they start. For example, poorly differentiated pancreatic neuroendocrine tumors tend to grow quickly. They act like other kinds of pancreatic cancer, so the staging follows the stages for pancreatic cancer.
The stages of neuroendocrine tumors aren't affected by whether the cancer is functional or nonfunctional. A functional neuroendocrine tumor makes hormones that cause symptoms. A nonfunctional neuroendocrine tumor doesn't make hormones or doesn't make enough to cause symptoms.
The stages also aren't affected by cancer grade. The grade tells the healthcare team how quickly the cancer is growing.
Pancreas neuroendocrine tumors
The stages for pancreatic neuroendocrine tumors only apply to well-differentiated cancers. Poorly differentiated pancreatic neuroendocrine tumors use the same stages that are used for pancreatic cancer in general.
The stages of well-differentiated pancreatic neuroendocrine tumors range from 1 to 4. A lower stage means the cancer is smaller and only in the pancreas. As the cancer grows or spreads, the stages get higher.
- Stage 1. A stage 1 pancreatic neuroendocrine tumor is small and only in the pancreas. The cancer is less than 2 centimeters (about 3/4 inch) at its widest point.
- Stage 2. A stage 2 cancer may still only be in the pancreas, but it is larger than stage 1. At this stage, the cancer may have grown to invade structures near the pancreas, such as the small intestine or the bile duct.
- Stage 3. A stage 3 cancer may be a large cancer that has grown to invade other structures near the pancreas. It might grow beyond the pancreas and into the stomach, spleen, colon or major blood vessels. A stage 3 cancer also can be any size cancer that spreads to the nearby lymph nodes.
- Stage 4. A stage 4 pancreatic neuroendocrine tumor is any cancer that spreads to other parts of the body. This cancer most often spreads to the liver. It also can spread to the lungs, bones, peritoneum and distant lymph nodes.
Colon and rectum neuroendocrine tumors
The stages for neuroendocrine tumors of the colon and rectum only apply to well-differentiated cancers. Poorly differentiated colon and rectum neuroendocrine tumors use the same stages that are used for colon cancer and rectal cancer in general.
The stages of well-differentiated colon and rectal neuroendocrine tumors range from 1 to 4. A lower stage means the cancer is small and limited to the inner layers of the colon or rectum. As the cancer grows or spreads, the stages get higher.
- Stage 1. A stage 1 neuroendocrine tumor in the colon or rectum is small and only affects the innermost layers of the colon or rectum. The cancer is less than 2 centimeters (about 3/4 inch) at its widest point.
- Stage 2. A stage 2 cancer may be larger than 2 centimeters. It also may be a cancer that extends deeper into the wall of the colon or rectum.
- Stage 3. A stage 3 cancer may be large and may have grown through the wall of the colon or rectum. This stage also includes any cancer that has spread to nearby lymph nodes.
- Stage 4. A stage 4 neuroendocrine tumor in the colon or rectum has spread to other parts of the body. This cancer most often spreads to the liver, peritoneum and distant lymph nodes. It also can spread to the bones, lungs and other parts of the body.
Small intestine neuroendocrine tumors
The stages for neuroendocrine tumors of the small intestine only apply to well-differentiated cancers. Poorly differentiated small intestine neuroendocrine tumors are staged using the stages for small intestine cancer in general.
The stages of well-differentiated small intestine neuroendocrine tumors range from 1 to 4. A lower stage means the cancer is small and limited to the intestine. As the cancer grows or spreads, the stages get higher.
- Stage 1. A stage 1 small intestine neuroendocrine tumor is small and only affects the inner layers of the intestine. The cancer is less than 1 centimeter (a little less than 1/2 inch) at its widest point.
- Stage 2. A stage 2 cancer may be larger than 1 centimeter or it may grow deeper into the wall of the intestine.
- Stage 3. A stage 3 cancer may have grown through the wall of the intestine. This stage also includes any cancer that has spread to nearby lymph nodes.
- Stage 4. A stage 4 small intestine neuroendocrine tumor has spread to other parts of the body. This cancer most often spreads to the liver and peritoneum. It also can spread to bones, lungs and distant lymph nodes.
Appendix neuroendocrine tumors
The stages for appendix neuroendocrine tumors only apply to well-differentiated cancers. Poorly differentiated neuroendocrine tumors of the appendix are staged differently, using the system for appendix cancer in general.
The stages of well-differentiated appendix neuroendocrine tumors range from 1 to 4. A lower stage means the cancer is small and limited to the appendix. As the cancer grows or spreads, the stages get higher.
- Stage 1. A stage 1 appendix neuroendocrine tumor is small and only in the appendix. The cancer is 2 centimeters (about 3/4 inch) or smaller at its widest point.
- Stage 2. A stage 2 cancer is larger than 2 centimeters, or it has grown deeper into the wall of the appendix. It has not spread to lymph nodes or to other parts of the body.
- Stage 3. A stage 3 cancer may be large and may have grown beyond the appendix. This stage also includes any cancer that has spread to nearby lymph nodes.
- Stage 4. A stage 4 appendix neuroendocrine tumor has spread to other parts of the body. This cancer most often spreads to the distant lymph nodes, liver, lungs and bones.
Lung neuroendocrine tumors
There are no specific stages for lung neuroendocrine tumors. Instead, these cancers use the staging for lung cancer in general. Types of lung cancer that are neuroendocrine tumors include small cell lung cancer, large cell neuroendocrine tumor and carcinoid tumor.