Staging -- or determining the stage of disease -- is theprocess of finding out the extent of disease. It tells us if the tumor has spread, and if it has, how far. To help stage the tumor, doctors may use several types of imaging, endoscopy, or other tests described in the previous section, "How are gastrointestinal carcinoid tumors diagnosed?"

The stage of the tumor, along with the place it started, tell us about the prognosis (outlook) for someone with a gastrointestinal (GI) carcinoid. tumor. These 2 factors also help the doctor decide what treatment to recommend.

Localized, regional, and distant stages

GI carcinoid tumors/cancers can start in several different locations, and until recently there had been no standard system for describing their spread. In the past, many doctors simply divided GI carcinoid tumors into 3 general stages: localized, regional spread, and distant spread. This approach is fairly easy to understand and can be useful when choosing between treatment options. Because the cells can look the same under the microscope, it might not be possible to tell a benign tumor from a cancer when it is localized. Any tumor that spreads, though, is a cancer (by definition).

Localized

The cancer has not spread beyond the wall of the organ it started in (for example, the stomach, intestine, or rectum).

Regional spread

The cancer has grown through the wall of the organ where it started to involve nearby tissues such as fat, ligaments, and muscle. It may also have spread to nearby lymph nodes.

Distant spread

The cancer has spread to tissues or organs that are not near the organ where the cancer started (such as the liver, bones, or lungs).

The AJCC TNM system

Modern staging of GI carcinoid tumors/cancers uses a system created by the American Joint Committee on Cancer (AJCC) that is known as the TNM system. The TNM system for staging contains 3 key pieces of information:

• T describes the size of the primary tumor, measured in centimeters (cm), and whether the cancer has spread to organs next to the tumor.
• N describes the extent of spread to nearby (regional) lymph nodes.
• M indicates whether the cancer has metastasized (spread) to other organs of the body.

Numbers or letters appear after T, N, and M to provide more details about each of these factors:

• The numbers 0 through 4 indicate increasing severity.
• The letter X means "cannot be assessed" because the information is not available.
• The letters "is" mean "carcinoma in situ," which means the tumor is contained within the top layer of cells and has not yet reached deeper layers of tissue.

The T categories for GI carcinoid cancers differ depending on where the cancer starts, but the N and M categories are the same. Once the T, N, and M categories for a tumor are known, the information is combined to determine the overall stage. This process is known as stage grouping.

T categories for carcinoid tumors of the stomach

The T category describes how far down through the stomach layers the cancer has grown. The wall of the stomach is made of 5 layers. The innermost layer is the mucosa. This is where stomach acid and digestive enzymes are made. The mucosa has 3 parts: epithelial cells, which lie on top of a layer of connective tissue (the lamina propria), which is on top of a thin layer of muscle (the muscularis mucosa). Under the mucosa is a supporting layer called the submucosa. This is surrounded by the muscularis, a layer of muscle that moves and mixes the stomach contents. The next 2 layers, the subserosa and the outermost serosa, act as wrapping layers for the stomach.

TX: Primary (main) tumor cannot be assessed due to incomplete information

T0: The primary tumor cannot be found:

Tis: The tumor is less than 0.5 mm (about half the width of a grain of rice) and the cancer cells are found only in the top layer of cells of the stomach lining. This is also known as carcinoma in situ or severe dysplasia.

T1: The tumor has grown from the top layer of cells and into deeper layers, such as the lamina propria or the submucosa. The tumor is 1 cm (less than half of an inch) or less in size.

T2: Either:

The tumor has grown into the lamina propria or submucosa (or both) and is greater than 1 cm in size.

OR

The tumor has grown through the lamina propria and submucosa and into the main muscle layer of the stomach (called the muscularis propria).

T3: The tumor has grown through the muscularis propria and into the subserosa.

T4: The tumor has grown into the serosa (the outer layer of tissue covering the stomach, also called the visceral peritoneum) or into nearby organs or structures.

T categories for carcinoid tumors of the small intestine

T categories of small intestine cancer describe the extent of spread through the layers that form its wall.

The innermost layer of the intestine is known as the mucosa. It has 3 parts: the top layer of cells (called the epithelium), a thin layer of connective tissue (called the lamina propria), and a thin layer of muscle. The other layers, from the inner to the outer, include, the fibrous tissue beneath the mucosa (submucosa), a thick layer of muscle that contracts to force the contents of the intestines along (muscularis propria), and the thin outermost layers of connective tissue (subserosa and serosa) that cover the small intestine. The serosa is also known as the visceral peritoneum.

TX: Primary (main) tumor cannot be assessed.

T0: The primary tumor cannot be found.

T1: The tumor has grown from the top layer of cells and into deeper layers, such as the lamina propria or the submucosa. The tumor is 1 cm (less than half of an inch) or less in size.

T2: Either:

The tumor has grown into the lamina propria or submucosa (or both) and is greater than 1 cm in size.

OR

The tumor has grown through the lamina propria and submucosa and into the main muscle layer of the colon (called the muscularis propria).

T3: The tumor has grown through the muscularis propria and into the subserosa, the pancreas, and/or the retroperitoneum (the area in back of the abdomen).

T4: The tumor has grown into the serosa (the outer layer of tissue covering the intestine, also called the visceral peritoneum) or into nearby organs.

T categories for carcinoid tumors of the colon or rectum

T categories for carcinoid tumors of the colon and rectum cancer describe the extent of spread through the layers that form its wall. The innermost layer is known as the mucosa. It has 3 parts: the top layer of cells (called the epithelium), a thin layer of connective tissue (called the lamina propria), and a thin layer of muscle. The other layers, from the inner to the outer, include, the fibrous tissue beneath the mucosa (submucosa), a thick layer of muscle that contracts to force the contents of the intestines along (muscularis propria), and the thin outermost layers of connective tissue (subserosa and serosa) that cover the small intestine. The serosa is also known as the visceral peritoneum.

TX: Primary (main) tumor cannot be assessed due to incomplete information.

T0: The primary tumor cannot be found.

T1: The tumor has grown from the top layer of cells and into deeper layers, such as the lamina propria or the submucosa. The tumor is 2cm (about 4/5 of an inch) or less in size.

T1a: The tumor is less than 1 cm across (1 cm is less than half of an inch).

T1b: The tumor is 1 to 2 cm across in size.

T2: either

The tumor has grown into the lamina propria or submucosa (or both) and is greater than 2 cm in size.

OR

The tumor has grown through the lamina propria and submucosa and into the main muscle layer of the colon (called the muscularis propria).

T3: The tumor has grown through the muscularis propria and into the subserosa or other tissue around the colon or rectum.

T4: The tumor has grown through the wall of the colon (or rectum) and into the serosa (also called peritoneum) and/or into nearby organs.

T categories for carcinoid tumors of the appendix

TX: Primary (main) tumor cannot be assessed.

T0: No signs of a primary tumor.

T1: The tumor is no more than 2 cm (2 cm is about 4/5 of an inch) across.

T1a: The tumor is no more than 1 cm across (1 cm is a little less than half of an inch).

T1b: The tumor is larger than 1 cm but not larger than 2 cm across.

T2: Either:

The tumor is larger than 2 cm but not larger than 4 cm.

OR

The tumor has grown into the cecum (the first part of the large intestine.

T3: Either:

The tumor is larger than 4 cm.

OR

The tumor has grown into the ileum (the last part of the small intestine).

T4: The tumor has grown into nearby organs or tissues (such as the abdominal wall).

N categories for GI arcinoid tumors/cancers

NX: Spread to nearby (regional) lymph nodes cannot be assessed.

N0: No spread to nearby lymph nodes.

N1: The cancer has spread to nearby lymph nodes.

M categories for GI carcinoid tumors/cancers

M0: No spread (metastasis) to distant organs or structures.

M1: The cancer has spread (metastasis) to distant organs or structures (such as the liver, lungs, bones, etc).

Stage groupings for carcinoid of the stomach

Stage 0: Tis, N0, M0: Carcinoma in situ: the tumor is less than 0.5 mm (and the cancer cells are found only in the top layer of cells of the stomach lining (Tis). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage I: T1, N0, M0: The tumor is 1 cm or less in size and has grown from the top layer of cells and into deeper layers, such as the lamina propria or the submucosa (T1). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIA: T2, N0, M0: Either the tumor has grown into the lamina propria or submucosa (or both) and is greater than 1 cm in size; OR the tumor has grown into the main muscle layer of the stomach (called the muscularis propria) (T2). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIB: T3, N0, M0: The tumor has grown through the muscularis propria and into the subserosa (T3). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIIA: T4, N0, M0: The tumor has grown into the outer layer of tissue covering the stomach (the serosa or visceral peritoneum) or into nearby organs or structures. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIIB: any T, N1, M0: The tumor can be any size and may or may not have grown into nearby structures (any T). It has spread to nearby lymph nodes (N1), but not to distant sites (M0).

Stage IV: any T, any N, M1: The tumor can be any size and may or may not have grown into nearby structures (any T). It may or may not have spread to nearby lymph nodes (any N). The cancer has spread to distant sites (most often the liver).

Stage groupings for carcinoid of the small intestine

Stage I: T1, N0, M0: The tumor is 1 cm or less in size and has grown from the top layer of cells and into deeper layers, such as the lamina propria or the submucosa (T1). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIA: T2, N0, M0: Either the tumor has grown into the lamina propria or submucosa (or both) and is greater than 1 cm in size; OR the tumor has grown into the main muscle layer of the intestine (called the muscularis propria) (T2). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIB: T3, N0, M0: The tumor has grown through the muscularis propria and into the subserosa (T3). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIIA: T4, N0, M0: The tumor has grown into the outer layer of tissue covering the intestine (the serosa or visceral peritoneum) or into nearby organs or structures. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIIB: any T, N1, M0: The tumor can be any size and may or may not have grown into nearby structures (any T). It has spread to nearby lymph nodes (N1), but not to distant sites (M0).

Stage IV: any T, any N, M1: The tumor can be any size and may or may not have grown into nearby structures (any T). It may or may not have spread to nearby lymph nodes (any N). The cancer has spread to distant sites (most often the liver)

Stage groupings for carcinoid of the colon and rectum

Stage I: T1, N0, M0: The tumor is 2cm (about 4/5 of an inch) or less in size and has grown into the lamina propria and may have grown into the submucosa. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIA: T2, N0, M0: either the tumor has grown into the lamina propria or submucosa (or both) and is greater than 2 cm in size; OR the tumor has grown into the main muscle layer of the colon (called the muscularis propria). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIB: T3, N0, M0: The tumor has grown through the muscularis propria and into the subserosa or other tissue around the colon or rectum. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIIA: T4, N0, M0: The tumor has grown through the wall of the colon (or rectum) and into the serosa (also called peritoneum) and/or into nearby organs. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage IIIB: any T, N1, M0: The tumor can be any size and may or may not have grown into nearby structures (any T). It has spread to nearby lymph nodes (N1), but not to distant sites (M0).

Stage IV: any T, any N, M1: The tumor can be any size and may or may not have grown into nearby structures (any T). It may or may not have spread to nearby lymph nodes (any N). The cancer has spread to distant sites (most often the liver)

Stage groupings for carcinoid tumors of the appendix

Stage I: T1, N0, M0: The tumor is no more than 2 cm in size. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage II: T2 or T3, N0, M0: the tumor is either larger than 2 cm or it has grown into the cecum (T2) or ileum (T3). The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

Stage III: either

T4, N0, M0: The tumor has grown into nearby organs or tissues. The cancer has not spread to nearby lymph nodes (N0) or to distant sites (M0).

OR

Any T, N1, M0: The tumor can be any size and may or may not have grown into nearby structures (any T). It has spread to nearby lymph nodes (N1), but not to distant sites (M0).

Stage IV: Any T, any N, M1: The tumor can be any size and may or may not have grown into nearby structures (any T). It may or may not have spread to nearby lymph nodes (any N). The cancer has spread to distant sites (most often the liver).

5-year survival rates by stage and primary site

Survival rates are often used by doctors as a standard way of discussing a person's prognosis (outlook). Some patients with cancer may want to know the survival statistics for people in similar situations, while others may not find the numbers helpful, or may even not want to know them. Whether or not you want to read about the survival statistics below for gastrointestinal carcinoid tumors is up to you.

The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Of course, many people live much longer than 5 years (and many are cured).

In order to get 5-year survival rates, doctors have to look at people who were treated at least 5 years ago. Improvements in treatment since then may result in a more favorable outlook for people now being diagnosed with (cancer).

Survival rates are often based on previous outcomes of large numbers of people who had the disease, but they cannot predict what will happen in any particular person's case. Many other factors may affect a person's outlook, such as the grade of the tumor, the patient's age and health, and how well the cancer responds to treatment. Your doctor can tell you how the numbers below may apply to you, as he or she is familiar with the aspects of your particular situation.

Most GI carcinoid tumors are found when they are still localized, but this does vary based on the organ they start in. Tumors of the stomach, duodenum, appendix, and rectum are likely to be found before they have spread. In contrast, many tumors of the small intestine (the jejunum/ileum) and the colon (including the cecum) have already spread to nearby tissues or lymph nodes or to distant sites at the time of diagnosis.

The following 5-year survival rates are based on people diagnosed with carcinoid (well and moderately differentiated neuroendocrine tumors) between 1988 and 2004:

5-year Survival Rates, by Stage and Primary Site

It is important to keep in mind that the numbers above are merely statistics and they can't predict the outlook for any one person.

Last Medical Review: 06/19/2009
Last Revised: 06/19/2009