Detailed Guide: Esophagus Cancer
How Is Cancer of the Esophagus Staged?
Staging is the process of finding out how far a cancer has spread. The treatment and outlook for people with esophageal cancer depend, to a great extent, on the cancer's stage.
Esophageal cancer is staged with the imaging tests described above, combined with endoscopy and biopsy.
The most common system used to stage esophageal cancer is the TNM system of the American Joint Committee on Cancer (AJCC). The TNM system describes 3 key pieces of information. T refers to the size of the primary tumor and how far it has spread within the esophagus and to nearby organs. N refers to cancer spread to nearby lymph nodes. M indicates whether the cancer has metastasized (spread to distant organs).
Tis
The cancer is only in the epithelium (the top layer of cells lining the esophagus). It has not started growing into the deeper layers. This stage is also known as carcinoma in situ.
T1
The cancer is growing into the tissue under the epithelium, such as the lamina propria or submucosa.
T2
The cancer is growing into the muscle layer (muscularis propria).
T3
The cancer is growing into the outer layer of tissue covering the esophagus (the adventitia).
T4
The cancer is growing into nearby structures, such as the trachea (windpipe), the pleura (the tissue covering the lungs), or the tissue covering the heart (the pericardium).
N0
The cancer has not spread to nearby lymph nodes.
N1
The cancer has spread to nearby lymph nodes.
M0
The cancer has not spread to distant organs or lymph nodes.
M1a
The cancer has spread to distant lymph nodes but not to other organs.
M1b
The cancer has spread to distant organs.
Information about the tumor, lymph nodes, and any cancer spread is then combined to assign the stage of disease. This process is called stage grouping. The stages are described using the number 0 and Roman numerals from I to IV:
This is the earliest stage of esophageal cancer. The cancer cells are only found in the epithelium (the layer of cells lining of the esophagus). The cancer has not grown into the connective tissue beneath these cells. The cancer has not spread to lymph nodes or other organs. This stage is also called carcinoma in situ.
The cancer has grown from the epithelium into the connective tissue underneath (the lamina propria). It may also have grown through that tissue into the layer below (the submucosa), but it has not grown any deeper. It has not spread to lymph nodes or to distant sites.
This stage is split into 2 substages, stage IIA and stage IIB.
Stage IIA (T2 or 3, N0, M0):
The cancer has grown into the muscle layer called the muscularis propria (T2). It may also have grown through the muscle layer into the adventitia, the connective tissue covering the outside of the esophagus (T3). The cancer has not spread to lymph nodes or to distant sites.
Stage IIB (T1 or 2, N1, M0):
The cancer has grown into the lamina propria (T1). It may also have grown into layers below: the submucosa (T1) and the muscularis propria (T2). It has not grown through to the outer layer of tissue covering the esophagus. It has spread to lymph nodes near the esophagus (N1) but has not spread to lymph nodes farther away from the esophagus or to distant sites.
Either
The cancer has grown through the wall of the esophagus to its outer layer, the adventitia (T3). It has spread to lymph nodes near the esophagus (N1), but has not spread to lymph nodes farther away from the esophagus or to distant sites
OR
The cancer has grown all the way through the esophagus and into nearby organs or tissues (T4). It may also have spread to nearby lymph nodes, but has not spread to lymph nodes farther away from the esophagus or to distant sites.
This is split into 2 substages, stage IVA and stage IVB
Stage IVA (any T, any N, M1a):
The cancer has spread to distant lymph nodes (M1a). If the esophageal cancer is in the upper part of the chest, these lymph nodes are in the neck. For cancers of the lower part of the esophagus, these lymph nodes are in the abdomen. The cancer has not spread to distant organs or tissues.
Stage IVB (any T, any N, M1b):
The cancer has spread to distant sites, such as the liver, bones, brain, or more distant lymph nodes (M1b).
Survival rates by stage
These numbers describe the outcomes of patients diagnosed several years ago (prior to 2000).
| Stage | 5-Year Relative Survival Rate |
| I | 50 to 80% |
| IIA | 30 to 40% |
| IIB | 10 to 30% |
| III | 10 to 15% |
| IV | less than 5% |
The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Five-year rates are used to produce a standard way of discussing prognosis. Of course, many people live much longer than 5 years. The 5-year relative survival rate assumes that people will die of other causes and compares the observed survival with that expected for people without this cancer. This is a better way to look at deaths from esophageal cancer. Keep in mind that these rates are from people diagnosed and treated many years ago. Treatment and care has improved since that time, and people diagnosed today may have better outcomes.
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