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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).
T stages
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).
N stages
N0
The cancer has not spread to nearby lymph nodes.
N1
The cancer has spread to nearby lymph nodes.
M stages
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:
Stages
Stage 0 (Tis, N0, M0)
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.
Stage I (T1, N0, M0)
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.
Stage II
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.
Stage III (T3, N1, M0; OR T4, N0 or 1, M0)
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.
Stage IV
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 |
| 0 |
>95% |
| 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.
Last Medical Review: 05/04/2009 Last Revised: 05/13/2009
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