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Staging is a process of finding out how far a cancer
hasspread. Your treatment and prognosis (the outlook for chances of
survival) depend, to a large extent, on the cancer's stage.
Staging is based on the results of the physical exam,
biopsies, and imaging tests (CT scan, PET scan, etc.), which are
described in the section, "How
are lung carcinoid tumors diagnosed?"
The staging system for lung carcinoid tumors is the same one
used to stage non-small cell lung cancer -- the American Joint
Committee on Cancer (AJCC) TNM
staging system. The TNM system describes 3 key pieces of information:
- T
indicates the size of the main (primary) tumor and whether it
has grown into nearby areas.
- N describes
how much the cancer has spread to nearby (regional) lymph nodes. Lymph nodes
are small bean-shaped collections of immune system cells that are
important in fighting infections.
- M
indicates whether the cancer has spread (metastasized) to
other organs of the body. (The most common site is the liver.)
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.
T categories
TX:
The main (primary) tumor can't be assessed, or cancer cells were seen
on sputum cytology but no tumor can be found.
T0: There
is no evidence of a primary tumor.
Tis: The
cancer is found only in the top layers of cells lining the air
passages. It has not invaded into deeper lung tissues. This stage is
also known as carcinoma in situ.
T1: The
tumor is no larger than 3 cm (slightly less than 1¼ inches)
across, has not reached the membranes that surround the lungs (visceral
pleura), and does not affect the main branches of the bronchi.
T1a: A T1 tumor
that is 2 cm (about 4/5 of an inch) or less across.
T1b: A T1 tumor
that is larger than 2 cm but not larger than 3 cm across.
T2: The
tumor has 1 or more of the following features:
- It is between 3 cm and 7 cm across (larger than 3 cm but
not larger than 7 cm). If the tumor is 5 cm or less across (but still
larger than 3 cm), it is called
T2a. If the tumor is larger than 5 cm across (but not
larger than 7 cm), it is called T2b.
- It involves a main bronchus, but is not closer than 2 cm
(about ¾ inch) to the carina (the point where the windpipe
splits into the left and right main bronchi).
- It has grown into the membranes that surround the lungs
(visceral pleura).
- The tumor partially clogs the airways, but this has not
caused the entire lung to collapse or develop pneumonia.
T3:
The tumor has 1 or more of the following features:
- It is larger than 7 cm across.
- It has grown into the chest wall, the breathing muscle that
separates the chest from the abdomen (diaphragm), the membranes
surrounding the space between the two lungs (mediastinal pleura), or
membranes of the sac surrounding the heart (parietal pericardium).
- It invades a main bronchus and is closer than 2 cm (about
¾ inch) to the carina, but it does not involve the carina
itself.
- It has grown into the airways enough to cause an entire
lung to collapse or to cause pneumonia in the entire lung.
- Two or more separate tumor nodules are present in the same
lobe of a lung
T4: The
cancer has 1 or more of the following features:
- A tumor of any size has grown into the space behind the
chest bone and in front of the heart (mediastinum), the heart, the
large blood vessels near the heart (such as the aorta), the windpipe,
the esophagus (tube connecting the throat to the stomach), the
backbone, or the carina.
- Two or more separate tumor nodules are present in different
lobes of the same lung.
N categories
NX: Nearby
lymph nodes cannot be assessed.
N0: There
is no spread to nearby lymph nodes.
N1: The
cancer has spread to lymph nodes within the lung and/or around the area
where the bronchus enters the lung (hilar lymph nodes). Affected lymph
nodes are on the same side as the primary tumor(s).
N2: The
cancer has spread to lymph nodes around the carina (the point where the
windpipe splits into the left and right bronchi) or in the space behind
the breastbone and in front of the heart (mediastinum). Affected lymph
nodes are on the same side as the primary tumor.
N3: The
cancer has spread to lymph nodes near the collarbone on either side,
and/or spread to hilar or mediastinal lymph nodes on the side opposite
the primary tumor.
M categories
MX: Spread
to distant areas cannot be assessed.
M0:
No spread to distant organs or areas. This includes other lobes of the
lungs, lymph nodes further away than those mentioned in the N stages
above, and other organs or tissues such as the liver, bones, or brain.
M1: The
cancer has spread to 1 or more distant sites. This can be to another
lobe of the lung, to distant lymph nodes, or to other organs.
M1a: Any
of the following:
- The cancer has spread to the other lung.
- Cancer cells are found in the fluid around the lung (called
a malignant pleural
effusion).
- Cancer cells are found in the fluid around the heart
(called a malignant
pericardial effusion).
M1b: The
cancer has spread to distant organs or lymph nodes.
Stage grouping for lung cancer and lung
carcinoid
Once the T, N, and M categories have been assigned, this
information is combined (stage grouping) to assign an overall stage of
0, I, II, III, or IV. Some stages are subdivided into A and B. The
stages identify tumors that have a similar prognosis and so they are
treated in a similar way. Patients with lower stage numbers tend to
have a better prognosis.
Occult cancer
TX, N0, M0: Cancer
cells are seen in a sample of sputum or other lung fluids, but the
location of the cancer can't be determined.
Stage 0
Tis, N0, M0: The
cancer is found only in the top layers of cells lining the air
passages. It has not invaded deeper into other lung tissues and has not
spread to lymph nodes or distant sites.
Stage IA
T1, N0, M0: The
cancer is no larger than 3 cm across, has not reached the membranes
that surround the lungs, and does not affect the main branches of the
bronchi. It has not spread to lymph nodes or distant sites.
Stage IB
T2a, N0, M0: The
cancer has 1 or more of the following features:
- The main tumor is between 3 and 5 cm across (larger than 3
cm but not larger than 5 cm).
- The tumor involves a main bronchus, but is not within 2 cm
of the carina.
- The tumor has grown into the visceral pleura (the membranes
surrounding the lungs).
- The cancer is partially clogging the airways.
The cancer has not spread to lymph nodes or distant sites.
Stage IIA
There are 3 main combinations of categories that make up this
stage.
T1, N1, M0:
The cancer is no larger than 3 cm across, has not grown into the
membranes that surround the lungs, and does not affect the main
branches of the bronchi. It has spread to lymph nodes within the lung
and/or around the area where the bronchus enters the lung (hilar lymph
nodes). These lymph nodes are on the same side as the cancer. It has
not spread to distant sites.
OR
T2a, N1, M0:
The cancer has 1 or more of the following features:
- The main tumor is between 3 and 5 cm across (larger than 3
cm but not larger than 5 cm).
- The tumor involves a main bronchus, but is not within 2 cm
of the carina.
- The tumor has grown into the visceral pleura (the membranes
surrounding the lungs).
- The cancer is partially clogging the airways.
It has also spread to lymph nodes within the lung and/or
around the area where the bronchus enters the lung (hilar lymph nodes).
These lymph nodes are on the same side as the cancer. It has not spread
to distant sites.
OR
T2b, N0, M0:
The cancer has 1 or more of the following features:
- The main tumor is between 5 and 7 cm across (larger than 5
cm but not larger than 7 cm).
- The tumor involves a main bronchus, but is not within 2 cm
of the carina.
- The tumor has grown into the visceral pleura (the membranes
surrounding the lungs).
- The cancer is partially clogging the airways.
The cancer has not spread to lymph nodes or distant sites.
Stage IIB
There are 2 combinations of categories that make up this
stage.
T2b, N1, M0: The
cancer has 1 or more of the following features:
- The main tumor is between 5 and 7 cm across (larger than 5
cm but not larger than 7 cm).
- The tumor involves a main bronchus, but is not within 2 cm
of the carina.
- The tumor has grown into the visceral pleura (the membranes
surrounding the lungs).
- The cancer is partially clogging the airways.
It has also spread to lymph nodes within the lung and/or
around the area where the bronchus enters the lung (hilar lymph nodes).
These lymph nodes are on the same side as the cancer. It has not spread
to distant sites.
OR
T3, N0, M0:
The main tumor has 1 or more of the following features:
- It is larger than 7 cm across.
- It has grown into the chest wall, the breathing muscle that
separates the chest from the abdomen (diaphragm), the membranes
surrounding the space between the lungs (mediastinal pleura), or
membranes of the sac surrounding the heart (parietal pericardium).
- It invades a main bronchus and is closer than 2 cm (about
¾ inch) to the carina, but it does not involve the carina
itself.
- It has grown into the airways enough to cause an entire
lung to collapse or to cause pneumonia in the entire lung.
- Two or more separate tumor nodules are present in the same
lobe of a lung.
The cancer has not spread to lymph nodes or distant sites.
Stage IIIA
There are 3 main combinations of categories that make up this
stage.
T1 to T3, N2,
M0: The tumor can be any size or have any of the
following features
- The tumor involves a main bronchus without growing into the
carina.
- The tumor has grown into the visceral pleura (the membranes
surrounding the lungs).
- The cancer is partially clogging the airways.
- It has grown into the airways enough to cause an entire
lung to collapse or to cause pneumonia in the entire lung.
- It has grown into the chest wall, the breathing muscle that
separates the chest from the abdomen (diaphragm), the membranes
surrounding the space between the two lungs (mediastinal pleura), or
membranes of the sac surrounding the heart (parietal pericardium).
- Two or more separate tumor nodules are present in the same
lobe of a lung.
The cancer has also spread to lymph nodes around the carina
(the point where the windpipe splits into the left and right bronchi)
or in the space behind the breastbone and in front of the heart
(mediastinum). These lymph nodes are on the same side as the main lung
tumor. The cancer has not spread to distant sites.
OR
T3, N1, M0: The
tumor has 1 or more of the following features:
- It is larger than 7 cm across.
- It has grown into the chest wall, the breathing muscle that
separates the chest from the abdomen (diaphragm), the membranes
surrounding the space between the two lungs (mediastinal pleura), or
membranes of the sac surrounding the heart (parietal pericardium).
- It invades a main bronchus and is closer than 2 cm to the
carina, but it does not involve the carina itself.
- Two or more separate tumor nodules are present in the same
lobe of a lung.
- It has grown into the airways enough to cause an entire
lung to collapse or to cause pneumonia in the entire lung.
It has also spread to lymph nodes within the lung and/or
around the area where the bronchus enters the lung (hilar lymph nodes).
These lymph nodes are on the same side as the cancer. It has not spread
to distant sites.
OR
T4, N0 or N1,
M0: The cancer has 1 or more of the following features:
- A tumor of any size has grown into the space behind the
chest bone and in front of the heart (mediastinum), the heart, the
large blood vessels near the heart (such as the aorta), the windpipe,
the esophagus (tube connecting the throat to the stomach), the
backbone, or the carina.
- Two or more separate tumor nodules are present in different
lobes of the same lung.
It may also have spread to lymph nodes within the lung and/or
around the area where the bronchus enters the lung (hilar lymph nodes).
Any affected lymph nodes are on the same side as the cancer. It has not
spread to distant sites.
Stage IIIB
There are 2 combinations of categories that make up this
stage.
Any T, N3, M0:
The cancer can be of any size. It may or may not have grown into nearby
structures or caused pneumonia or lung collapse. It has spread to lymph
nodes near the collarbone on either side, and/or has spread to hilar or
mediastinal lymph nodes on the side opposite the primary tumor. The
cancer has not spread to distant sites.
OR
T4, N2, M0:
The cancer has 1 or more of the following features:
- A tumor of any size has grown into the space behind the
chest bone and in front of the heart (mediastinum), the heart, the
large blood vessels near the heart (such as the aorta), the windpipe,
the esophagus (tube connecting the throat to the stomach), the
backbone, or the carina.
- Two or more separate tumor nodules are present in different
lobes of the same lung.
The cancer has also spread to lymph nodes around the carina
(the point where the windpipe splits into the left and right bronchi)
or in the space behind the breastbone and in front of the heart
(mediastinum). Affected lymph nodes are on the same side as the main
lung tumor. It has not spread to distant sites.
Stage IV
There are 2 combinations of categories that make up this
stage.
Any T, any N,
M1a: The cancer can be any size and may or may not have
grown into nearby structures or reached nearby lymph nodes. In
addition, any of the following is true:
- The cancer has spread to the other lung.
- Cancer cells are found in the fluid around the lung (called
a malignant pleural
effusion).
- Cancer cells are found in the fluid around the heart
(called a malignant
pericardial effusion).
OR
Any T, any N,
M1b: The cancer can be any size and may or may not have
grown into nearby structures or reached nearby lymph nodes. It has
spread to distant sites, such as another organ.
Survival rates for lung carcinoid tumors
Survival rates are a way for doctors to discuss and compare
the prognosis (outlook) for patients, usually based on the stage of the
cancer or other traits. For example, the 5-year survival rate refers to
the percentage of patients who live at least 5 years after being
diagnosed (although many patients live much longer than this).
Overall, the 5-year survival rate for patients with typical
lung carcinoids is around 85% to 90%, and the 5-year survival rate for
patients with atypical lung carcinoids is around 50% to 60%. These
ranges reflect different survival rates quoted by several medical
journal articles.
Because these cancers are not common, it is hard to find
accurate survival rates based on the TNM stage of the cancer. But as a
general rule, survival rates are likely to be higher than those listed
above for people with a lung carcinoid that is still localized
(confined to the area where it started), while the rates are likely to
be lower for those with cancers that have metastasized.
Even with typical carcinoids that appear to have been treated
successfully, in a small number of cases the cancer can recur many
years later, which is why doctors often advise close follow-up for at
least 10 years.
There are some important points to keep in mind when looking
at survival rates such as the numbers above.
These numbers are derived from patients treated at least
several years ago. Improvements in treatment since then mean that the
survival rates for people now being diagnosed with these cancers may be
higher.
Survival statistics can sometimes be useful as a general
guide, but they may not accurately represent any one person's
prognosis. A number of factors other than the type and extent of the
cancer may also affect outlook, including a person's general health and
the response of the cancer to treatment.
Your doctor is likely to be a good source as to whether the
numbers above may apply to you, as he or she is familiar with the
aspects of your particular situation.
Last Medical Review: 03/09/2009 Last Revised: 03/09/2009
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