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Staging is the process of finding out how far a cancer
hasspread. Once penile cancer is diagnosed, your doctor will determine
the
stage of the cancer using the results of exams, biopsies, and any
imaging tests you have had. (These were described in the section, "How
is penile cancer diagnosed?") The stage of your cancer is a
very important factor in planning your treatment and estimating your
prognosis (outlook).
If you have penile cancer, ask your cancer care team to
explain staging in a way that you can understand. Knowing all you can
about staging will let you take a more active role in making informed
decisions about your treatment.
The American Joint Committee on Cancer
(AJCC) TNM system
A staging system is a standardized way for the cancer care
team to summarize information about how far a cancer has spread. The
most common system used to describe the stages of squamous cell penile
cancers is the American Joint Committee on Cancer (AJCC) TNM system.
This system is based on 3 key pieces of information:
- T
stands for tumor
(how far it has spread within the penis and to nearby organs).
- N
stands for spread to nearby lymph nodes
(bean-sized collections of immune system cells that help fight
infections and cancers).
- M
is for metastasis
(spread to distant organs).
Additional letters or numbers 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" after the T
stand for "in situ," which means the cancer is only in the top layers
of skin and has not yet invaded (grown into) a deeper layer of tissue.
The type of staging described here is known as surgical or pathologic
staging. This type of staging is based on the results of biopsies and
the findings at surgery. Penile cancer can also be clinically staged.
Clinical staging is based on the results of a physical exam and imaging
studies (such as CT scans).
Another factor that can affect staging is the grade of the
cancer. The grade is a measure of how abnormal the cancer cells appear
when they are examined under a microscope. The grade can be expressed
as a number, from 1 to 4. The higher the number, the more abnormal the
cells look. Higher grade cancers tend to grow and spread more quickly
than lower grade cancers.
T categories:
TX: Primary
tumor cannot be assessed
T0:
No evidence of primary tumor
Tis:
Carcinoma in situ (cancer that is only in the top layers of skin)
Ta:
Verrucous (wart-like) carcinoma that is only in the top layers of skin
T1:
Tumor has grown into the tissue below the top layers of skin (called
the subepithelial connective tissue)
T1a: The cancer has
grown into the subepithelial connective tissue, but it has not grown
into blood or lymph vessels. The cancer is grade 1 or 2.
T1b: The cancer has
grown into the subepithelial connective tissue and either it has grown
into blood and lymph vessels OR it is high-grade (grade 3 or 4).
T2:
Tumor has grown into one of the internal chambers of the penis (the
corpus spongiosum or corpora cavernosum)
T3:
Tumor has grown into the urethra (the tube that carries urine and semen
outside of the body)
T4:
Tumor has grown into the prostate or other nearby structures
N categories
NX: Nearby
lymph nodes cannot be assessed
N0:
No spread to nearby lymph nodes
N1:
The cancer has spread to a single lymph node in the groin (inguinal
lymph node)
N2:
The cancer has spread to more than 1 inguinal lymph node
N3:
The cancer has spread to lymph nodes in the pelvis and/or the cancer in
the lymph nodes has grown through the outer covering of the lymph node
and into the surrounding tissue
M categories
MX: Cannot
tell if the cancer has spread to distant organs or tissues
M0:
The cancer has not spread to distant organs or tissues
M1:
The cancer has spread to distant organs or tissues (such as lymph nodes
outside of the pelvis, lungs, or liver)
Using the TNM system, a doctor might describe one case of
penile cancer as T2, N0, M0 and another as T4, N1, M0.
Stage groupings
To summarize this information, TNM combinations are grouped
together into a simpler set of stages, labeled stage 0 through stage
IV. This is known as stage grouping.
Stage 0: Tis or Ta, N0, M0:
The cancer has not grown into tissue below the top layers of
skin and has not spread to lymph nodes or distant sites.
Stage I: T1a, N0, M0:
The cancer has grown into tissue just below the superficial
layer of skin but has not grown into blood or lymph vessels. It is a
grade 1 or 2. It has not spread to lymph nodes or distant sites.
Stage II Any of the following:
T1b, N0, M0: The
cancer has grown into tissue just below the superficial layer of skin
and is either high-grade or has grown into blood or lymph vessels. It
has not spread to lymph nodes or distant sites
OR
T2, N0, M0:
The cancer has grown into one of the internal chambers of the penis
(the corpus spongiosum or corpora cavernosum). The cancer has not
spread to lymph nodes or distant sites.
OR
T3, N0, M0:
The cancer has grown into the urethra. It has not spread to lymph nodes
or distant sites.
Stage IIIa: T1 to T3, N1, M0:
The cancer has grown into tissue below the superficial layer
of skin (T1). It may also have grown into the corpus spongiosum, the
corpus cavernosum, or the urethra (T2 or T3). The cancer has spread to
a single groin lymph node (N1). It has not spread to distant sites.
Stage IIIb: T1 to T3, N2, M0:
The cancer has grown into the tissues of the penis and may
have grown into the corpus spongiosum, the corpus cavernosum, or the
urethra (T1 to T3). It has spread to 2 or more groin lymph nodes. It
has not spread to distant sites
Stage IV: Any of the following:
T4, any N, M0:
The cancer has grown into the prostate or other nearby structures. It
may or may not have spread to groin lymph nodes. It has not spread to
distant sites.
OR
Any T, N3, M0: The
cancer has spread to lymph nodes in the pelvis OR the cancer spread in
the groin lymph nodes has grown through the lymph nodes' outer covering
and into the surrounding tissue. The cancer has not spread to distant
sites.
OR
Any T, any N, M1: the cancer has spread to distant sites.
Recurrent cancer
Recurrent disease means that the cancer went away with
treatment, but then later came back. Recurrent penile cancer may return
in the penis or in any other part of the body. This isn't a formal
stage of the TNM system, but a doctor may note it by putting a small
'r' in front of the stage (for example, rT2N1M0).
Survival rates for penile cancer
Survival rates are a way for doctors and patients to get a
general idea of the outlook for people with a certain type and stage of
cancer. Some people want to know the statistics for people in their
situation, while others may not find them helpful, or may even not want
to know them. Whether or not you want to read about the survival
statistics below for penile cancer is up to you.
Survival rates are typically 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 a person's age and general
health, and how well the cancer responds to treatment. Your doctor can
tell you if the numbers below may apply to you, as he or she is
familiar with the aspects of your particular situation.
The 5-year survival rate is the percentage of patients who live at least five
years after their cancer is diagnosed. Many of these patients live much
longer than five years, but 5-year rates are used to produce a standard
way of discussing prognosis (outlook). Relative survival
rates compare the survival of people with the cancer to the survival
for people without the cancer. Since some people will die of causes
other than cancer, this is a way to look only at deaths from the cancer
in question. The 5-year relative survival rate is a more accurate way
to describe the outlook for patients with a particular type and stage
of cancer.
Because penile cancer is not common, it is hard to find
accurate survival rates based on the TNM stage of the cancer. The
numbers below come from the National Cancer Institute's SEER database,
looking at more than 1,000 men diagnosed with penile cancer between
1988 and 2001. These men were diagnosed at least several years ago, so
men now being diagnosed may have a better outlook.
- For cancers that are still confined to the penis, the
5-year relative survival rate is around 85%.
- If the cancer has spread to nearby tissues or lymph nodes,
the 5-year relative survival rate is around 59%.
- If the cancer has spread to distant parts of the body,
5-year relative survival rate is about 11%.
Last Medical Review: 10/07/2009 Last Revised: 10/07/2009
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