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Salivary Gland
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Salivary gland
cancer is a type of
cancer that can occur in
any of the glands located on the face which produce saliva.
These include the parotid glands, submandibular glands and
sublingual glands. Parotid glands are the largest glands and
account for 70 percent of all
cancers of salivary
gland
cancer.
Sub-mandibular glands are found in the back of the jaw and are
the origin for 20 percent of salivary gland cancers. Finally,
sublingual glands are rarely the starting point of
cancer. |
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There are also hundreds of other smaller salivary
glands that line parts of the lips, tongue and
inside of the cheek. Tumors in these small
glands are extremely rare, and when they do
occur, they are usually malignant. |
Benign Salivary Gland Tumors:
Most tumors that occur in salivary glands are
benign or non-cancerous. They do not spread to
other parts of the
body and
they are rarely life threatening. There are
several different forms of benign salivary gland
tumors, including adenomas, oncocytomas, Warthin
tumor, and pleomorphic adenoma, a type of mixed
benign tumor. When a patient has a benign
salivary gland tumor, he or she usually has
surgery performed to remove it. This is
important because in some instances, a benign
tumor may become cancerous.
Malignant Salivary Gland Tumors:
There are many different types
of salivary gland cancers which
are classified depending on the shape and
structure of the cells when viewed under a
microscope. To help doctors understand the
seriousness of the
cancer
itself, they usually classify it into one of
three different categories called grades. These
grades help determine how fast the
cancer
will grow and spread in a patient's
body.
Grade 1:
Grade 1 salivary cancers are defined as having a
well-differentiated structure because they have
a structure that is similar to normal glandular
cells found in the salivary glands. They grow
very slowly and generally have a positive
prognosis for patients who are diagnosed with
this type of
cancer.
Grade 2:
Grader 2 salivary
cancers are in the mid-range in terms of growth
speed. They are considered to be moderately
differentiated from normal cells and carry a
prognosis between grade 1 and grade 3 salivary
cancers.
Grade 3:
Grade 3 salivary cancers are high
grade and are considered to be poorly
differentiated. When viewed under a microscope,
grade 3
cancer cells look very different from normal
cells. Their growth rate is very fast and can
easily spread to other parts of the
body.
The prognosis for grade 3 cancers is generally
poor. |
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Types of Salivary Gland Cancers:
A biopsy
is used to help a doctor determine which type of
salivary gland
cancer a
patient has. Since different types of cells are
found within these glands, the type of
cancer
found can be one of the following possible
types:
|Mucoepidermoid
Carcinoma |
Adenoid
Cystic Carcinoma |
Adenocarcinoma
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There are
also more types of salivary gland
cancer,
though they are extremely rare:
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Squamous
Cell Carcinoma
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Epithelial-Myoepithelial Carcinoma
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Anaplastic Small Cell Carcinoma
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Undifferentiated Carcinomas
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Non-Hodgkin Lymphoma
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Doctors
may sometimes have difficulty classifying a type
of salivary gland
cancer
because the cells are very hard to distinguish
from their physical properties. Malignant mixed
tumors are types of malignant salivary gland
cancers that fall within this spectrum. They
include:
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Carcinoma
ex pleomorphic adenoma
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Carcinosarcomas
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Metastasizing mixed tumor
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Salivary Gland Cancer Causes:
A great
amount of research has been done on DNA in
salivary gland cells and how abnormalities in a
cell's genes can lead to the development of
cancer.
Scientists believe that tumor suppression genes
may become damaged, causing cells to divide
uncontrollably. The main causes of
cancer
are exposure to radiation or what are known as
carcinogens. Carcinogens are usually chemicals
that have been known to alter DNA in cells,
causing the development of
cancer.
Unfortunately,
cancer
forms mysteriously and much research is needed
to understand exactly how DNA becomes damaged.
The exact cause of salivary gland
cancer
is still being researched by scientists and
physicians. Fortunately, there are a number of
risk factors that are known to aid in the
development of
cancer.
Avoiding risk factors will ensure that one lives
a normal,
cancer-free life. Risk factors include:
Radiation Exposure:
A person may be exposed to radiation through a
number of different means. This can include
dangerous work environments, but can also come
from radiation treatment a person receives to
treat another type of
cancer
he or she may have.
Family History:
Research suggests
that a person may be more likely to develop
cancer
if they have a family history of
cancer.
This helps support evidence that a person's likelihood of developing
cancer
is carried in his or her genes.
Tobacco and
Alcohol:
Tobacco, one of the most widely known
carcinogens, and alcohol can contribute to the
development of
cancer.
Diet:
A healthy diet rich in vegetables and low in
animal fat will help prevent a person from
developing
cancer of any kind.
Cell Phones:
A great deal of research is being
done on cell phones and their link to
cancer,
especially salivary gland
cancer. |
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Prevention of Salivary Gland Cancer:
Salivary gland
cancer
prevention focuses heavily on avoiding the risk
factors as described above. This includes eating
a healthy diet, avoiding common carcinogens such
as alcohol and tobacco, and avoiding all other
hazardous materials that have been linked with
the development of
cancer
Salivary Gland Cancer Symptoms:
Salivary
gland
cancer
is generally rare and begins in the face and
neck area of a person where the salivary glands
are located. Fortunately, salivary gland
cancer
has very noticeable symptoms that aid a patient
in discovering it relatively early. The most
common symptoms is an abnormal swelling on the
side of face and neck area, which may form into
a lump in the neck and throat area. Other
symptoms include:
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Facial
Palsy (droopiness of the face)
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Pain |
Difficulty swallowing
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Trouble moving jaw
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Diagnosis of Salivary Cancer:
After a patient sees a doctor when experiencing
symptoms of salivary gland
cancer,
there are several tests a doctor will perform.
Seeing a doctor will include a physical exam as
well as an examination of the mouth and neck
areas of the patient. After the findings of the
examine are determined, the doctor may order
further tests to be done. The two main ways a
doctor will test for salivary gland
cancer
Imaging Tests:
The
simplest and most common form of imaging test is
an x ray. Salivary gland
cancer
is one of the few
cancers
that can easily be seen through a common x ray.
The x ray can help show the presence of any
abnormalities found in the jaw and upper neck
areas.
There are
three common advanced imaging tests that may
need to be performed as well to create a more
detailed image of a persons face and neck area.
The first is a CT scan, an imaging test that
produces more powerful x rays to create cross
sectional images of a patient's face and neck.
This can be used to create a detailed image of
the size, shape and exact position of a possible
tumor. Next, an MRI test gathers a detailed
image through the use of radio waves. MRIs can
tell a doctor if a tumor is benign or malignant.
Finally, a PET scan uses a special camera that
picks up radioactivity absorbed by a patient's
body
Biopsy:
The
biopsy helps a doctor determine for sure if a
tumor is benign, malignant, or if a tumor is
even present within a patient. It can help
doctors find pre-cancerous conditions as well so
that
cancer |
The Staging of Salivary Cancer:
Like most cancers, salivary
cancer
is staged through the TNM system created by the
American Joint Committee on
Cancer.
The reason for a doctor to stage a patient cancer
is to determine how advanced the tumor is so
that a prognosis can be formed along with a
course of treatment.
For example, if a
cancer
is determined to be in stage II, surgery may
be an elected course of treatment along with a follow-up treatment of radiation
therapy.
In order for a
cancer
to be staged, the
cancer
is measured in three different dimensions.
First, the size of the tumor is determined (T).
Next, the presence of
cancer
cells in nearby lymph nodes are measured (N).
Lastly, the
cancer is searched for in distant parts of
the
body
to see if it has metastasized (M). The
cancer
is then put into one of four stages (I-IV) based
on the results of these three tests.
Salivary Cancer Prognosis:
The prognosis a
doctor formulates is an educated guess about the
outcome of a case of salivary gland
cancer.
The prognosis may also help affect the treatment
options that are available as well. One of the
biggest determinants of the prognosis is the
stage of the
cancer. The higher the stage, the poorer the
prognosis. The grade of the
cancer
is another large factor. The prognosis is
usually measured in a five year survival rate.
This determines the number of patients that
survive for five years or longer after being
diagnosed with salivary
cancer
Treatment of Salivary Cancer:
The treatment of salivary
cancer
is largely based on the stage of the
cancer.
After the stage is measured, a course of
treatment, depending on what is available, will
be selected by a doctor. Generally, surgery is
the most used option, especially in early
stages, though options become more limited in
stage IV salivary gland
cancer
Surgery:
A treatment option
available in stages I through III of salivary
gland
cancer,
salivary gland surgery is designed to remove the
tumor along with surrounding tissues which may
contain cancerous cells. In addition, a doctor
may remove the entire salivary gland from the
patient, along with lymph nodes from the neck.
Surgery is almost always followed up with
radiation therapy as well to help kill remaining
cancer
Radiation
Therapy:
Radiation therapy in salivary
cancer
can either be used as a primary treatment or a
secondary follow up treatment to surgery. When
used as a primary treatment, it is sometimes
combined with chemotherapy. A doctor elects this
method usually if the
cancer
is in stage IV and surgery is not possible. When
it is used after surgery, it is done to kill
remaining
cancer
Chemotherapy:
Chemotherapy is generally not
used often in treatment of salivary gland
cancer,
especially in earlier stages of the
cancer.
It may be used, however, in stage IV
cancer
when it has spread to other parts of the
body and
in conjunction radiation therapy to shrink the
tumor and relieve symptoms for a patient.
Chemotherapy targets cells in the
body
which divide rapidly. This includes
cancer |
Salivary Gland Cancer Research:
Though research for
salivary
cancer continues, it is difficult to
perform because salivary
cancer is a relatively rare form of
cancer. Research continues in
clinical trials for development of new
treatments, though improvements to
currently existing treatments is also
being developed. Improvements to
currently existing treatments include:
Surgery:
As surgery techniques
and technologies improve, researchers
have found that surgery done by head and
neck doctors to remove
cancer at the base of the skull is
now possible. A few years ago, most
doctors would not even attempt to
perform this operation, but today, it is
done often and is usually successful.
Radiation Therapy:
Radiation therapy
research continues to find more advanced
techniques to make it more accurate,
protecting normal healthy cells are the
tumor. This is done with precision
machines and tumor mapping to ensure
that only tumor cells are killed by the
treatment.
Chemotherapy:
More drugs are being
developed and tested for salivary gland
cancer. Also, combinations of
currently existing drugs are being
tested for added effectiveness.
Targeted Therapy:
As gene research has become more
widespread, new forms of
cancer treatment have taken shape.
One promising treatment is targeted
therapy, which was developed as
researchers understood the changes that
take place in cells that develop into
cancer. Targeted therapy uses drugs
specifically designed to affect these
changes. |
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