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Statistical
Information
Risk Factors
Signs & Symptom
Early Detection
Figure 1. VELscope examination. The clinician
shines the blue excitation light into the patients oral
cavity and looks through the Handpiece.

Figure 2. Illustration of VELscopes
principle of operation.

Figure 3. Representative examples of direct
visualization under both white light and VELscope examination
- photos courtesy of the British Columbia Oral Cancer Prevention
Program.
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No apparent lesion
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Normal fluorescence pattern
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Visible leukoplakia
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Irregular, dark area visible under
fluorescence visualization. Biopsy-confirmed severe
dysplasia
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No apparent lesion
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Irregular, dark area visible under
fluorescence visualization. Biopsy-confirmed Carcinoma
in Situ (CIS)
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Statistical Information
Every hour of every day in America someone
dies of Oral Cancer. Oral Cancer is the sixth most common
diagnosed form of cancer in the United States. Presently 30,000
patients are diagnosed annually with oral cancer. The 5-year
survival rate is only 50%, accounting for 8,000 deaths each
year. Oral Cancer risk factors include tobacco use, frequent
and/or excessive alcohol consumption, a compromised immune
system, past history of cancer, and the presence of the HPV
virus. Recently however 25% of all newly diagnosed cases have
been in patients under the age of forty with none of the known
risk factors. Oral Cancer is one of the few cancers whose
survival rate has not improved in the past 50 years. This
is due primarily to the fact that during this time we have
not changed the way we screen for this disease (a visual and
manual examination of the oral cavity, head, and neck).
Oral Squamous Cell Carcinomas (OSCC) make
up over 90% of all oral cancers, and because of its appearance
it has been difficult to differentiate from the other relatively
benign lesions of the oral cavity. Early OSCC and potentially
malignant lesions can appear as a white patch (leukoplakia,
or as a reddened area (erythroplakia), or as a red and white
(erythroleukoplakia) mucosal change under standard white light
examination. However, these cellular changes are often non-detectable
to the human eye (even with magnification eyewear) under standard
lighting conditions. Often, when the lesion becomes visible,
it has advanced to invasive stages. The high mortality rate
is directly related to the lack of early detection of potentially
malignant lesions. When diagnosis and treatment are performed
at or before a Stage 1 carcinoma level, the survival rate
is more than 90%.
The cancers which have seen a major decline
in the mortality rate have included colon, cervical, and prostate
cancer and the primary reason is early detection and screening.
We can make a difference in the oral cancer
mortality rate.
Early screening, diagnosis, and treatment
planning saves lives.
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Risk Factors
Understanding the causative factors of cancer
will contribute to prevention of the disease. Age is frequently
named as a risk factor for oral cancer, as most of the time
it occurs in those over the age of 40. The age of diagnosed
patients may indicate a time component in the biochemical
or biophysical processes of aging cells that allows malignant
transformation, or perhaps, immune system competence diminishes
with age. However, it is likely that the accumulative damage
from other factors, such as tobacco use, are the real culprits.
It may take several decades of smoking for instance, to precipitate
the development of a cancer. Having said that, tobacco use
in all its forms is number one on the list of risk factors.
At least 75% of those diagnosed are tobacco users. When you
combine tobacco with heavy use of alcohol, your risk is significantly
increased, as the two act synergistically.Those who both smoke
and drink, have a 15 times greater risk of developing oral
cancer than others.
Tobacco and alcohol are essentially chemical
factors, but they can also be considered lifestyle factors,
since we have some control over them. Besides these, there
are physical factors such as exposure to ultraviolet radiation.
This is a causative agent in cancers of the lip, as well as
other skin cancers. Cancer of the lip is one oral cancer whose
numbers have declined in the last few decades. This is likely
due to the increased awareness of the damaging effects of
prolonged exposure to sunlight, and the use of sunscreens
for protection. Another physical factor is exposure to x-rays.
Radiographs regularly taken during examinations, and at the
dental office, are safe, but remember that radiation exposure
is accumulative over a lifetime. It has been implicated in
several head and neck cancers.
Biological factors include viruses and fungi,
which have been found in association with oral cancers. The
human papilloma virus, particularly HPV16 and 18, have been
implicated in some oral cancers. HPV is a common, sexually
transmitted virus, which infects about 40 million Americans.
There are about 80 strains of HPV, most thought to be harmless.
But 1% of those infected, have the HPV16 strain which is a
causative agent in cervical cancer, and now is linked to oral
cancer as well. There are other risk factors which have been
associated with oral cancers, but have not yet been definitively
shown to participate in their development. These include lichen
planus, an inflammatory disease of the oral soft tissues.
There are studies which indicate a diet low
in fruits and vegetables could be a risk factor, and that
conversely, one high in these foods may have a protective
value against many types of cancer.
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Signs & Symptoms
One of the real dangers of this cancer, is
that in its early stages, it can go unnoticed. It can be painless,
and little in the way of physical changes may be obvious.
The good news is however, that your dentist or doctor can
see or feel the precursor tissue changes, or the actual cancer
while it is still very small, or in its earliest stages. It
may appear as a white or red patch of tissue in the mouth,
or a small indurated ulcer which looks like a common canker
sore. Because there are so many benign tissue changes that
occur normally in your mouth, and some things as simple as
a bite on the inside of your cheek may mimic the look of a
dangerous tissue change, it is important to have any sore
or discolored area of your mouth, which does not heal within
14 days, looked at by a professional. Other symptoms include;
a lump or mass which can be felt inside the mouth or neck,
pain or difficulty in swallowing, speaking, or chewing, any
wart like masses, hoarseness which! lasts for a long time,
or any numbness in the oral/facial region. Other than the
lips, the most common areas for oral cancer to develop are
on the tongue and the floor of the mouth. Individuals that
use chewing tobacco, are likely to have them develop in the
sulcus between the lip or cheek and the soft tissue (gingiva)
covering the lower jaw (mandible). In the US, cancers of the
hard palate are uncommon, though not unknown. The base of
the tongue at the back of the mouth, and on the pillars of
the tonsils, are other sites where it is commonly found. If
your dentist or doctor decides that an area is suspicious,
the only way to know for sure is to do a biopsy of the area.
This is not painful, is inexpensive, and takes little time.
It is important to have a firm diagnosis as early as possible.
It is possible that your general dentist or medical doctor,
may refer you to a specialist to have the biopsy performed.
This is not cause for alarm, but a normal part of referring
that happens ! between doctors of different specialties.
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Early Detection
Historically, it has been difficult to determine
which abnormal tissues in the mouth are worthy of concern.
The fact is, the average person routinely has conditions existing
in their mouths that mimic the appearance of pre-cancerous
changes, and very early cancers of the soft tissues. One study
determined that the average dentist sees 3-5 patients a day
who exhibit soft tissue abnormalities, most of which are benign
in nature. Even the simplest things, such as a canker sore
(herpes simplex), the wound left by accidentally biting the
inside of your cheek, or sore spots from a poorly fitting
prosthetic appliance or denture, all at first examination,
share similarities with dangerous lesions. Some of these conditions
cause physical discomfort, others are painless. The question
is which ones deserve action, and which ones bear watching
and waiting?
There has been a tendency to watch these
areas over an extended period to determine if they are dangerous
or not. Unfortunately, this philosophy leads to a situation
in which a dangerous lesion may continue to prosper and grow
into a later stage, hard to cure cancer. Any sore, discoloration,
induration, prominent tissue, irritation, hoarseness, which
does not resolve within a two week period on its own,
with or without treatment, should be considered suspect and
worthy of further examination or referral. Besides a routine
visit to the dental office for regular examinations, it is
the patient's responsibility to be aware of changes in their
oral environment. When these changes occur, they need to be
brought to the attention of a qualified dental professional
for examination. The dental professional needs to be current
in the knowledge base necessary to make a proper diagnosis,
and be competent in the proper screening procedures to identify
oral cancer.
How to know if you have had a proper oral
cancer screening
There are two separate issues, discovery
and diagnosis. Discovery is the result of a thorough visual
and manual examination. A protocol for a comprehensive oral
cancer screening appears elsewhere in this section of the
web site. It includes a systematic visual examination of all
the soft tissues of the mouth, including manual extension
of the tongue to examine its base, a bi-manual palpation of
the floor of the mouth, and a digital examination of the borders
of the tongue, and the lymph nodes surrounding the oral cavity
and in the neck. New diagnostic aids, including lights, dyes,
and other techniques are beginning to appear on the marketplace.
While making the discovery process more effective, it is still
possible to do a comprehensive examination through a proper
visual and tactile process.
Once suspect tissues have been detected,
the only way a definitive diagnosis of oral cancer may be
made is through biopsy. Given the large number of tissue abnormalities
a dentist sees every day, it is not logical, nor practical,
that each one of these be biopsied. The first question which
may help in the determination of which abnormality bears closer
examination, is how long has the suspect condition been present?
Any condition that has existed for 14 days or more without
resolution should be considered suspect and worthy of further
diagnostic procedures or referral. Certainly, it is common
knowledge that two of the most prevalent lesions that mimic
oral cancer, are the herpes simplex ulceration, and aphthous
ulcerations, each resolving of their own accord in approximately
10-14 days. Perhaps that sentence should be underlined, since
one of the most common diagnoses received with referred patients
to a major university cancer pathology department is "an
atypical herpeti! c/aphth ous lesion" These all too frequently
turn out to be squamous cell carcinomas, which have been under
observation.... for several months.
Still, it would seem impractical at these
early timelines to engage in biopsy. A oral biopsy brush is
available that makes this decision to get an early diagnosis
through biopsy easier to make. Simple, painless, and accurate
diagnosis of soft tissue abnormalities can be obtained through
its use.
Note that this system is not designed to
provide the kind of information, specifically cellular architecture,
that would be obtained through a punch or incisional biopsy.
But it will provide an answer to the question of whether malignancy
exists or not, through a quick, minimally invasive, and inexpensive
procedure. Should positive results be returned through this
system, the brush biopsy must be followed by a conventional
biopsy procedure for confirmation. The strong argument for
the brush biopsy is that it eliminates the waiting and watching
of a suspicious lesion, while it develops from a highly treatable
and curable, early stage localized cancer, into a life threatening
late stage malignancy. Positive identification of oral cancers
at the earliest stages, result in the best prognosis for cure
and long-term survivability.
Creating awareness, discovery, diagnosis,
and referral. When it comes to oral cancer and saving lives,
these are the primary responsibilities of the dental community.
The most important step in reducing the death rate from oral
cancer is early discovery. No group has a better opportunity
to have an impact than members of the dental community.
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