Oral Cancer - Oral Screening
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Why Screen?
The stage that OSCC is diagnosed has a bearing on the
outcome of OSCC; oro-pharyngeal cancers have relatively
‘silent’ symptoms which may not be present during the
early stages of the disease, which is possibly why the
stage of disease at diagnosis has not altered in the last 40
years despite public education.
For this reason, there is an interest in the early
identification of OSCC yet the case for formal screening
programmes does not meet the criteria established by the
UK Screening Committee.
The Cochrane review on oral screening for OSCC found
that overall there is not enough evidence to decide whether
screening by visual inspection reduces the death rate for
oral cancer and there is no evidence for other screening
methods.
A GDP can expect to see at least a couple of mouth
cancer lesions during their practising lifetime. Obviously,
this is an average statistic affected by geographical
location and social class of clientèle, much like the
statistics for caries (tooth decay).
Nevertheless, to miss such a diagnosis could have a
significant effect upon a patient’s health, quality and
longevity of life and, of course, might leave the clinician
open to criticism by the patient, and possibly give rise to
medico-legal concerns.
One of the main problems with oral screening is limited
accessibility to the dental office.
High risk groups are those less likely to have access to an
NHS dentist and therefore less likely to have regular dental
appointments.
These patients, many of whom are elderly, are less likely
to schedule regular visits to the dentist due to financial
constraints, a lack of adequate facilities or indifference
towards their oral health.
Oral Cancer Screening
For oral cancer, where large numbers of patients are
already seeing a dentist, an 'opportunistic screening'
approach is generally advocated.
'Opportunistic screening' is less systematic but very much
more cost-effective than population screening. If an
opportunistic screening strategy is to be successful, all
dentists should carry out the necessary soft tissue
examination alongside hard tissue examinations.
Screening for oral cancer and pre-cancer becomes part of
the routine examination. In practice, this will normally be at
the beginning of each new course of treatment.
ViziLite®
ViziLite® is an oral cancer screening tool that may help the clinician more easily
visualise suspicious lesions. It is not a diagnostic tool.
In the UK, it is sold by Panadent. Checking their website, there seems to be a
patchy take up over England; seemingly most of the GDP practices are based in
Essex. Possibly not to be sensationalist, not many of practices using this system,
advertise their oral cancer screening facility.
Kit contents:
• Chemi-luminescent device
• 30 ml acetic acid
• Light stick holder / retractor
Last Updated 2nd March 2012
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ViziLite® Procedure. Steps:
1. Patient rinses with 1% acetic acid for 1 minute
2. Chemi-luminescent device activated & placed in ‘light stick’ holder.
3. Dim room lighting
4. Visually inspect oral cavity using device
5. Record any findings and refer the patient if necessary
How ViziLite® Works
Normal epithelium (skin) absorbs the light and appears dark; abnormal tissue
reflects light and appears bright white. Based upon the current suggested usage
for these devices, it is unclear what added benefit they would provide to the
practicing clinician.

Toluidine Blue
- Meta-chromatic dye
- Stains nuclear DNA
- 1% aqueous solution followed by 1% acetic acid to de-colourise the oral lesion
- ‘Abnormal’ tissue retains the blue dye
Tolonium chloride or toluidine blue, is a stain that like Vizilite, is used as a
screening device to help the clinician more easily visualise suspicious lesions.
Overall, toluidine blue appears to be good at detecting carcinomata but is positive
in only ~50% of lesions with dysplasia. In addition, it also frequently stains
common, benign conditions such as non-specific ulcers.
A systematic review concluded that there is no evidence that toluidine blue is
effective as a screening test in a primary care setting.
The high rate of false positive stains and the low specificity in staining dysplasia
likely outweigh the potential benefits of any additional cancers detected at this time.

OralCDx® Brush Biopsy
- Computer-assisted analysis of oral brush biopsy
- Evaluate benign appearing lesions
- High accuracy
- Does not replace scalpel biopsy
Henry Schein is the sole UK distributor for the oral
lesion brush biopsy, Oral CDx, though checking their
website I can’t find it.
This allows GDP’s to evaluate white or red lesions or
those lesions that have been identified using toluidine
blue. It’s a step up from just screening. The lesions are
brushed until they bleed and the collected cells are sent
to a lab for diagnosis.
It accurately detects pre-cancerous and cancerous
lesions
Recipient of “Seal of Acceptance” of the American
Dental Association.
That well known purveyor of fact, the Daily Mail, says
the test (& results) retail for £80.


All 3 layers (basal, intermediate and superficial layers) of epithelium are included /
needed in the brush biopsy.
OralCDx® results come back as negative (no cellular abnormalities), positive
(definitive cellular evidence of epithelial dysplasia or carcinoma) or atypical
(abnormal epithelial changes warranting further investigation).
Negative lesions require the same careful clinical follow-up as negative
histologically sampled lesions. Atypical and positive lesions require scalpel biopsy
and histology analysis.
A report is sent with results for any specimens with atypical or positive findings.
The report contains histological slides of the specimen and the oral pathologist's
report.
Disadvantages:
Often used inappropriately by the dentist. For example, some use it on
papillomata.
Cells are seen out of context, which can result in misinterpretation. For example, if
the Brush Test is used to collect cells from a patient who has lichen planus and the
cells are spread out on a slide, they will be out of context and will be read as
atypical.
There were plans by the Cancer Reform Strategy (CRS), Head, Neck and Thyroid
Cancers 2012 - Vision Paper, that by 2012, a pilot scheme should have been held
in > 1 'spearhead PCT' to assess the effectiveness of opportunistic visual oral
screening. This might include:
- setting up of a dedicated Head & Neck Clinic every 3 - 4 months to which over-
50's in high risk groups are invited
- links to specialists in secondary care, for example, sending digital photos for
advice prior to a decision to refer although there are concerns about the
feasibility of producing good enough quality photos
- posters in pharmacies offering mouth checks for ulcers
Also, action should have been taken with the manufacturers of products designed
for self-medication of oral ulcers and related conditions for the medication carton to
carry a clear health warning about oral cancer. This will need to be managed
carefully to avoid large numbers of the “worried well” overwhelming services.
Finally, the CRS opined that due to the problems of 'dental capacity' (which are
outside the scope of the CRS to resolve), it may not be feasible to focus
opportunistic screening with dentists. As a response to this perceived lack of
capacity, it was thought that GP's and practice nurses (who often see high risk
groups for other issues such as high blood pressure) and pharmacists (who are
often consulted about mouth ulcers) might be able to take up the slack.
Training issues and financial incentives would need to be considered as would the
advantages / disadvantages of screening being carried out by non-medical
personnel
Opportunistic Oral Cancer Screening
This was published by the BDA in 2000.
This is quite comprehensive. It covers:
- Oral cancer screening - obligations and opportunities
- Risk factors
- Talking to patients about oral cancer
- Administration
- Examining the head, neck and soft tissue
- Using tolonium chloride
- Putting screening into practice
If you were considering offering this type of screening service, it is well worth
looking at.
It can be downloaded from here.
Oral Cancer Screening 'Visual Aids'
To augment the GDP’s visual check of the mouth, there are a number of 'aids' to
flag up suspicious areas.
These include:
- ViziLite & MicroLux DL
- Tolonium chloride (Toluidine Blue)
- OralCDx® brush biopsy
- Exfoliative cytology
Toluidine blue has been used for a number of years. ViziLite & OralCDx® are
quite new. Exfoliative cytology is included for the sake of completeness but I don’t
believe many GDP practices do this. This tends to be done in hospitals.
Most studies show that the various aids can help but when used for screening,
economically, it is too expensive for the number of lesions correctly picked up.
VELscope, OralCDx® and Toluidine Blue staining have high false positive rates
when they are used to screen routinely for oral cancer.
It would be inefficient to allocate scarce healthcare resources to the routine use of
these devices for oral cancer screening.
These devices may be beneficial in opportunistic screening programmes or in
cancer referral clinics when the pre-test probability of oral cancer is likely to be
above 10%.
Further research is needed to determine at which pre-test probabilities, these
adjunctive diagnostic devices would be cost-beneficial for the screening of oral
cancer.

