plaques of the lateral borders of the tongue that do not wipe
or rub off. 4, 7 It should be noted that while the condition has
been reported on sites other than the lateral tongue, this is
extremely rare. While the tongue lesions in our case could
reasonably mimic OHL, the presence of synchronous bilateral
lesions of the buccal mucosa is a helpful finding that should
make the clinician reconsider this diagnosis. Careful review of
the patient’s medical history and immune status can provide
more insight into the probability of OHL, or could shed some
light as to the underlying cause in a confirmed case. Cytology
or biopsy of a suspected case is useful in establishing a
diagnosis if the clinical presentation suggests OHL. In situ
hybridization for Epstein-Barr virus-encoded small RNAs
(EBER) is an adjunct study performed on biopsied tissue that
can also help confirm the presence of EBV-infected cells. If a
patient is diagnosed with OHL, but has a non-contributory
medical history, an appropriate medical work-up is indicated
to determine whether the patient is HIV-positive or
immunosuppressed. OHL itself does not require any
treatment, as it is considered a benign condition and will
resolve when the underlying cause of immunosuppression is
addressed.
Frictional Keratosis
Frictional keratosis is the presence of a thickened layer of
keratin on the surface of the oral mucosal epithelium in
reaction to chronic irritation, friction, or trauma. Frictional
keratosis is typically associated with sharp tooth structure in
constant or frequent contact with the oral mucosa. Frictional
keratosis might be considered in our case, given the presence
of broken down teeth. 1 However, it should be noted that the
location of the sharp tooth structures does not appear to
match the pattern, distribution and specific location of the
lesions in our case. This is useful in moving the differential
away from a tooth-related frictional keratosis. Frictional
keratosis is typically diagnosed based on the clinical
appearance of the lesion(s) and identification of a direct
mechanical irritant. A biopsy is generally not necessary to
diagnose frictional keratosis and the lesion should resolve
within a few weeks following removal of the irritant.
Leukoplakia (Epithelial Dysplasia)
A leukoplakia is a clinical lesion defined as an adherent white
plaque of the oral mucosa that cannot be diagnosed as
anything else. Leukoplakia can appear thin, thickened,
roughened, or verrucous, owing to the amount of epithelial
thickening (hyperplasia) and/or hyperkeratosis in the lesion.
Intraoral leukoplakia is considered a premalignant, or
potentially malignant, lesion. In fact, 0.13 to 17.5% of oral
leukoplakias will transform into malignancies. 10 It is not
possible to determine the presence of dysplasia or carcinoma
in a leukoplakia purely based on its clinical appearance,
although more severe clinical changes are more likely to be
associated with more severe histopathologic changes. Our
patient presented with white plaques of the lateral tongue.
While leukoplakia can develop anywhere in the oral cavity,
the ventrolateral tongue is a high-risk site for oral squamous
cell carcinoma, and a leukoplakia in this region should be
considered carefully. 1, 10 In addition, this patient reports a
history of smoking, which increases the risk for developing
oral epithelial dysplasia and carcinoma. 1 In our case, multiple
white lesions were identified. The presence of multiple
leukoplakia might raise a concern for a condition known as
proliferative verrucous leukoplakia (PVL). The lesions of PVL
often present as enlarging, haphazardly-distributed
leukoplakia with discrete but irregular borders and a
roughened or verrucous surface texture. 1 In the current case,
the distribution and appearance of the lesions, particularly
the bilateral symmetric distribution of the lesions and the
diffuse, non-plaque-like white lesions of the buccal mucosa,
are not strongly suggestive of PVL. Given the high risk of
malignant transformation in PVL, it is important to at least
consider the possibility of this condition. However, careful
examination of the lesions and questioning of the patient
should enable the clinician to arrive at the correct diagnosis.
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