Exodontia.Info
Leukoplakia
Leukoplakia (AKA White Patch)

Definition

The term leukoplakia (Greek, “white patch”) is defined by
the
World Health Organisation as "a white plaque /
patch, firmly attached to the oral mucosa, that cannot be
rubbed off or clinically identified as another named
entity
".  It is therefore strictly a clinical label rather than a
histological diagnosis.

Leukoplakias should be biopsied, after which a more
definitive diagnosis can be assigned.  Most prove to be
benign (usually
hyperkeratosis or chronic inflammation),
however, up to 20% may exhibit histological changes
consistent with
dysplasia or carcinoma.  They should
therefore be regarded with suspicion until proven
otherwise, particularly if occurring in a high-risk site such as
the ventral or lateral tongue or floor of mouth.

The clinical appearance is extremely variable with respect
to size, shape, thickness, and homogeneity of colour.  They
are usually asymptomatic.

Ætiology

The exact ætiology remains unknown.  Tobacco, alcohol,
chronic local friction,
betel use; sanguinarine use and
Candida albicans are important predisposing factors.  
Others include
Epstein Bar Virus and Syphilis.  These
latter carry a higher risk of
malignant transformation.

Clinical Features

Occurs in approx 1% of the population; men > women

Three clinical varieties are recognised:

  1. homogeneous (common; faintly white – very thick &
    opaque)
  2. speckled (less common; non-homogenous /
    heterogenous leukoplakias has a high risk of
    malignant transformation) and
  3. verrucous (rare).
Management of Leukoplakia
Useful Websites:

New Zealand Dermatological Society (DermNZ)

Emedicine (Dermatology)

Wikipedia

Patient UK

NHS Clinical Knowledge Summaries

NHS Choices

CancerHelp UK

Bond's Book of Oral Diseases, 4th Edition

International Agency for Research on Cancer / World Health Organisation

Emedicine (Oral Medicine)

Dermatology Online Journal

Mayo Clinic

Medscape News Today


Useful Articles:

Leukoplakia - Clinician Information Sheet.  Eastman Dental Institute Oral Medicine
Clinic

Journal of Dental Education 2002.  Systematic Review of Randomized Trials for
the Treatment of Oral Leukoplakia

CA Cancer J Clin 2002.  Oral Cancer and Precancerous Lesions

Critical Reviews in Oral Biology & Medicine 2003.  Prognosis of Oral
Pre-malignant Lesions - Significance of Clinical, Histopathological & Molecular
Biological Characteristics

Oral Oncology 2005.  Long-term treatment outcome of oral pre-malignant lesions

Cochrane Review 2008.  Interventions for treating Oral Leukoplakia

MJA 2009.  Clinical Update.  Oral White Lesions - Pitfalls of Diagnosis

Head Neck 2009.  Treatment & Follow-up of Oral Dysplasia - A Systematic
Review & Meta-Analysis
Photo of an Oral Leukoplakia
Photo of a Speckled Oral Leukoplakia
Photo of a Verrucous Oral Leukoplakia
Speckled and verrucous leukoplakias have a greater risk for malignant
transformation than the
homogeneous form.  The average percentage of
malignant transformation
for leukoplakia varies between 4% and 6%.

The
buccal mucosæ, tongue, floor of the mouth, gingivæ and lower lip are the
most commonly affected sites.  However,
leukoplakias found in the soft palate
complex
, on ventro-lateral aspects of the tongue & the floor of mouth have a high
risk of
malignant transformation.

The
malignant potential depends on appearance, site & some ætiological factors.


Laboratory Tests

Histo-pathological examination.


Differential Diagnosis

The following conditions should be considered before making a diagnosis of
leukoplakia:



Treatment

  • Elimination or discontinuation of pre-disposing factors (such as tobacco or
    betel nut)
  • Surgical excision is the treatment of choice
  • Medical treatment entails the use of anti-inflammatories or anti-fungals; topical
    anti-cancer drugs or retinoid compounds.  These cause regression of the
    leukoplakias but their efficacy is temporary.
  • Chemo-prevention, which prevents leukoplakias from becoming malignant,
    entail the use of retinoids (such as 13-cis-retinoic acid and fenretinide).  
    However, problems with side-effects, lack of availability and recurrence limits
    their use.
  • Lesions removed followed by regular follow-ups.
Last Updated 17th October 2013