AtlasWhiteLeukoplakia

White Lesions

Leukoplakia

aka Oral leukoplakia · OL

Predominantly white lesion of oral mucosa that cannot be characterised as any other definable lesion. A potentially malignant disorder.

Prevalence
≈ 2% globally
MT rate
≈ 1%/year (up to 70% for PVL)
High-risk sites
Floor of mouth, ventral tongue
Diagnosis
Clinical + histological (exclusion)
Treatment
Habit cessation + excision

Red Flags

  • ·Induration
  • ·Ulceration or bleeding
  • ·Rapid increase in size
  • ·Speckled or nodular appearance
  • ·Cervical lymphadenopathy
  • ·Floor of mouth or ventral tongue location

Clinical Tips

  • ·Any leukoplakia that fails to regress in 2–4 weeks after removing irritants must be biopsied
  • ·Sample the reddest, most indurated area — not the whitest
  • ·Photograph at every visit for objective comparison

Examination Checklist

  • ·Inspect all mucosal surfaces including floor of mouth and ventral tongue
  • ·Palpate lesion for induration
  • ·Photograph and measure
  • ·Document habit history
  • ·Plan biopsy site (most suspicious area)

§ figuresFigures (3)

Fig. 1Photo taken of patient, who will remain anonymous, treated at the University of Tennessee Health Science Center: College of Dentistry in Memphis, Tennessee. The lesion is an example of leukoplakia. Biopsy was going to be

“Leukoplakia02-04-06” · Photo uploaded by: dozenist. · CC BY-SA 3.0 · Wikimedia Commons

Fig. 2These images are part of the 2013 publication from the NIH "Detecting Oral Cancer: A Guide for Health Care Professionals". Available on the 15/7/14 at https://www.nidcr.nih.gov/oralhealth/topics/oralcancer/detectingoralc

“NIH DOC 17 Leukoplakia” · BodyParts3D/Anatomography · Public domain · Wikimedia Commons

Fig. 3Title Leukoplakia Description Gum damage caused by leukoplakia (with white patches shown). Leukoplakia are patches on the tongue, in the mouth, or on the inside of the cheek that occur in response to long-term irritation

“Leukoplakia” · Unknown photographer · Public domain · Wikimedia Commons

Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Leukoplakia figures pending faculty review.

§ overviewOverview

WHO 2005: 'A white plaque of questionable risk having excluded other known diseases or disorders that carry no increased risk for cancer.'

§ icdICD Classification

ICD-10 K13.21

§ etiologyEtiology

  • 01Tobacco (smoking and smokeless)
  • 02Areca nut / pan / gutka
  • 03Alcohol (synergistic)
  • 04Candida albicans (co-factor in nodular type)
  • 05HPV 16/18 (subset)
  • 06Chronic mechanical / galvanic irritation (contested)
  • 07Idiopathic (~10–30%)

§ riskRisk Factors

  • 01Male, age > 40
  • 02Heavy tobacco or areca use
  • 03Immunosuppression
  • 04Prior head-and-neck malignancy
  • 05Nutritional deficiency (Fe, folate, vit A/B12)

§ geneticsGenetics & Molecular Biology

  • 01Loss of heterozygosity at 3p, 9p21 (CDKN2A), 17p (TP53) predicts progression
  • 02Aneuploidy on DNA image cytometry — strong risk marker
  • 03TP53 mutation in dysplastic epithelium

§ epidemiologyEpidemiology

Global point prevalence ≈ 2% (range 0.5–3.5%); South Asia up to 5–10%. Male:female ≈ 2:1. Peak 50–70 y. Malignant transformation rate ≈ 1% per year overall.

§ pathogenesisPathogenesis

Chronic exposure of basal keratinocytes to carcinogens (tobacco nitrosamines, areca alkaloids) → oxidative DNA damage → clonal expansion of altered keratinocytes with hyperkeratosis and progressive dysplasia. Field cancerisation explains multifocal disease and PVL.

§ clinicalClinical Features

  • 01Homogeneous — thin, flat, uniform white plaque with sharp margins
  • 02Non-homogeneous — nodular, verrucous, speckled (erythroleukoplakia) — significantly higher malignant risk
  • 03Proliferative verrucous leukoplakia (PVL) — multifocal, persistent, recurrent, elderly women, gingiva
  • 04Cannot be scraped off (differentiates from candidiasis)
  • 05Common sites: buccal mucosa, lateral/ventral tongue, floor of mouth, retromolar area

§ signsSigns & Symptoms

  • 01Usually asymptomatic — discovered on routine exam
  • 02Roughness or altered taste
  • 03Pain, induration or bleeding suggest malignant change

§ differentialDifferential Diagnosis

  • 01Frictional keratosis
  • 02Lichen planus (reticular)
  • 03White sponge nevus
  • 04Pseudomembranous candidiasis
  • 05Leukoedema
  • 06Nicotinic stomatitis
  • 07Hairy leukoplakia (EBV, HIV)

§ criteriaDiagnostic Criteria

  • 01Diagnosis of exclusion — clinically white plaque not attributable to another known disease
  • 02Biopsy from most suspicious (red, nodular, indurated) area is mandatory to grade dysplasia

§ histopathHistopathology

  • 01Hyperkeratosis (ortho- or para-) ± acanthosis
  • 02Epithelial dysplasia graded mild / moderate / severe / carcinoma in situ (WHO 2022 — low vs high grade binary system now preferred)
  • 03Dysplastic features: basal cell hyperplasia, drop-shaped rete ridges, nuclear pleomorphism, hyperchromatism, increased/abnormal mitoses, individual cell keratinisation, loss of polarity
  • 04Basement membrane intact — distinguishes from invasive SCC
  • 05PVL: verrucous surface, minimal dysplasia early, progressive verrucous or squamous cell carcinoma

§ investigationsInvestigations

  • 01Toluidine blue vital staining (adjunct, false positives)
  • 02Autofluorescence (VELscope) screening
  • 03Brush cytology + DNA image cytometry
  • 04Incisional biopsy of most suspicious area — GOLD STANDARD
  • 05Molecular markers: LOH panel, TP53 IHC in research settings

§ ihcIHC / Special Stains

  • 01p53 — suprabasal / diffuse staining suggests dysplasia
  • 02Ki-67 — suprabasal proliferation indicates dysplasia
  • 03Podoplanin — over-expression associated with progression

§ whoWHO Classification

WHO 2022 Head & Neck Tumours: classified under Oral Potentially Malignant Disorders (OPMDs). Dysplasia grading recommended as two-tier (low-grade / high-grade) alongside traditional three-tier system.

§ classificationClassification

  • 01Homogeneous
  • 02Non-homogeneous: nodular, verrucous, speckled (erythroleukoplakia)
  • 03Proliferative Verrucous Leukoplakia (PVL)
  • 04By site: idiopathic vs tobacco-associated

§ planTreatment Planning

  • 01Confirm diagnosis histologically
  • 02Assess dysplasia grade and size
  • 03Stop all habits before definitive therapy
  • 04Multidisciplinary review for PVL and severe dysplasia

§ treatmentTreatment

  • 01Habit cessation (tobacco, areca, alcohol) — MANDATORY first step
  • 02Small homogeneous, no dysplasia: observation + 3-monthly review
  • 03Dysplastic or non-homogeneous: complete excision
  • 04Topical/systemic retinoids, β-carotene, lycopene — adjuncts only, high recurrence on withdrawal

§ medicalMedical Management

  • 01Vitamin A / retinoids (13-cis retinoic acid) — reduces size, does not prevent transformation
  • 02β-carotene, lycopene supplementation
  • 03Topical bleomycin (severe dysplasia, off-label)

§ surgicalSurgical Management

  • 01Cold-knife excision with 5 mm margin for dysplastic lesions
  • 02CO2 laser ablation / excision — good haemostasis, minimal scarring, but no specimen if ablation
  • 03Cryosurgery — limited use
  • 04Photodynamic therapy (5-ALA) for large field lesions

§ complicationsComplications

  • 01Malignant transformation to SCC
  • 02Recurrence after excision (10–35%)
  • 03Post-surgical scarring, restricted mouth opening
  • 04Missed dysplasia if inadequate biopsy site

§ recurrenceRecurrence Rate

10–35% after surgical excision; higher for PVL (up to 70%). Lifelong surveillance required.

§ followupFollow-up Protocol

  • 013-monthly for first year
  • 026-monthly for years 2–5
  • 03Annually thereafter, lifelong for PVL / high-grade dysplasia
  • 04Re-biopsy any change in colour, texture, symptoms

§ prognosisPrognosis

Overall malignant transformation ≈ 1% per year (range 0.1–17%). Risk factors: non-homogeneous type, size > 200 mm², floor of mouth / ventral tongue, high-grade dysplasia, female non-smoker, PVL (up to 70% lifetime).

§ preventionPrevention

  • 01Tobacco and areca cessation counselling
  • 02Alcohol moderation
  • 03Regular oral cancer screening in high-risk groups
  • 04Public health education, ban on smokeless tobacco

§ examKey Examination Points

  • 01Site, size, colour (uniform vs mixed), surface (smooth, nodular, verrucous)
  • 02Consistency and induration
  • 03Wipes off? (excludes candidiasis)
  • 04Cervical lymphadenopathy
  • 05Habit history duration and frequency

§ revisionQuick Revision Summary

  • 01Diagnosis of exclusion — clinical + histological
  • 02Non-homogeneous >> homogeneous risk
  • 03Habit cessation is treatment step 1
  • 04Biopsy is mandatory
  • 05Lifelong follow-up for high-risk lesions

§ vivaBDS Viva Questions

  • 01Define leukoplakia per WHO 2005.
  • 02Which type has the highest malignant transformation rate?
  • 03How do you biopsy a large heterogeneous leukoplakia?
  • 04What is PVL and why is it dangerous?
  • 05Name three histological features of epithelial dysplasia.
  • 06How does leukoplakia differ from candidiasis clinically?
  • 07What are the WHO 2022 changes to dysplasia grading?
  • 08Enumerate treatment options.
  • 09What is field cancerisation?
  • 10Name molecular markers predicting transformation.

§ bdsBDS Professional Examination

  • 01Define leukoplakia. Classify and describe clinical features, histopathology and management of oral leukoplakia (10 marks).
  • 02Short note: Proliferative verrucous leukoplakia.

§ fcpsFCPS Residency Questions

  • 01Discuss the concept of oral potentially malignant disorders, molecular basis of malignant transformation in leukoplakia, and evidence for chemoprevention.
  • 02Critically evaluate CO2 laser vs cold-knife excision for dysplastic leukoplakia.

§ pearlsClinical Pearls

  • 01Any leukoplakia that fails to regress 2–4 weeks after removing irritants must be biopsied.
  • 02Red > white — a speckled lesion is more ominous than a homogeneous plaque.
  • 03PVL is a clinical, not histological, diagnosis — established retrospectively.

§ mnemonicsMnemonics

  • 01Non-homogeneous = Nasty (higher risk)
  • 02PVL — Persistent, Verrucous, Lethal

§ readingSuggested Reading

  • 01Warnakulasuriya S. Oral potentially malignant disorders. Oral Oncol 2020.
  • 02van der Waal I. Oral leukoplakia — a proposal for uniform reporting. Oral Oncol 2000.
  • 03WHO Head & Neck Tumours 5e (2022).

§ differentialDifferential Comparison

EntityFeatureDistinguisher
Frictional keratosisTrauma-relatedResolves in 2–4 weeks after removing irritant
Lichen planusReticular Wickham striaeBilateral symmetrical, band-like lymphocytic infiltrate
Candidiasis (pseudomembranous)White curdy plaqueWipes off, KOH shows hyphae
White sponge nevusBilateral spongy folds since childhoodAutosomal dominant, keratin 4/13 mutation

§ mcqsMCQs — Assessment (8)

Question 1

Highest malignant transformation is seen in:

Question 2

Leukoplakia is defined as:

Question 3

The best biopsy site in a heterogeneous leukoplakia is:

Question 4

Basement membrane integrity is:

Question 5

PVL classically affects:

Question 6

First step in management of leukoplakia is:

Question 7

WHO 2022 recommends dysplasia grading as:

Question 8

Which is NOT a feature of epithelial dysplasia?

References

  1. Neville BW et al. Oral & Maxillofacial Pathology, 4e
  2. Warnakulasuriya S, Kujan O et al. J Oral Pathol Med 2021 — nomenclature and classification of OPMDs
  3. WHO Classification of Head and Neck Tumours, 5e (2022)

Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.