What is the initial investigation approach for a patient presenting with leukoplakia (white patch or plaque) on the tongue in the outpatient department (OPD)?

Management of Tongue Leukoplakia in the Outpatient Department

A biopsy is the essential first step in investigating a patient with leukoplakia on the tongue to rule out malignancy, with excisional biopsy being preferred over incisional biopsy whenever possible due to high rates of underdiagnosis with incisional techniques. 1, 2

Initial Assessment

History and Risk Factor Evaluation

• Obtain detailed history of tobacco and alcohol use, which are major risk factors for oral leukoplakia and subsequent malignant transformation 3
• Document duration of the lesion and any changes in size, appearance, or symptoms 3
• Assess for symptoms such as pain, burning sensation, or difficulty with speech or swallowing 3
• Document history of previous oral lesions or head and neck cancers 3

Clinical Examination

• Thoroughly examine the leukoplakia lesion, noting:
  • Size and exact location on the tongue 3
  • Morphology (homogeneous vs. non-homogeneous) - non-homogeneous lesions have significantly higher risk of malignancy 2
  • Presence of ulceration, induration, or bleeding 3
• Complete examination of the entire oral cavity and oropharynx for additional lesions 3
• Palpation of cervical lymph nodes, noting any enlargement, tenderness, or fixation 3

Diagnostic Workup

Biopsy

• Excisional biopsy is strongly recommended for tongue leukoplakia whenever feasible, particularly for:
  • Lateral tongue lesions (59.1% coexistence with malignancy) 1
  • Non-homogeneous lesions (higher risk of underdiagnosis) 2
  • Small to moderate-sized lesions that can be completely excised 1
• If incisional biopsy is necessary due to lesion size:
  • Multiple-site biopsies should be performed to reduce underdiagnosis rate (29.5% with single-site vs. 11.9% with multiple-site biopsies) 2
  • Target the most suspicious areas (areas of irregularity, erythema, or induration) 2
  • Ensure adequate depth of biopsy to avoid superficial sampling errors 1

Histopathological Assessment

• Request evaluation for:
  • Presence and degree of dysplasia (mild, moderate, severe) 1, 4
  • Evidence of invasive carcinoma 1
  • Consider special staining for CD163+ macrophages in biopsy specimens, which may help identify higher risk lesions 5

Additional Investigations

• Standard investigations:
  • Chest X-ray to rule out synchronous bronchial tumors 3
  • Orthopantomography if there is suspicion of bone involvement 3
• Optional investigations based on clinical findings:
  • CT scan or MRI of the head and neck if there is suspicion of deep muscle or bone involvement 3
  • Cervical ultrasonography if lymph node evaluation is difficult clinically 3
  • Panendoscopy if there is history of prolonged alcohol and tobacco use 3

Common Pitfalls and Caveats

• Underdiagnosis from incisional biopsy is common (73.3% for lateral tongue leukoplakia), leading to missed diagnoses of malignancy 1
• The three most common errors in diagnosis are:
  • Mis-selection of sampling site within a large area of leukoplakia 1, 2
  • Errors in pathology specimen preparation due to small specimen size 1
  • Superficial biopsy not capturing deeper tissue changes 1
• Non-homogeneous leukoplakia has significantly higher risk of malignancy and underdiagnosis (15.94 times higher odds of having undetected carcinoma) 2
• Lateral tongue location is associated with higher malignant potential compared to other oral sites 1, 4

Follow-up Management

• After biopsy and diagnosis, treatment options include:
  • Complete surgical excision with adequate margins for dysplastic lesions 1, 4
  • CO2 laser vaporization as an alternative treatment modality with 33.8% recurrence rate 4
  • Photodynamic therapy following specific protocols for selected cases 3
• Regular follow-up is essential regardless of initial histopathology, as malignant transformation can occur even in lesions without initial dysplasia 4, 6
• Patients should be counseled on risk factor modification (tobacco and alcohol cessation) 3