Oral Surgery - OPMDs Overview

Oral Surgery - Potentially Malignant Disorders of Oral Mucosa

• Potentially malignant disorders (OPMDs) are oral tissue changes that can progress to malignancy.
• Oral carcinogenesis is a multistage process with cellular and tissue changes (dysplasia).
• Some changes are reversible; others lead to invasive malignant cells if the reparative ability of the cells is surpassed.

Risk Factors

• Inherent susceptibility: Genetic predisposition, age (typically >45), ethnicity, and socioeconomic status.
• Tobacco use: Smoking and smokeless tobacco.
• Betel quid use: Betel nut, slaked lime, tobacco, and spices wrapped in betel leaf.
• Alcohol use: Alcohol consumption is also a risk factor.
• Diet and nutrition: Nutritional deficiencies, and high intake of processed meat products.
• Poor oral health and dental hygiene: Poor oral care and hygiene.
• Infective agents: Human papillomavirus (HPV) types, bacteria (candida, syphilis).
• Immunodeficiency: Congenital, HIV infection, immunosuppression, and AIDS.
• Ultraviolet irradiation: Exposure to UV radiation.

Diagnostic Method - Patient History

• Obtain a detailed patient history focusing on risk factors and medical conditions predisposing to premalignant lesions.
• Collect significant relevant information.

Diagnostic Method - Clinical Examination

• Thorough inspection of mucosal surfaces under proper lighting to identify suspicious lesions.
• Palpation with a gloved finger to determine the texture of any detected lesions.
• Carefully wipe away leukoplakic lesions using a damp swab (acute pseudomembranous candidiasis might be the cause).
• Clinicians should take and record clinical photographs.

Diagnostic Method - Investigations

• Consider blood tests and oral swabs for microbiological assessment.
• An incisional or excisional biopsy for histopathological examination.
• During incisional biopsy, select a site encompassing the lesion's most severe-looking parts, margins, and surrounding normal tissue.
• Interpretation must consider the clinical context and history to avoid misinterpretation. Oral tissues need to be assessed comprehensively for potential cancer.

Diagnostic Aids for Clinical Detection

• Vital tissue staining: Neoplastic and dysplastic tissues can take up specific dyes, allowing differentiation from normal tissues. (e.g., Toluidine blue, Lugol iodine, 5-aminolevulenic acid). Fluorescence imaging can be used for visualization.
• Light-based detection: High-accuracy tools for identifying dysplastic or neoplastic tissue.
• Brush Biopsy and Exfoliative Cytology: Analysis of cells shed from mucosal surfaces for the identification of abnormal cells.
• Salivary analysis: Analysis of salivary composition and shed oral epithelial cells.

Leukoplakia

• Most common potentially malignant lesion (60%-70%).
• A predominantly white patch or plaque of questionable risk that isn't diagnosable as another condition. This is a diagnosis of exclusion.
• High risk of malignant transformation in specific locations (lateral tongue, floor of mouth).
• Risk factors include smoking, length of leukoplakia, and patient's demographics.
• Clinical presentation can include homogeneous (uniform white) or non-homogeneous (varying appearances including speckled, warty, or nodular). Proliferative verrucous leukoplakia (PVL) is a high-risk type.
• Thickness and size of the lesion are prognostic factors.
• Other risk factors include long duration within non-smokers and female gender.
• Differential diagnoses include white sponge nevus, frictional keratosis, morsicatio buccarum, chemical injury, pseudomembranous candidiasis, leukoedema, lichen planus, lichenoid reaction, discoid lupus erythematosus, and hairy leukoplakia/skin graft.
• Diagnosis involves eliminating other potential white lesions. All leukoplakias, regardless of location or type, require biopsy to confirm if any malignant transformation has occurred.
• Different degrees of epithelial dysplasia (mild, moderate, severe, carcinoma in situ) vary in terms of severity and extent.
• Treatment varies: observation, surgical excision, cryosurgery, CO2 laser, or other nonsurgical treatments.

Erythroplakia

• Uncommon lesion (0.02% - 5.7%), red patch that cannot be diagnosed as another condition.
• High potential for malignant transformation (14%-50%).
• Frequent locations are the floor of the mouth, buccal mucosa, soft palate, and tongue.
• Characterized by thickened, smooth or velvety-textured epithelium that lacks keratin production and demonstrates underlying microvasculature and chronic inflammation.
• Histopathologically severe epithelial dysplasia, carcinoma in situ, or invasive squamous cell carcinoma are likely.
• Differential diagnoses are infections (e.g., candidiasis, histoplasmosis, bacterial), mucosal diseases (atrophic lichen planus, systemic lupus erythematosus, pemphigus, pemphigoid), vascular malformations (hamartoma, hemangioma, kaposi sarcoma), and other less likely cases.
• Diagnosis and treatment require complete excision with clear margins to rule out local recurrence.
• Management depends on the severity.

Palatal Changes Associated with Reverse Smoking

• A specific lesion related to reverse smoking that presents in red, white or mixed colors.
• Includes diagnosis, no special difficulties.
• Malignant transformation risk is 0.3%.
• Treatment involves stopping the habit, close monitoring, and possible biopsy if necessary.

Oral Submucous Fibrosis

• A chronic disorder characterized by fibrosis of the oral mucosa, seen predominantly in parts of Southeast Asia.
• Characterized by epithelial changes including hyperkeratosis, atrophy, and epithelial dysplasia or even carcinoma in a sizable percentage.
• Treatment involves a range of methods: Nutrition (vitamins, minerals), physiotherapy, intralesional injections, and surgery depending on the severity.

Actinic Cheilitis (Cheilosis)

• Thickening of the lower lip vermilion, caused by prolonged sun exposure.
• Predilection for males over 40, fair skin, old age, immunosuppression, and arsenic/HPV exposure.
• Progression may lead to chronic ulcerations often representing early squamous cell carcinoma.
• Therapy includes sunscreen use, biopsy (if any signs of dysplasia), and possible lip shave (vermilionectomy) in dysplasia cases. Alternative treatments depend on lesion characteristics.

Oral Lichen Planus and Oral Lichenoid Lesions

• Chronic mucocutaneous disease.
• Suggested to have an immune-mediated cause affecting basal cell layer.
• Predominantly seen in middle-aged adults, with women being more likely to suffer.
• Commonly involves buccal mucosa, gingiva, and tongue.
• Two significant types are reticular (characterized by Wickham striae) and erosive (irregular plaques).
• Malignant transformation rate is considered controversial, ranging widely from 0.3%–3%, most common among erosive types.
• Treatment includes corticosteroids (topical or systemic) and other supportive therapies.