Oral Cavity Lesions & Mucosal Disease
Wipe it, time it, and biopsy what won't go away
White and red lesions
The wipe test. The first question for any white lesion is whether it scrapes off. Candidiasis wipes away; leukoplakia, hairy leukoplakia, and lichen planus do not.
| Lesion | Appearance | Association | Action |
|---|---|---|---|
| Candidiasis | Creamy curds that wipe off to a red base | Inhaled steroids, antibiotics, dentures, diabetes, HIV | Clotrimazole or miconazole buccal (nystatin alternative); fluconazole if severe or esophageal |
| Leukoplakia | Fixed white plaque | Tobacco, alcohol; premalignant | Biopsy; stop tobacco; excise dysplasia |
| Erythroplakia | Velvety red patch | Highest malignant potential | Always biopsy |
| Hairy leukoplakia | Corrugated white plaques, lateral tongue | EBV; HIV or other immunosuppression | HIV testing; improves with ART |
| Lichen planus | Bilateral lacy buccal striae | T-cell mediated; hepatitis C | Topical steroids; test for HCV |
Leukoplakia and erythroplakia. Leukoplakia is a clinical label for a white plaque that cannot be wiped off or explained by another diagnosis. It is premalignant; dysplasia is most likely on the floor of the mouth and ventrolateral tongue and in speckled (red-and-white) lesions, so persistent plaques are biopsied, tobacco is stopped, and dysplasia is excised. Erythroplakia is rarer but far more dangerous: most biopsies show severe dysplasia, carcinoma in situ, or invasive SCC.
Candidiasis. Besides classic thrush, Candida causes atrophic red patches, denture stomatitis, and angular cheilitis; chemotherapy and infancy are further risks. KOH shows budding yeast and pseudohyphae, though diagnosis is usually clinical. Mild thrush responds to clotrimazole troches or miconazole buccal tablets (IDSA preferred), with nystatin swish-and-swallow as a less effective alternative; moderate–severe disease, or odynophagia signaling esophageal involvement, needs oral fluconazole. Inhaled-steroid users should rinse and spit after each dose and use a spacer, and unexplained thrush in an adult prompts a glucose check and HIV testing. In infants, nystatin is given and a breastfeeding mother's nipples are treated to prevent reinfection.
Hairy leukoplakia and lichen planus. Oral hairy leukoplakia is painless, results from EBV replication, and is not premalignant; its importance is what it reveals, namely HIV or other immunosuppression such as transplant drugs or steroids. Oral lichen planus produces lacy white Wickham striae on both buccal mucosae; the erosive form is painful and carries a small SCC risk, so those lesions are followed.
Ulcers and vesicles
Recurrent aphthous ulcers. These are round, shallow, painful ulcers with a yellow-gray base and red halo on nonkeratinized mucosa (buccal and labial mucosa, ventral tongue). Minor aphthae heal in 1–2 weeks without scarring; topical corticosteroids such as triamcinolone paste and topical anesthetics relieve symptoms. Severe or frequent ulcers prompt a search for Behçet disease, inflammatory bowel disease, celiac disease, HIV, and B12, folate, or iron deficiency.
Behçet disease: recurrent oral aphthae plus genital ulcers, uveitis, and skin lesions such as erythema nodosum or pathergy (a sterile pustule at a needle prick); linked to HLA-B51 and Silk Road ancestry.
| Feature | Primary HSV gingivostomatitis | Herpangina |
|---|---|---|
| Agent | HSV-1; ages about 6 months–5 years | Coxsackie A; summer and fall |
| Location | Gums, tongue, lips, perioral skin | Soft palate, uvula, tonsillar pillars |
| Gingiva | Swollen, red, bleeding | Spared |
| Treatment | Early oral acyclovir (ideally within 72 hours), hydration, analgesia | Supportive; self-limited |
Primary herpetic gingivostomatitis. High fever, drooling, and refusal to drink accompany vesicles that rupture into ulcers, so dehydration is the main danger. Later reactivations usually appear as herpes labialis on the lip border.
Benign lumps and jaw necrosis
Tori. Torus palatinus (midline hard palate) and torus mandibularis (lingual mandible) are bony-hard exostoses under normal mucosa; they need no treatment unless they interfere with dentures.
Mucocele and ranula. A mucocele is a bluish, fluctuant cyst, usually on the lower lip, formed when lip biting ruptures a minor salivary duct; it is excised with its feeding gland. A ranula is the floor-of-mouth equivalent arising from the sublingual gland; a plunging ranula dissects through the mylohyoid into the neck, and removing the sublingual gland prevents recurrence.
Medication-related osteonecrosis of the jaw. Exposed or probeable jawbone for more than 8 weeks in a patient on bisphosphonates, denosumab, or antiangiogenic drugs, without prior jaw radiation, defines MRONJ. Risk is highest with high-dose IV therapy for cancer and after dental extraction, so dental work is completed before treatment starts. Management is chlorhexidine rinses, antibiotics for infection, and debridement of necrotic bone. Exposed bone in a previously irradiated field is osteoradionecrosis instead.
When to biopsy
The rule. Any oral ulcer, white or red patch, or mass that persists more than 2–3 weeks after irritants (sharp teeth, ill-fitting dentures) are removed is biopsied to exclude squamous cell carcinoma. Oral SCC is driven by smoked and smokeless tobacco, alcohol, and betel quid; it favors the lateral and ventral tongue and floor of the mouth and often appears as a painless, indurated ulcer. HPV-driven SCC arises mainly in the oropharynx (tonsils, base of tongue).