Pathology · patient case with 6 questions
White and Pigmented Oral Lesions
demo: 58-year-old male
chief: Routine examination; several mucosal findings noted.
history: Smokes one pack per day for 30 years. Occasional alcohol.
meds: None
findings: Finding 1: a small white plaque on the soft palate that does not wipe off. Finding 2: a white plaque on the lateral tongue border, 3 mm, non-wiping. Finding 3: a flat blue-grey macule in the buccal mucosa adjacent to a large amalgam restoration. Finding 4: irregular erythematous patches with white serpiginous borders on the dorsal tongue that shift location between visits. Finding 5: a bony hard midline swelling of the hard palate.
Question 1
For the white plaque on the soft palate that does not wipe off, all of the following belong in the differential EXCEPT:
Show answer and explanation
Correct answer: A. Pleomorphic adenoma
- A. Correct — this is the exception. Pleomorphic adenoma is a benign salivary gland tumor presenting as a firm submucosal mass of normal mucosal color, not a surface white plaque.
- B. Lichen planus produces white striae or plaques on the mucosa and belongs in the differential.
- C. Nicotinic stomatitis produces a diffusely white, fissured palate with red-dotted inflamed minor salivary duct openings in a heavy smoker.
- D. Leukoplakia is by definition a white patch that cannot be wiped off and cannot be attributed to any other disease — exactly this presentation.
Question 2
What is the appropriate first step for the 3 mm white lesion on the lateral tongue border in this smoker?
Show answer and explanation
Correct answer: C. Biopsy, because the lateral tongue is the highest-risk site for squamous cell carcinoma
- A. Empiric antifungal therapy delays diagnosis of a lesion that does not resemble candidiasis — it would wipe off if it did.
- B. Steroids may mask a dysplastic or malignant lesion and are not appropriate before diagnosis.
- C. Correct. The lateral border and ventral surface of the tongue, along with the floor of mouth, are the highest-risk intraoral sites. In a heavy smoker, a persistent non-wiping white lesion there warrants biopsy.
- D. A trial of irritant removal is reasonable when a mechanical cause is evident; here the risk profile and site argue for definitive tissue diagnosis.
Question 3
The flat blue-grey macule adjacent to the amalgam restoration is best characterized as:
Show answer and explanation
Correct answer: A. A smooth, non-exophytic lesion consistent with amalgam tattoo
- A. Correct. An amalgam tattoo is flat, smooth, and non-exophytic, with no surface change; radiographs may show radiopaque particles. It requires no treatment when the clinical picture is typical.
- B. Ulceration with rolled borders is a malignancy pattern and is not a feature of amalgam tattoo.
- C. Exophytic growth would raise concern for melanoma or nevus and would change the management.
- D. Amalgam particles do not blanch under pressure, which helps distinguish them from vascular lesions.
Question 4
The migratory erythematous patches with serpiginous white borders on the dorsal tongue represent:
Show answer and explanation
Correct answer: D. Geographic tongue (benign migratory glossitis)
- A. Hairy leukoplakia is a corrugated white lesion of the lateral tongue in immunosuppressed patients, EBV-driven and non-migratory.
- B. Median rhomboid glossitis is a fixed, well-demarcated depapillated rhomboid area anterior to the circumvallate papillae, associated with Candida.
- C. Erythroplakia is a fixed velvety red patch with high malignant potential — it does not migrate.
- D. Correct. Loss of filiform papillae in irregular zones with raised white serpiginous margins that change location over days to weeks is diagnostic of geographic tongue. It is benign; reassurance suffices.
Question 5
The bony hard midline swelling of the hard palate is best identified radiographically as:
Show answer and explanation
Correct answer: C. Torus palatinus, appearing as a well-defined midline radiopacity
- A. Ossifying fibroma is a well-circumscribed intrabony lesion with mixed density, typically in the posterior mandible.
- B. A nasopalatine duct cyst is a radiolucent heart-shaped lesion between the roots of the maxillary central incisors, not a bony hard surface swelling.
- C. Correct. Torus palatinus is a developmental exostosis of the midline hard palate — bony hard, covered by normal mucosa, and seen as a well-defined radiopacity superimposed on an occlusal film. No treatment is needed unless it interferes with a prosthesis.
- D. A compound odontoma is a collection of tooth-like structures within bone, not a surface exostosis.
Question 6
A separate patient has reticular white striae bilaterally on the buccal mucosa. Biopsy shows Civatte bodies and a band-like lymphocytic infiltrate. What is the first-line treatment for the symptomatic form?
Show answer and explanation
Correct answer: C. Topical clobetasol propionate
- A. Nystatin treats candidiasis, which may be superimposed on steroid therapy but is not the primary disease.
- B. Acyclovir treats herpetic infection; lichen planus is a T-cell mediated autoimmune condition, a type IV hypersensitivity reaction.
- C. Correct. Civatte bodies (apoptotic basal keratinocytes) with a band-like T-lymphocyte infiltrate is lichen planus. High-potency topical corticosteroid — clobetasol — is first line for the erosive, symptomatic form.
- D. Excision is neither practical nor curative for a bilateral, chronic, immune-mediated mucosal disease.