A Non-Homogeneous Plaque on the Lateral Tongue After a Failed Antifungal Trial
A 58-year-old woman is referred by her family doctor about a white patch on the right side of her tongue that has been present for about ten weeks. She has smoked 20 cigarettes a day for 30 years and drinks vodka two or three evenings a week. The area is occasionally sore with spicy food but causes no other symptoms. Two weeks before referral her pharmacist supplied a nystatin suspension, which she used four times daily as directed, with no change.
Examination: a 2.4 by 1.5 cm non-homogeneous plaque on the right lateral border of the tongue extending towards the posterior third. The anterior part is white and striated; the posterior part is red and velvety, and this red area feels firmer than the surrounding mucosa and appears fixed to the underlying tissue. There is no ulceration, no cervical lymphadenopathy and no other mucosal lesion. The dentition is heavily restored, with sharp cusps on 46 and 47 and a fractured distolingual cusp on 47. She has no history of previous oral lesions and takes only amlodipine.
1. Give your differential diagnosis and explain why a further antifungal trial is not appropriate here. Which clinical features raise your suspicion of malignancy?
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Differential diagnosis
- Oral leukoplakia - a diagnosis of exclusion, applied only after other causes are excluded.
- Oral lichen planus - usually bilateral and reticular; a unilateral red-and-white plaque on the tongue is atypical.
- Chronic hyperplastic candidosis - usually commissural, palatal or on a denture-bearing area, and responds to antifungal treatment.
- Frictional keratosis - requires an identifiable source; the sharp cusps are ipsilateral lower molars, not in contact with the lateral tongue border, so friction is a poor explanation.
- Tobacco or alcohol-related keratosis, and tobacco pouch keratosis (site is wrong; that is usually vestibular).
- Squamous cell carcinoma or high-grade dysplasia - the key exclusion.
Why not another antifungal trial The lesion has already failed a correctly used two-week nystatin course. More importantly, a unilateral, non-homogeneous (red and white) plaque on the lateral tongue - the highest-risk intraoral site - that is firm and fixed does not warrant a therapeutic trial. A further two weeks buys nothing and delays cancer diagnosis. Antifungal trials are defensible only when the picture strongly suggests candidosis (bilateral, removable white coating, commissural or denture-related) and the lesion is not suspicious.
Risk features present Lateral tongue; non-homogeneous erythroleukoplakia; induration; fixation to underlying tissue; size over 2 cm; duration over 2 weeks; heavy smoker; regular alcohol. Induration and fixation in particular suggest invasive disease.
2. What type of biopsy would you arrange, how would you choose the site, and what else must be done before the patient leaves the clinic?
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Incisional biopsy, not excisional. The lesion is 2.4 cm on a high-risk site with mixed clinical features. A representative sample of the most suspicious area is needed; excisional biopsy of a possible carcinoma would compromise later definitive surgery and margins. Excisional biopsy is reserved for small, homogeneous lesions that can be removed whole with a margin.
Site selection. Sample the red, velvety, indurated posterior part and include the interface with clinically normal tissue. Take an adequately deep specimen including epithelium and underlying connective tissue; a superficial bite that only samples keratin is a common and avoidable error. The biopsy should be done by, or under the direct supervision of, an oral and maxillofacial surgeon.
Referral. Mark the referral as suspected oral malignancy and use the urgent two-week pathway if one exists. State the site, size, duration, risk factors and that an antifungal trial failed. Photograph the lesion with a ruler in frame for later comparison.
Before she leaves
- Smooth the sharp cusp on 47; it takes minutes and removes any frictional co-factor.
- Give smoking-cessation advice now, and record that it was given.
- Explain what the biopsy involves, that it does not spread the lesion, and the small risks of bleeding, discomfort and a suture.
- Do not start antifungals or antibiotics while she is waiting for the result.
3. How would you explain the situation to the patient, and how would you manage the result if histology showed dysplasia rather than invasive carcinoma?
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What to say. 'This is an area we cannot diagnose by looking at it. It has features that need checking under a microscope. Most such patches are not cancer, but we treat them as urgent and take a small sample. It will be examined by a specialist within about two weeks and we will see you with the result.' Add that the biopsy does not make the lesion worse or spread it, and describe the aftercare.
If dysplasia is reported
- Discuss at a multidisciplinary team meeting rather than acting alone.
- Mild to moderate dysplasia is usually excised or laser-ablated with clear margins, with continued smoking cessation, and review every 3–6 months for at least five years. The whole upper aerodigestive mucosa is field-changed, so new lesions are a real risk and lifelong surveillance is justified.
- Severe dysplasia or carcinoma in situ is treated surgically, essentially as for early carcinoma.
- If invasive squamous cell carcinoma is found, staging (imaging, neck assessment) and urgent referral to the head and neck MDT follow.
Safety netting. She must return immediately if the area becomes ulcerated or bleeds, grows, or if a neck lump appears. Document the advice, arrange the follow-up appointment before she leaves, and send a copy of the correspondence to her family doctor so the loop is closed.