Step 1 of 14
Presentation & Risk Factors
Non-healing ulcer · pain/otalgia · loose teeth · tobacco/areca-nut/alcohol · OPMD (not HPV)
Oral cavity squamous cell carcinoma typically presents as a non-healing ulcer or lump in the tongue (most commonly the lateral border), floor of mouth, buccal mucosa, alveolus (gingiva), retromolar trigone, or hard palate — often indurated, with raised or rolled edges, and not healing after 2–3 weeks. Associated features include pain, referred otalgia, bleeding, loose teeth, ill-fitting dentures, dysphagia, a change in speech, trismus (suggesting deep or masticator-space involvement), and a neck mass from nodal metastasis.
The risk factors are dominated by tobacco (smoked and smokeless), areca nut / betel quid, and alcohol (tobacco and alcohol act synergistically), with oral potentially-malignant disorders (leukoplakia, erythroplakia, oral submucous fibrosis, proliferative verrucous leukoplakia, lichen planus) as premalignant precursors. A crucial distinction from oropharyngeal cancer is that oral cavity carcinoma is overwhelmingly carcinogen-driven, not HPV-driven — p16 positivity does not carry the favourable prognostic meaning here that it does in the tonsil and tongue base. A persistent oral lesion in an at-risk patient is cancer until biopsy says otherwise.
- Non-healing indurated ulcer/lump — tongue (lateral border), FOM, buccal, alveolus, retromolar, palate
- Pain, referred otalgia, bleeding, loose teeth, ill-fitting dentures, trismus, neck mass
- Risk — tobacco (smoked/smokeless), areca nut/betel quid, alcohol (synergistic); OPMD precursors
- Unlike oropharynx — carcinogen-driven, not HPV-driven (p16 not favourable here)
★ High-yield pearls (chapter-wide)
- A mouth ulcer that has not healed in 2–3 weeks is oral cancer until biopsy proves otherwise — non-healing, indurated, or raised-edge ulcers are biopsied, not re-treated as aphthae.
- Oral cavity carcinoma is a surgically-led disease — primary resection is the mainstay, in contrast to the organ-preservation chemoradiotherapy that leads in oropharynx and larynx.
- Unlike oropharyngeal cancer, oral cavity carcinoma is overwhelmingly tobacco-, alcohol-, and areca-nut-driven, not HPV-driven — p16 does not carry the same favourable meaning here.
- Depth of invasion is now part of T staging and is the strongest predictor of occult nodal metastasis — it, more than surface size, decides whether the clinically negative neck is electively treated.
- Elective neck dissection improves survival over watchful waiting in early node-negative oral cancer — the D'Cruz trial settled this; the cN0 neck with meaningful depth is dissected, not observed.
- Margins are measured on the fixed specimen and shrink — aim for a generous gross margin (≈1 cm) to land a clear (≥5 mm) histological margin, and use intra-operative frozen section.
- Cortical bone invasion changes the operation — no invasion allows a marginal mandibulectomy, while cortical or marrow invasion mandates a segmental resection.
- Positive margins or extranodal extension on final pathology mandate concurrent cisplatin chemoradiotherapy, not radiotherapy alone — the RTOG 9501 / EORTC 22931 high-risk features.
- Areca nut (betel quid) causes oral submucous fibrosis, a premalignant condition of trismus and a pale, stiff mucosa — it is a major driver of oral cancer in South Asia and warrants surveillance.
- Oral cancer field-cancerises — the whole mucosa is at risk, so multiple primaries, premalignant lesions, and second cancers are actively sought and followed lifelong.
Evidence base
4 sources- MOD
Ettinger KS, Ganry L, Fernandes RP · Oral Maxillofac Surg Clin North Am · 2019ReviewPMID 30454788
Comprehensive review of oral cavity cancer — presentation, surgical management, the neck, reconstruction, and rehabilitation.
- HIGH
Guha N, Warnakulasuriya S, Vlaanderen J · Int J Cancer · 2014Meta-analysisPMID 24302487
Meta-analysis establishing betel quid (with and without tobacco) as a strong risk factor for oral cancer.
- MOD
Mummudi N, Agarwal JP, Chatterjee S · Clin Oncol (R Coll Radiol) · 2019ReviewPMID 31174947
Reviews the epidemiology and burden of oral cancer in the Indian subcontinent, driven by tobacco and areca nut.
- HIGH
Lechner M, Liu J, Masterson L · Nat Rev Clin Oncol · 2022ReviewPMID 35105976
Reviews HPV-driven oropharyngeal cancer — the contrast that explains why oral cavity cancer is carcinogen-driven and p16-status differs.
Decision tree
The triage screen is the first gate. Classification routes the stable patient to one of the aetiology-keyed pathways below. Cross-cut cards capture the chapter's must-not-miss rules.