Oncology · Head and Neck Cancer
The facts most likely to be tested
Squamous cell carcinoma is the most common histological subtype of oral cavity cancer.
Tobacco use and alcohol consumption act synergistically as the primary risk factors for the development of oral squamous cell carcinoma.
Human papillomavirus (HPV), specifically high-risk strains like HPV-16, is the leading cause of oropharyngeal squamous cell carcinoma involving the tonsils and base of the tongue.
A persistent, non-healing ulcer with indurated borders or a leukoplakia (white patch) or erythroplakia (red patch) that cannot be scraped off requires an urgent incisional biopsy.
Oral cancer frequently presents as a painless mass or ulceration that may cause referred otalgia due to involvement of the glossopharyngeal nerve (CN IX).
Panendoscopy (triple endoscopy) is the gold standard for evaluating the extent of disease and identifying synchronous primary tumors in the aerodigestive tract.
Surgical resection with wide margins is the primary treatment modality for early-stage oral cavity cancer, often supplemented by adjuvant radiation or chemoradiation for advanced disease.
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A 58-year-old male with a 40-pack-year smoking history presents to the clinic complaining of a persistent sore on the left side of his tongue for 3 months. He also reports intermittent left-sided ear pain. Physical examination reveals a 2-cm ulcerated lesion with indurated, rolled borders on the lateral aspect of the tongue. There is no palpable cervical lymphadenopathy.
What is the most appropriate next step in the management of this patient?
Incisional biopsy
The patient presents with a classic non-healing ulcer with indurated borders, which is highly suspicious for squamous cell carcinoma; an incisional biopsy is required to establish a definitive tissue diagnosis.
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Etiology / Epidemiology
Predominantly Squamous Cell Carcinoma (SCC) in males >50. Primary risk factors are tobacco use and alcohol consumption.
Clinical Manifestations
Presents as a non-healing ulcer or erythroplakia. Indurated margins are the pathognomonic physical exam finding.
Diagnosis
The biopsy is the gold standard. Imaging via CT/MRI is required for staging.
Treatment
Primary treatment is surgical resection. Avoid radiation monotherapy for advanced disease.
Prognosis
Overall 5-year survival is ~60%. Lymph node metastasis is the most significant prognostic factor.
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Epidemiology & Etiology
Oral SCC accounts for >90% of oral malignancies. Strong synergistic effect between tobacco and alcohol significantly increases risk. Increasing incidence of HPV-16 associated oropharyngeal cancers in younger, non-smoking populations.
Pertinent Anatomy
The tongue (lateral border) and floor of the mouth are the most common sites for primary lesions. Rich lymphatic drainage to the cervical lymph nodes explains the high rate of regional metastasis.
Pathophysiology
Chronic irritation leads to epithelial dysplasia, progressing to carcinoma in situ and eventually invasive SCC. Molecular drivers often include p53 mutations and overexpression of EGFR. The process typically evolves from a precursor lesion like leukoplakia or erythroplakia.
Clinical Manifestations
Classic presentation is a painless, non-healing ulcer lasting >3 weeks. Look for indurated margins and fixed, firm cervical lymphadenopathy. Red flags include unexplained tooth mobility, persistent dysphagia, or a palpable neck mass.
Diagnosis
Definitive diagnosis requires an incisional biopsy of the lesion. CT or MRI of the head and neck is mandatory to assess depth of invasion and nodal involvement. PET/CT is utilized to rule out distant metastasis in advanced stages.
Treatment
Early-stage disease is managed with surgical resection with wide margins. Advanced disease requires multimodal therapy including surgery, adjuvant radiation, or cisplatin-based chemotherapy. Contraindications for surgery include unresectable carotid artery involvement or distant metastasis.
Prognosis
Prognosis is heavily dependent on TNM staging. Lymph node metastasis reduces survival by 50%. Patients require lifelong surveillance for second primary tumors due to the field cancerization effect.
Differential Diagnosis
Oral Candidiasis: wipes off with tongue depressor
Aphthous Ulcer: painful, recurrent, heals within 2 weeks
Herpes Simplex: vesicular, painful, acute onset
Syphilitic Chancre: painless, indurated, resolves spontaneously
Lichen Planus: Wickham striae, reticular pattern