Early Tongue Cancer With a Clinically Negative Neck: When to Dissect
52-year-old man presents with a 2.5 cm ulcer on the left lateral border of the tongue that has been painful for 6 weeks. Incisional biopsy shows moderately differentiated squamous cell carcinoma. He smokes one pack per day and drinks alcohol socially. Examination reveals no cervical lymphadenopathy; CT of the neck shows no enlarged or necrotic nodes. MRI reports depth of invasion of 5 mm and no bone invasion. He has no prior head and neck cancer or radiation. The tumor is mobile and does not cross the midline. He asks whether he can avoid a neck dissection because the scan is negative. He is otherwise healthy and works as a bank clerk. He is concerned about speech and swallowing after surgery. He has no trismus. His dentition is poor.
1. What operation would you recommend for the primary tumor and margins?
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I would perform wide local excision with a 1–1.5 cm mucosal margin and take frozen sections from the specimen margins; adequacy is confirmed only when margins are clear. Because the tumor is 5 mm deep, I would include underlying muscle and ensure three-dimensional clearance. Reconstruction should be planned to preserve tongue mobility; primary closure or a local flap may be adequate for a 2.5 cm defect, but a free flap is considered if the defect is larger or if speech and swallowing would be compromised. I would not use laser alone without margin control for this invasive tumor. A preoperative dental and nutrition assessment is appropriate.
2. How would you manage the clinically N0 neck, and why?
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With depth of invasion of 5 mm, the risk of occult cervical metastasis is high enough that I would recommend elective ipsilateral selective neck dissection of levels I–III, even though imaging is cN0. The scan cannot exclude micrometastasis. Sentinel lymph node biopsy is an alternative at centers with validated protocols, but it is not standard for a 5 mm invasive tongue cancer in many practices. Observation would be reasonable only for superficial tumors (eg, ≤3–4 mm) with no adverse features. The neck dissection also provides staging information that may determine adjuvant therapy.
3. What pathologic findings would trigger adjuvant radiotherapy or chemoradiation?
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Adjuvant radiotherapy is indicated for close or positive margins, perineural invasion, lymphovascular invasion, multiple positive nodes, or extranodal extension. If margins are positive or extranodal extension is present, I would add concurrent cisplatin to radiotherapy. A single positive node without extranodal extension may be treated with radiotherapy alone depending on other features. I would review the final pathology before deciding. Because he is a smoker, I would also discuss smoking cessation and monitor for second primaries.