Frequency and therapeutic implications of “skip metastases” in the neck from squamous carcinoma of the oral tongue

BACKGROUND: Supraomohyoid neck dissection is an adequate operation for the elective treatment of the neck for patients with oral cavity cancer. Squamous cell carcinoma of the oral tongue, however, metastasize to clinically negative nodes in 20% to 30% of patients. These nodes usually are located in levels I-III. METHODS: The medical records of 277 previously untreated patients with squamous cell carcinoma of the oral tongue were reviewed between the years 1970 and 1990. All patients had a glossectomy and neck dissection as part of their initial treatment. Patients were evaluated as to the findings in their neck. The following group of patients were included: (1) patients who had level III nodes positive, without disease in levels I and II; (2) patients with disease in level IV; (3) patients with disease in level IIB or IIIB, and; (4) patients who were electively dissected and whose neck did not demonstrate any pathologically involved nodes, but level IV was not included in the dissection and the patient subsequently developed pathologically positive nodes in level IV. RESULTS: Of all patients, 15.8% had either level IV metastasis as the only manifestation of disease in the neck or the level III node was the only node present without disease in level I-II. CONCLUSION: The usual supraomohyoid neck dissection is inadequate for a complete pathologic evaluation of all the nodes at risk for patients with squamous carcinoma of the oral tongue. This may create a dilemma in determining whether postoperative radiotherapy is necessary. Consequently, all patients with squamous cell carcinoma of the oral tongue should have levels I-IV nodes removed if an elective neck dissection is part of their initial therapy.