Prospective study of 583 neck dissections in oral cancers: implications for clinical practice.

Background: Determining the level of nodal metastases may help decrease the extent of neck dissections and reduce morbidity.

Methods: A prospective study of neck dissections in patients with oral cancer was conducted. Each nodal level was delineated, sent for histopathology, and reported level-wise. Incidence of overall and isolated metastatic nodes at different levels was calculated. Logistic regression was used to find factors predicting metastases to levels IIB and V.

Results: Five hundred eighty-three neck dissections were prospectively evaluated. A total of 95.7% metastases occurred at levels I to IV. Overall incidence of metastases to levels IIB and V was 3.8% and 3.3%, respectively. Multivariate analysis revealed IIA positivity as an independent predictive factor for metastases to both IIB and V.

Conclusion: This study of lymph node mapping in patients with oral cancer showed a predictable pattern of lymph node metastasis according to primary site. Selective neck dissection (levels I-IV) in patients with oral cancers may be adequate. Determining status of level IIA is important to guide dissection of levels IIB and V.