Level V lymph node dissection in oral and oropharyngeal carcinoma patients with clinically node-positive neck: Is it absolutely necessary?

Objectives: Postoperative shoulder dysfunction has been significantly associated with any dissection of level V secondary to traction or with ischemic injury to the spinal accessory nerve. The aim of this study was to determine whether the dissection of level V lymph node pads is absolutely necessary in therapeutic neck dissection as a treatment for oral and oropharyngeal squamous cell carcinoma (OOSCC) patients with clinically N+ neck. Study Design: Retrospective chart review. Methods. We performed a retrospective analysis of 93 OOSCC patients who underwent surgical treatment of the primary lesion along with a simultaneous comprehensive neck dissection from January 1992 to December 2003. Of these, only one patient had a clinically positive neck node at level V. During the neck dissection, the contents of the level V lymph nodes were dissected, labeled, and processed separately from the remainder of the major neck dissection specimen. We studied the incidence of pathologic metastasis to level V lymph nodes. In addition, we also evaluated several potential risk factors for metastatic disease in the level V lymph nodes such as sex, age, T stage, N stage, histologic grade, and presence of other positive lymph nodes. Results: A total of 96 comprehensive neck dissections were performed in this series. The prevalence of metastases in the level V lymph nodes was 5% (5 of 93) in ipsilateral and 0% (0 of 3) in contralateral. necks. One case with clinically positive node at level V had a pathologic positive node in level II, III, IV, and V. Occult metastasis rate of ipsilateral level V was 4% (4 of 92). There was a statistically significant association between level V metastases and a positive N stage above N2b (P = .01). The presence of metastasis in other multiple neck levels, particularly the combined neck levels II, III, and IV, also have a statistically significant association with level V metastasis (P = .023). Conclusion. Level V lymph node pads may be preserved in modified neck dissections on OOSCC patients with clinically N+ neck below the nodal stage N2a.