Post-operative progress of arm abduction function and rate of lymph node metastasis around the region of the accessory nerve: a multicentre prospective observational study

In patients classified as cN0, the metastatic rate of Levels IIB and V was low. Omitting Level V dissection may be an optional in strategy aimed at maintaining arm abduction function. Objective Although neck dissection is an essential technique in the surgical treatment of head and neck carcinoma, arm abduction disorders occurring after neck dissection reduce the patient's quality of life. Methods We prospectively evaluated the rate of lymph node metastasis in Levels IIB and V in head and neck cancer patients who underwent neck dissection at eight centres in Japan. In addition, post-operative arm abduction disability was classified according to functional assessment values at 1 month post-operatively, and the rate of maintained function at 6 and 12 months was evaluated. Results Lymph node metastasis occurred in Level IIB in 12 of 242 cases (4.9%) and in Level V in 5 cases (2.1%) during the 12-month post-operative course. In patients with preservation of the ipsilateral accessory nerve, arm abduction function was maintained in 142 of 209 patients (67.9%) at 12 months after surgery. Post-operative radiotherapy and Level V dissection had no statistically significant effect on the recovery of arm abduction function. Level V dissection caused a temporary loss of abduction function post-operatively. A higher arm abduction test score at 1 month post-operatively was associated with a higher rate of subsequent ability to maintain arm abduction function. Conclusions In patients classified as cN0, metastatic rate at Levels IIB and V was low. In this cohort, omitting Level V dissection may be an option in strategies aimed at maintaining arm abduction function.