Selective neck dissection for clinically N0 neck in laryngeal cancer: is dissection of level IIb necessary?

The most common morbidity associated with selective neck dissection (SND; II-IV) is spinal accessory nerve dysfunction and related shoulder disability. Nerve dysfunction is usually attributed to stretching of the nerve during clearance of lymph nodes lying posterior and superior to the spinal accessory nerve (level IIb). If these lymph nodes were left in place and not removed, stretching of the spinal accessory nerve during neck dissection and postoperative shoulder disability could be avoided. 113 SNDs (II-IV) performed on clinically N0 necks of patients with laryngeal carcinoma were enrolled in this prospective study. During SND, level IIb was separately removed and processed. Mean number of lymph nodes in level IIb was 6.26 (range, 0-19). In none of the 113 SND (II-IV) specimens did level IIb contain metastases, thus providing an oncological basis that leaving these lymph nodes in place is an oncologically safe approach, probably avoiding postoperative shoulder disability.