The necessity of level IIb dissection for clinically negative neck oral squamous cell carcinoma

Abstract Aim: Selective neck dissection reduces the incidence of complications associated with radical neck dissection while achieving the same oncological results, especially in clinically node-negative (cN0) cases. The most common complications associated with selective neck dissection are spinal accessory nerve dysfunction and shoulder disability, which result from level IIb dissection. The aim of the present study was to evaluate the incidence of level IIb lymph node metastasis in cN0 oral squamous cell carcinoma (OSCC) patients to determine the necessity of selective neck surgery. Methods: The medical records of 138 consecutive OSCC cN0 patients seen from June 2012 to June 2017 were retrospectively reviewed for age, gender, tumor localization, and TNM classification. Results: The incidence of occult metastasis was 29.7%, but level IIb nodes were not involved in any case. Discussion: The lack of involvement of level IIb nodes in occult metastasis, and high prevalence of shoulder dysfunction caused by injury to the spinal accessory nerve during surgery, challenge the necessity of surgical IIb node clearance in cNO OSCC; this is true for all stages and especially for early T1 stage cases, when the likelihood of occult lymph node metastasis is low (15.6%).