Dissection of level IIb in squamous cell cancer of the upper aerodigestive tract: prospective study and systematic review of the literature

Abstract

Objectives. Selective neck dissection is commonly used to clear occult metastases in the N0 neck. The aim of this study is to identify the incidence of micrometastases in level IIb nodes in patients with upper aerodigestive tract squamous cell carcinoma with clinically and radiologically staged N0 necks and to perform a systematic review of the literature on the incidence of metastases in this setting. Methods. Thirty‐eight patients were selected and 50 neck dissection (ND) specimens were examined prospectively. Tissue dissected from level IIb was sent separately for histo‐pathological analysis. All the relevant literature in the English language was systematically reviewed. Results. On average, 2.9 ± 0.4 nodes (range 0–10) were harvested. One patient had a metastatic node in level IIb with extracapsular spread in the ipsilateral neck. No other positive nodes were detected. There was an incidental finding of a deposit of papillary thyroid carcinoma. Sixteen of the 50 NDs showed micrometastases at other levels, predominantly in level IIa (75%). The systematic review identified 11 papers with 704 patients suitable for inclusion. The overall incidence of metastatic disease at level IIb in the context of an N0 neck from any site is 2.3% (16/704). 3.5% (11/312) of oral cavity cancer metastasise to level IIb and none of the 244 patients with laryngeal cancer had level IIb metastatic nodes. Conclusions. Nodal metastasis is rare in the level IIb even in the presence of positive nodes in adjacent level IIa. There appears to be no advantage in performing contralateral level IIb dissection in N0 necks.