Sentinel node in head and neck cancer: use of size criterion to upstage the no neck in head and neck squamous cell carcinoma.
Anatomical imaging tools demonstrate poor sensitivity in head and neck squamous cell carcinoma (HNSCC) patients with clinically node-negative necks (cN0). This study evaluates nodal size as a staging criterion for detection of cervical metastases, utilizing sentinel node biopsy (SNB) and additional pathology (step-serial sectioning, SSS; and immunohistochemistry, IHC). Sixty-five patients with clinically N0 disease underwent SNB, with a mean of 2.4 nodes excised per patient. Nodes were fixed in formalin, bisected, and measured in 3 axes before hematoxylin-eosin staining. Negative nodes were subjected to SSS and IHC. SNB-positive patients underwent modified radical neck dissection. Maximum diameter was larger in levels II and III (13.1 and 13.2 mm) when compared with level I (10.5 mm; p = .004, p = .018), while minimum diameter was constant. Positive nodes were larger than negative nodes (p = .007), but nodes found positive by SSS/IHC were not significantly larger than negative nodes for either measurement (p = .433). Sensitivity and specificity were poor for all measurements. Nodal size is an inaccurate predictor of nodal metastases and should not be regarded as an accurate means of staging the clinically N0 neck.