Koos Boeve

124 Chapter 7 ABSTRACT Background: Compared to the elective neck dissection, sentinel lymph node biopsy (SLNB) is minor surgery. However, 70% of the patients with early stage (cT1-2N0) oral squamous cell carcinomas (OSCC) have no lymph node involvement making a SLNB an unnecessary procedure. This study aimed to evaluate reported molecular tumor biomarkers associated with lymph node metastasis, in early stage OSCC to improve neck strategy selection criteria. Material and Methods: Expression of cortactin, cyclin D1, FADD, RAB25 and S100A9 was tested on primary tumor material from a homogeneous, well-described cohort of 87 OSCC patients who underwent SLNB neck staging, and associated with lymph node status. Results: Cortactin was associated with lymph node status in patients with a pT1 tumor and infiltration depth <4 mm (OR 16.0, 95% CI 2.0-127.9) with an negative predictive value of 92%. Conclusions: Expression of cortactin is a promising tumor marker to select early stage OSCC patients for a watchful waiting strategy instead of a SLNB.