Cortactin expression assessment improves patient selection for a watchful waiting strategy in pT1cN0‐staged oral squamous cell carcinomas with a tumor infiltration depth below 4 mm

BACKGROUND: In this feasibility study we aimed to evaluate the value of previously reported molecular tumor biomarkers associated with lymph node metastasis in oral squamous cell carcinoma (OSCC) to optimize neck strategy selection criteria. METHODS: The association between expression of cortactin, cyclin D1, FADD, RAB25, and S100A9 and sentinel lymph node status was evaluated in a series of 87 (cT1‐2N0) patients with OSCC treated with primary resection and SLNB procedure. RESULTS: Tumor infiltration depth and tumor pattern of invasion were independent prognostic markers for SLN status, while none of the tumor makers showed a better prognostic value to replace SLNB as neck staging technique in the total cohort. However, in the subgroup of patients with pT1N0 OSCC, cortactin expression (OR 16.0, 95%CI 2.0–127.9) was associated with SLN classification. CONCLUSIONS: Expression of cortactin is a promising immunohistochemical tumor marker to identify patients at low risk that may not benefit from SLNB or END.