Nuclear expression of p65 (RelA) in patients receiving post-operative radiotherapy for locally advanced squamous cell carcinoma of the head and neck

Background: This study investigated the prognostic role of nuclear expression of p65 in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN) receiving post-operative radio(chemo)therapy. Methods: Nuclear p65-expression (H-score ≤50 versus >50) plus twelve characteristics were analyzed in 151 patients for overall survival (OS), metastases-free survival (MFS) and loco-regional control (LRC). Additional characteristics included age, gender, Karnofsky performance score (KPS), pre-radiotherapy hemoglobin levels, tumor site, histological grading, human papilloma virus (HPV)-status, T-classification, N-classification, American Joint Committee on Cancer (AJCC)-stage, extent of resection and concurrent chemotherapy. Univariate analyses were performed with Kaplan-Meier method and log-rank test, multivariate analyses with Cox proportional hazards model. Results: On univariate analyses, p65-expression had a significant impact on OS (p < 0.001) and LRC (p < 0.001) but not on MFS (p = 0.29). On multivariate analysis, KPS ≥80 (risk ratio [RR] 2.23; p = 0.012), HPV-positivity (RR 5.83; p = 0.020), T1-T2 (RR 1.38; p = 0.048), N0-N2a (RR 2.72; p = 0.005) and complete resection (RR 2.02; p = 0.049) were positively associated with OS; p65-negativity achieved borderline significance (RR 3.02; p = 0.052). Better MFS was associated with KPS ≥80 (RR 2.49; p = 0.015), T1-T2 (RR: 1.74; p = 0.005), N0-N2a (RR: 6.22; p < 0.001) and complete resection (RR 3.43; p = 0.003). Positive associations with LRC were found for p65-negativity (RR 5.06; p = 0.008), T1-T2 (RR: 1.49; p = 0.022), N0-N2a (RR: 2.97; p = 0.004) and favorable tumor site (RR 1.28; p = 0.025). Conclusions: P65-negativity was significantly associated with improved LRC and achieved borderline significance with respect to improved OS. Thus, p65-expression may be an additional target for novel agents in the treatment of locally advanced SCCHN.