Tumor Grade and Immunohistochemical Expression for Predicting Nodal Disease in Early‐Staged Oral Squamous Cell Carcinomas

Abstract

Objectives: 1) Categorize oral squamous cell carcinoma (OSCC) patients according to nodal status at and after surgery. 2) Determine demographics, clinicopathological and histological factors contributing to nodal disease. 3) Investigate biomarkers to predict nodal status. Methods: Using the BC Cancer Registry Database, 303 primary OSCC patients who received primary curative surgical treatment from 2003 to 2007 with at least 5 years of follow-up were identified. Patients were categorized based on nodal status at and after surgery. Demographics, clinico-pathological details, treatment modalities and time to outcomes were collected and compared among groups. Immunohistochemistry (IHC) was performed on a pilot tissue microarray (n = 21) for p16, cyclin D1 (CD-1), Ki-67, p53, and pRB. Results: Patients with nodal diseases (n = 303) at the time of surgery or during the FU has a pivotal impact on the 5-year survival rates (P < 0.0001). Cox proportional hazard models identified usage of adjuvant radiotherapy and presence of nodal disease as significant predictors for poor survival (hazard ratio [HR]: 6.53, 95% confidence interval [CI], 2.86-14.91, P < 0.0001; 2.43, 95%CI, 1.18-5.02, P = 0.02, respectively). Among the 205 N0-at-surgery, one in four of them developed nodal disease and with 76% at the first 18 months post-surgery. Among those markers examined, nuclear CD-1 expression is a negative predictor for nodal disease (100% vs. 58%, P < 0.05). Conclusions: The data strongly support aggressiveness of neck metastasis either at-time-of surgery or during follow-up. Effective pathological or IHC markers to predict nodal disease pre-surgery can benefit high-risk patients receiving early intervention and avoid unnecessary ND for the low-risk patients.