Background: The purpose of this study was to determine the role of lymph node micrometastasis in oral and oropharyngeal cancers.
Methods: We investigated the presence of micrometastases by cytokeratin immunohistochemical staining in 54 patients with node-negative oral and oropharyngeal carcinomas.
Results: The positive rate of cytokeratin expression was 13.0% (7 of 54 patients). The incidence of micrometastasis was significantly higher in patients with more invasive tumors (p < .001) and larger tumor size (p = .034). The 5-year disease-specific (DS) survival rate significantly correlated with micrometastasis, margin involvement, and depth of invasion in the univariate analyses. Multivariate Cox regression analysis confirmed a significant association between the 5-year DS survival rate and micrometastasis (hazard ratio [HR] = 7.89; 95% confidence interval [CI] = 1.09-57.14; p = .041) and margin involvement (HR = 11.68; 95% CI = 1.22-111.75; p = .033).
Conclusion: Micrometastasis was significantly correlated with the depth of invasion and tumor size in oral and oropharyngeal cancers. Furthermore, micrometastasis was associated with adverse outcomes. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1777-E1782, 2016.
Keywords: neoplasm invasiveness; neoplasm micrometastasis; oral neoplasms; oropharyngeal neoplasms; prognosis.
© 2015 Wiley Periodicals, Inc.