PREDICTIVE VALUE OF HIGH Ki-67 EXPRESSION IN STAGE I ORAL SQUAMOUS CELL CARCINOMA SPECIMENS AFTER PRIMARY SURGERY

Background. Until now prognostic evaluation for patients with oral squamous cell carcinoma (OSCC) remains difficult. Thus, the aim of the present study was to ascertain the value of Ki-67 expression in predicting locoregional recurrence in OSCC. Methods. In a large, homogeneous study population consisting of 166 patients with OSCC exclusively treated with primary surgery, expression of Ki-67 was investigated by immunohistochemistry. Results. We report that high proliferation significantly correlated to a higher risk of locoregional recurrence in stage I OSCC patients (p = .029). Carcinomas with a Ki-67 labeling index above the median showed a mean time to recurrence of 42 months, whereas mean time to recurrence was 55 months for those tumors below the median (p = .017). Conclusions. This study provides the evidence of a predictive value of Ki-67 expression in stage I OSCC. Therefore, Ki-67 expression level could be used to identify a subgroup of surgically treated patients with stage I OSCC who might benefit from treatment intensification. (C) 2010 Wiley Periodicals, Inc. Head Neck 33: 668-672, 2011