Expression of Ki-67 in early glottic carcinoma and its relation to oncological outcomes following CO(2) laser microsurgery

INTRODUCTION: The behavior of the laryngeal squamous cell carcinoma (LSCC) is marked by the degree of cell proliferation and differentiation. Ki-67 is regarded as a promising proliferation marker and has been correlated as a prognostic indicator. AIM: The aim of the present study is to determine the Ki-67 expression and its prognostic value in LSCC. MATERIALS AND METHODS: A total of eighty patients with early glottic carcinoma stage (Tis, T(1), T(2)) N(0) M(0) were included. After preoperative workup, surgery was performed using LUMINES 40C CO(2) laser and tumor resection was done which was sent for histopathological diagnosis and immunohistochemistry (IHC). IHC for Ki-67 expression could be done only on 65 specimens. RESULTS: All patients had microscopically confirmed squamous cell carcinoma. Forty-eight out of 65 specimens (75%) stained positive for Ki-67 and 17 (25%) stained negative. Out of total 48, 29 stained 2+, 11 stained 3+ and 8 stained 4+. No difference was found in Ki-67 expression in relation to age, sex, T stage, and histological grading. The association of Ki-67 with recurrence was found to be statistically significant. The association of Ki-67 with survival was also studied and Ki-67 positivity is associated with increased mortality rate, although it was not statistically significant. CONCLUSION: The proliferative index as measured by immunohistochemical staining of Ki-67 correlates with the tumor aggressiveness. High Ki-67 index is associated with early relapse and poor survival outcomes.