A cytohistological study of Ki-67 expression in ovarian tumors

Background and Objective: The study was conducted to evaluate the diagnostic accuracy of imprint cytology in ovarian neoplasms, and to investigate the biological significance of Ki-67 antigen expression in benign and malignant ovarian tumors and correlate it with histological type, grade, and stage of malignant tumor. Materials and Methods: A total of 50 cases including 25 prospective and 25 retrospective cases were studied. Imprint cytology was performed on 25 ovarian tumors and compared with histopathological diagnosis. Ki-67 immunohistochemistry was performed on all 50 cases. Results: On immunohistochemistry, benign tumors had a mean Ki-67 index of 3.2 ± 3.7 while malignant tumors had a mean Ki-67 index of 33.1 ± 16.7, the difference being statistically significant. Significant correlation was observed between the Ki-67 index and stage of the tumor; however, there was no correlation between the grade of differentiation and histological type of tumor with the Ki-67 index. Conclusions: In the present study, the Ki-67 index was higher in advanced stage tumors; hence a higher Ki-67 index points toward the aggressive behavior and poorer clinical outcomes.