MENINGIOMA-04 PATTERN OF KI67 INDEX IN RELATION TO ANATOMICAL, HISTOLOGICAL AND DEMOGRAPHIC CHARACTERISTICS AMONG PATIENTS WITH MENINGIOMA SEEN AT KENYATTA NATIONAL HOSPITAL

BACKGROUND: Meningioma remains the most frequently reported primary intracranial tumor that is indicated in the brain or spinal cord. It is relatively under-studied in Kenya, and hence literature and data are scarce on its immunohistochemically expression as well as its correlated clinical outcomes. The role of Ki-67 in the prognosis of meningioma’s has been indicated to be still debatable. METHODOLOGY: Using a cross-sectional study design, patients who presented with meningioma were recruited through consecutive sampling. Data collected age, sex and the location of the tumor. Samples archived in the laboratory after surgery were retrieved, and Ki67 testing done to assess outcomes.Data analysis: SPSS version 26 was used. The Chi-square test was used to test the association between categorical exposure variables and the occurrence of Ki67. A p-value of 0.05 was considered statistically significant. RESULTS: The study showed the average age of patients with new onset meningioma, as identified by histology, was 48.4 years. Our study found a higher percentage of female participants (79.5%) compared to male (20.5%). Meningothelial was the most common histological subtype, accounting for 34.1% of cases and classified as Grade 1 according to the WHO Grade system. 26.5% of grade 1 meningiomas had Ki67 labeling index of above 4%. The atypical type was the most significantly associated with Ki67 with a p-value of 0.012. The expression of Ki-67 labeling index was associated with WHO grade 2, and patients with this grade had a 6 times greater chance of having a Ki67 labeling index of more than 4%. The AUC model performance was 67.8%. This study found age, gender and location of tumor has no influence on mean Ki 67 labelling index. CONCLUSION: High level of Ki-67 expression is associated with high pathological WHO grade II meningioma. 26.5% of grade 1 meningiomas had high Ki67 labeling index above 4%.