PROGNOSTIC SIGNIFICANCE OF PROLIFERATION (KI-67) AND ANGIOGENESIS (CD34) MARKERS IN MENINGIOMAS FOR THE DEVELOPMENT OF REHABILITATION STRATEGIES

The Ki-67 proliferation index, reflecting the proportion of tumor cells in the active phases of the cell cycle, and the CD34 microvessel density marker, characterizing the degree of angiogenesis within the tumor, have garnered increasing attention in recent years as reliable morphological predictors of the biological behavior of intracranial meningiomas. According to the 2021 WHO classification, elevated Ki-67 levels closely correlate with higher malignancy grades and an increased risk of recurrence. Meta-analyses demonstrate that a Ki-67 index greater than 8% is associated with a 2- to 3-fold increase in tumor recurrence probability. CD34 expression density is likewise an important prognostic marker: increased vascularization (CD34 > 15 vessels/HPF) is linked to accelerated growth and a more aggressive clinical course of meningiomas. Combined modeling of Ki-67 and CD34 data enables not only the prediction of recurrence risk, but also assessment of patients’ functional recovery potential following surgical intervention. Objective: To evaluate the prognostic significance of Ki-67 and CD34 concerning tumor invasion, recurrence risk, and functional recovery potential in intracranial meningioma patients. Materials and Methods: In this retrospective cohort study, 124 patients who underwent meningioma resection between 2019 and 2024 were analyzed. Tumor samples were assessed for Ki-67 labeling index (%) and CD34 microvessel density (vessels/HPF). Depth of brain invasion (≥ 3 mm), extent of resection (Simpson grades I-IV), 5-year recurrence status, and functional gain (ΔKPS, ΔFIM at 3 months) were recorded. Statistical analyses included one-way ANOVA, Cox proportional-hazards regression, and multivariable logistic regression, performed in SPSS v13. Results: Early recurrence: Ki-67 > 8 % (HR = 3.1; p < 0.05) and CD34 > 15 vessels/HPF (HR = 2.4; p < 0.05) were independent predictors. Rehabilitation potential: Ki-67 < 4 % (OR = 4.6; p < 0.01) and CD34 < 12 vessels/HPF (OR = 2.9; p < 0.01) predicted a high likelihood of ΔKPS ≥ 15 and ΔFIM ≥ 20. Invasion: Depth ≥ 3 mm increased recurrence risk 3.8-fold (p < 0.001). Functional outcomes: Radical resection (Simpson I-II) combined with low Ki-67/CD34 levels was associated with significantly greater ΔKPS and ΔFIM (p < 0.001). Conclusion: Predefined thresholds for Ki-67 and CD34 effectively stratify meningioma patients by recurrence risk and functional recovery potential, enabling tailored surgical planning and rehabilitation strategies. Routine inclusion of these markers in pathologic reports is recommended as part of a multidisciplinary management approach.