The Ki-67 Proliferation Index as a Marker of Time to Recurrence in Intracranial Meningioma

Abstract

<jats:title>Abstract</jats:title> <jats:sec> <jats:title>BACKGROUND</jats:title> <jats:p>There are examples of incongruence between the WHO grade and clinical course in meningioma patients. This incongruence between WHO grade and recurrence has led to search for other prognostic histological markers.</jats:p> </jats:sec> <jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>To study the correlation between the Ki-67 proliferative index (PI), risk of recurrence, and recurrence rates in meningioma patients.</jats:p> </jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>We prospectively collected pathological diagnosis of de novo consecutive meningiomas. In total, we followed 159 patients with clinical controls until recurrence, death, or emigration. We estimated the correlation between risk of recurrence and Ki-67 PI when adjusted for age at diagnosis, sex, WHO grade, extent of surgical resection, and tumor location. We estimated the cumulative incidence of recurrence when considering death without recurrence a competing risk. We report recurrence rates per 100 person-years.</jats:p> </jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>A 1%-point increase of Ki-67 PI yielded a hazard ratio of 1.12 (95% CI: 1.01-1.24) in a multivariate analysis. The cumulative incidence of recurrence was 3% for Ki-67 0% to 4% vs 19% for Ki-67 &amp;gt; 4% meningiomas after 1 yr, but 24% vs 35%, respectively, after 10 yr. There was no significant difference in mean Ki-67 PI between nonrecurrent and recurrent meningioma in a 2-sample t-test (P = .08). The strongest relationship was detected between Ki-67 PI and time to recurrence: Ki-67 &amp;lt; 4% meningiomas recurred after median 4.8 yr, compared to 0.60 to 0.75 yr for patients with higher Ki-67 PI.</jats:p> </jats:sec> <jats:sec> <jats:title>CONCLUSION</jats:title> <jats:p>Ki-67 PI was a marker for time to recurrence rather than a predictor of recurrence. Ki-67 PI may be utilized for patient tailored follow-up.</jats:p> </jats:sec>

Long-Term Follow-Up and Predictors of Functional Outcome after Surgery for Spinal Meningiomas: A Population-Based Cohort Study

“…A higher WHO grade was not associated with a difference in reoperation rate or recurrence. Generally, time to recurrence is expected to be shorter for more aggressive histological tumors following subtotal resection [38]. One explanation for our results is that we only had two cases of WHO grade II tumors, which probably limited the statistical analysis.…”

FORGE: A Novel Scoring System to Predict the MIB-1 Labeling Index in Intracranial Meningiomas

“…They identified that patients with a MIB-1 labeling index of 0% to 4%, 5% to 9%, and ≥10% had 2.4, 4.9, and 9.7 recurrences per 100 person-years, respectively. Furthermore, patients with a MIB-1 index ≥5% had significantly more often meningioma recurrences within the first 2 years after surgery compared to patients with a MIB-1 index 0% to 4% [ 58 ]. Moreover, a recent retrospective investigation of 239 WHO grade I meningiomas revealed a recurrence rate of 18.8% in patients with a GTR and a MIB-1 labeling index >4.5%, which resulted in a similar risk of recurrence as patients who underwent a subtotal resection.…”

TERT promoter mutations in primary and secondary WHO grade III meningioma

“…Malignant tumors such as WHO grade III meningiomas recur if follow-up is long enough, while time to recurrence may differ with the growth rates. In analogy, the Ki-67 proliferation index reflects time to recurrence rather than cumulative incidence of recurrence during long-term follow-up of meningiomas (15). In this context, rates of recurrence and mortality may be preferrable prognostic markers.…”