Recurrence pattern of surgically-resected skull base versus superficial meningiomas, signs of divergent pattern

Abstract

Background: To identify differences in the recurrence pattern of surgically-resected skull base meningiomas compared with superficial intra-cranial meningiomas Methods: A retrospective hospital-based study of all patients referred to our institution from 1990 to 2014 for surgical resection of meningiomas was conducted (both primary and recurrent cases). Survival analysis was performed using IBM SPSS v22.0. Results: Overal, 398 intra-cranial meningiomas –129 (32%) skull base - were reviewed. Skull base tumors had a lower MIB-1 index (p = 0.001) and were more likely to be WHO I (p = 0.003). Meningiomas in all locations demonstrated a recurrence rate of 30% at 100 months of follow-up. Afterwards, the recurrence of skull base meningiomas plateaued (longest follow-up: 250 months) whereas superficial lesions had a recurrence rate of 80% at 230 months (p = 0.02). In multivariable analysis, patients with a first-time diagnosis (p = 0.02), those with WHO I or II tumors (p= 0.02 and 0.05), and those with a total resection (p < 0.01) were less likely to experience a recurrence. Conclusions: Skull base meningiomas are less aggressive than superficial lesions and may not need to be followed beyond 100 months. The WHO grade, complete resection, and prior recurrence are predictive factors of recurrence.