Early Postoperative Adjuvant Radiotherapy Versus Active Monitoring After Gross Total Resection for Atypical Meningiomas: Factors Associated with Early Recurrence.

ABSTRACT

AIM: To investigate the predictors of recurrence after gross total resection (GTR) that require early adjuvant radiotherapy upfront rather than at initial recurrence of atypical meningiomas (AMs). MATERIAL AND METHODS: A retrospective study of gross totally resected AMs was conducted in a tertiary care center within ten years. The clinical, radiological, and pathological parameters were analyzed statistically, and the factors associated with recurrence after GTR were determined with univariate analysis. RESULTS: Among 23 AMs with GTR, 34.8% showed recurrence in a median follow-up of 40 months after the surgery. Preoperative tumor volume, tumor location in the skull base or tentorium, and lack of progesterone expression were associated with the higher recurrence rate. AMs with a preoperative volume of 27.5 cm³ were the most significant risk factor for the recurrence (a 9.3-fold increase) than those with < 27.5 cm 3 < /sup > (66.7% vs. 14.3%, respectively). CONCLUSION: Patients diagnosed with larger AMs ( > 27.5 cm 3 < /sup > ) might have higher recurrence rates after GTR and, therefore, would benefit from early adjuvant radiotherapy without waiting for a recurrence. AMs located in the skull base or tentorium and AMs having no progesterone expression might also be potential predictors for recurrence.