Predictors of recurrence after surgical resection of parafalcine and parasagittal meningiomas.

PURPOSE: Owing to their vicinity near the superior sagittal sinus, parasagittal and parafalcine meningiomas are challenging tumors to surgically resect. In this study, we investigate key factors that portend increased risk of recurrence after surgery. METHODS: This is a retrospective study of patients who underwent resection of parasagittal and parafalcine meningiomas at our institution between 2012 and 2018. Relevant clinical, radiographic, and histopathological variables were selected for analysis as predictors of tumor recurrence. RESULTS: A total of 110 consecutive subjects (mean age: 59.4 ± 15.2 years, 67.3% female) with 74 parasagittal and 36 parafalcine meningiomas (92 WHO grade 1, 18 WHO grade 2/3), are included in the study. A total of 37 patients (33.6%) exhibited recurrence with median follow-up of 42 months (IQR: 10-71). In the overall cohort, parasagittal meningiomas exhibited shorter progression-free survival compared to parafalcine meningiomas (Kaplan-Meier log-rank p = 0.045). On univariate analysis, predictors of recurrence include WHO grade 2/3 vs. grade 1 tumors (p < 0.001), higher Ki-67 indices (p < 0.001), partial (p = 0.04) or complete sinus invasion (p < 0.001), and subtotal resection (p < 0.001). Multivariable Cox regression analysis revealed high-grade meningiomas (HR: 3.62, 95% CI: 1.60-8.22; p = 0.002), complete sinus invasion (HR: 3.00, 95% CI: 1.16-7.79; p = 0.024), and subtotal resection (HR: 3.10, 95% CI: 1.38-6.96; p = 0.006) as independent factors that portend shorter time to recurrence. CONCLUSION: This study identifies several pertinent factors that confer increased risk of recurrence after resection of parasagittal and parafalcine meningiomas, which can be used to devise appropriate surgical strategy to achieve improved patient outcomes.

Classification of Peritumoral Veins in Convexity and Parasagittal Meningiomas and Its Significance in Preventing Cerebral Venous Infarction.

OBJECTIVE: The medium (2-4 cm) convexity located closer to the sinus and parasagittal meningiomas (Sindou type I-Ⅲ) without obvious invasion of the superior sagittal sinus are considered simple to operate on. However, the tumors are often accompanied by the cortical bridging vein. Because of lack of collateral vein circulation in cortical areas, the damage of peritumoral veins will subsequently lead to venous infarction. To avoid the serious complications caused by intraoperative injury of peritumoral veins, it is necessary to define the classification of the progression of peritumoral veins and tumors to guide surgical safety. METHODS: The clinical information of 57 patients with convexity and parasagittal meningiomas was collected and retrospectively analyzed. All patients underwent preoperative magnetic resonance imaging and magnetic resonance venography scanning to observe the imaging characteristics of peritumoral veins and preoperative evaluation. The actual relationship between the tumor and peritumoral vein was observed intraoperatively. Postoperative computed tomography and magnetic resonance imaging were used to determine tumor resection and the presence of venous infarction. RESULTS: According to preoperative magnetic resonance venography and intraoperative findings, we divided the peritumoral veins into 3 types: type A (n = 33, 57.9%), the vein surrounds the tumor; type B (n = 15, 26.3%), the vein is located on the ventral side of the tumor; and type C (n = 9, 15.8%), the vein is located on the dorsal side of the tumor. Peritumoral vein injury occurred in 6 cases followed by serious complications. Treatments were as follows: 4 cases underwent decompression and 2 cases were treated conservatively. The prognosis Glasgow Outcome Scale (GOS) scores were as follows: 3 cases were score 5 for injury of posterior frontal vein or middle frontal vein, 2 cases were score 3 for injury of the central vein, 1 case was score 1 for death due to injury of the central vein. All cases were followed up for 6 months. CONCLUSIONS: Attention should be paid to the peritumoral vein of special meningiomas. Injured vein in the medial third of superior sagittal sinus carries a high rate of postoperative morbidity. Understanding the type of peritumoral veins preoperatively can be used as a guide in determining the corresponding protective strategy during surgery, which can significantly decrease postoperative disability and improve quality of life.