Search

Classification of the extent of resection into gross and subtotal resection (GTR and STR) after meningioma surgery is derived from the Simpson grading. Although utilized to indicate adjuvant treatment or study inclusion, conflicting definitions of STR in terms of designation of Simpson grade III resections exist. Correlations of Simpson grading and dichotomized scales (Simpson grades I–II vs ≥ III and grade I–III vs ≥ IV) with postoperative recurrence/progression were compared using Cox regression models. Predictive values were further compared by time-dependent receiver operating curve (tdROC) analyses. In 939 patients (28% males, 72% females) harboring WHO grade I (88%) and II/III (12%) meningiomas, Simpson grade I, II, III, IV, and V resections were achieved in 29%, 48%, 11%, 11%, and <.5%, respectively. Recurrence/progression was observed in 112 individuals (12%) and correlated with Simpson grading (p =.003). The risk of recurrence/progression was increased after STR in both dichotomized scales but higher when subsuming Simpson grade ≥ IV than grade ≥ III resections (HR: 2.49, 95%CI 1.50–4.12; p <.001 vs HR: 1.67, 95%CI 1.12–2.50; p =.012). tdROC analyses showed moderate predictive values for the Simpson grading and significantly (p <.05) lower values for both dichotomized scales. AUC values differed less between the Simpson grading and the dichotomization into grade I–III vs ≥ IV than grade I–II vs ≥ III resections. Dichotomization of the extent of resection is associated with a loss of the prognostic value. The value for the prediction of progression/recurrence is higher when dichotomizing into Simpson grade I–III vs ≥ IV than into grade I–II vs ≥ III resections. [ABSTRACT FROM AUTHOR]

Risk factors for prediction of prognosis in meningiomas derivable from routine preoperative magnetic resonance imaging (pMRI) remain elusive. Correlations of tumor and edema volume, disruption of the arachnoid layer, heterogeneity of contrast enhancement, enhancement of the capsule, T2-intensity, tumor shape, and calcifications on pMRI with tumor recurrence and high-grade (WHO grade II/III) histology were analyzed in 565 patients who underwent surgery for WHO grade I (N = 516, 91%) or II/III (high-grade histology, N = 49, 9%) meningioma between 1991 and 2018. Edema volume (OR, 1.00; p = 0.003), heterogeneous contrast enhancement (OR, 3.10; p < 0.001), and an irregular shape (OR, 2.16; p = 0.015) were associated with high-grade histology. Multivariate analyses confirmed edema volume (OR, 1.00; p = 0.037) and heterogeneous contrast enhancement (OR, 2.51; p = 0.014) as risk factors for high-grade histology. Tumor volume (HR, 1.01; p = 0.045), disruption of the arachnoid layer (HR, 2.50; p = 0.003), heterogeneous contrast enhancement (HR, 2.05; p = 0.007), and an irregular tumor shape (HR, 2.57; p = 0.001) were correlated with recurrence. Multivariate analyses confirmed tumor volume (HR, 1.01; p = 0.032) and disruption of the arachnoid layer (HR, 2.44; p = 0.013) as risk factors for recurrence, independent of histology. Subgroup analyses revealed disruption of the arachnoid layer (HR, 9.41; p < 0.001) as a stronger risk factor for recurrence than high-grade histology (HR, 5.15; p = 0.001). Routine pMRI contains relevant information about the risk of recurrence or high-grade histology of meningioma patients. Loss of integrity of the arachnoid layer on MRI had a higher prognostic value than the WHO grading, and underlying histological or molecular alterations remain to be determined. [ABSTRACT FROM AUTHOR]

The World Health Organization (WHO) classification and grading system attempts to predict the clinical course of meningiomas based on morphological parameters. However, because of high interobserver variation of some criteria, more reliable prognostic markers are required. Here, we assessed the TERT promoter for mutations in the hotspot regions C228T and C250T in meningioma samples from 252 patients. Mutations were detected in 16 samples (6.4% across the cohort, 1.7%, 5.7%, and 20.0% of WHO grade I, II, and III cases, respectively). Data were analyzed by t test, Fisher's exact test, log-rank test, and Cox proportional hazard model. All statistical tests were two-sided. Within a mean follow-up time in surviving patients of 68.1 months, TERT promoter mutations were statistically significantly associated with shorter time to progression (P < .001). Median time to progression among mutant cases was 10.1 months compared with 179.0 months among wild-type cases. Our results indicate that the inclusion of molecular data (ie, analysis of TERT promoter status) into a histologically and genetically integrated classification and grading system for meningiomas increases prognostic power. Consequently, we propose to incorporate the assessment of TERT promoter status in upcoming grading schemes for meningioma. [ABSTRACT FROM AUTHOR]

Estimating the risk of recurrence after surgery remains crucial during care of patients with meningioma. Numerous studies identified correlations of characteristics on routine preoperative magnetic resonance imaging (MRI) with postoperative recurrence or high-grade histology but showed partially inconclusive results. A systematic review of the literature was performed about findings on preoperative MRI and their correlation with high-grade histology and recurrence. Quality of the included studies was analyzed using standardized Quality Assessment of Diagnostic Accuracy Studies criteria. Among the 35 studies included, quality of the series according to the Quality Assessment of Diagnostic Accuracy Studies criteria differed widely. Remarkably, MRI variables found to be associated with high-grade histology were commonly not consistently associated with prognosis and vice versa. Correlations of the tumor size, the peritumoral edema size, and contrast-enhancement of the tumor capsule with high-grade histology were controversial. In most studies, non-skull base tumor location, cyst formation, heterogenous contrast-enhancement, an irregular tumor shape, and disruption of the tumor/brain border but not intensity of the lesion on T2-weighted images, calcifications, or bone involvement were associated with grade II/III histology. Although tumor and edema size were usually found to correlate with recurrence, heterogenous contrast enhancement, cyst formation, intensity of the tumor on T2-weighted MRI, and enhancement of the tumor capsule were mostly not related with progression. Several mostly consistent but partially inconsistent variables associated with high-grade histology or prognosis were identified. Although standardized studies are needed to provide further clarification, consideration of these findings can help to improve estimation of prognosis and can therefore improve postoperative care in patients with meningioma. [ABSTRACT FROM AUTHOR]

Objective We analyzed the applicability of the Simpson grading system to estimate the risk of tumor recurrence after microsurgery for recurrent meningiomas. Methods Correlations between the Simpson grade and the extent of resection (EOR) (gross total resection [Simpson grade I and II] vs. subtotal resection [Simpson grade ≥III]) with tumor relapse after microsurgery for meningioma recurrence were investigated compared with the findings in primary diagnosed tumors. Location-specific differences were further elucidated in subgroup analyses. Results A total of 829 individuals (88% in group A) with primary diagnosed meningioma and 109 patients with first postoperative recurrence (12% in group B) who underwent surgery were included. In group A, both Simpson grade (P = 0.003) and EOR (P < 0.001) correlated strongly with recurrence. In group B, Simpson grade correlated with tumor location (P = 0.030), and the risk of subtotal resection was greater in the posterior fossa (odds ratio, 5.26; P = 0.018) and skull base (odds ratio, 6.16; P = 0.002) meningiomas. Older age at tumor relapse (hazard ratio [HR], 1.05; P = 0.001), male sex (HR, 2.19; P = 0.02), and grade 2/3 histologic findings (HR, 2.18; P = 0.02). However, neither the Simpson grade nor dichotomized EOR correlated with further tumor recurrence. The frequency of postoperative complications was similar in both groups. Conclusions Surgery for recurrent meningiomas is not generally associated with an increased risk of postoperative complications compared with resection of primary diagnosed tumors. However, the Simpson grade and EOR in recurrent meningiomas correlated poorly with further tumor relapse. The lower prognostic value of the tumor remnants left behind during microsurgery for recurrent meningiomas should be considered when operating on lesions that can be surgically challenging. Highlights • We analyzed the applicability of the Simpson grade after surgery for recurrent meningiomas. • The Simpson grade is a poor predictor of second recurrence after surgery for recurrent meningioma. • Surgery for recurrent meningioma is safe. • A retentive surgical treatment should be considered for resection of recurrent meningioma in surgical challenging locations. [ABSTRACT FROM AUTHOR]

Objective In meningioma, correlation of brain invasion with prognosis and clinical variables remains controversial. Methods Correlation of brain invasion with clinical and histopathologic variables was investigated in 467 patients with primary intracranial meningioma. Results Diffuse ( n = 3; 10%), clusterlike ( n = 11; 34%) or fingerlike ( n = 18; 56%) invasion was detected in 32 patients (7%). Brain invasion was more common in males than in females (13% vs. 5%; odds ratio, 2.75; 95% confidence interval, 1.29–5.89; P = 0.009) and pattern of invasion differed between genders ( P = 0.037). Brain invasion was absent in 401 benign meningiomas and present in 48% of 60 atypical ( n = 29) and 50% of 6 anaplastic ( n = 3) meningiomas ( P < 0.001) but was independent of tumor location and extent of resection. Progression occurred in 11% and was more frequent (31% vs. 15%; P = 0.036) in invasive than in noninvasive tumors, but only after gross total resection and in univariate analyses, and independent of invasion pattern. In atypical meningiomas, frequency of adjuvant irradiation was similar comparing invasive and noninvasive tumors and grading solely based on brain invasion ( n = 20; 33%), other World Health Organization (WHO) criteria ( n = 31; 52%) or a combination of both ( n = 9; 15%). Risk of recurrence was lower (hazard ratio, 0.258, 95% confidence interval, 0.09–0.734; P = 0.011) when grading exclusively based on brain invasion than when further WHO criteria were in addition present and the progression-free interval among the first was similar to benign tumors. Conclusions Brain invasion and its patterns are correlated to gender. In contrast to the current WHO classification, invasion was associated with recurrence only after gross total resection and not independent of further histopathologic criteria of atypia. [ABSTRACT FROM AUTHOR]