Predicting the probability of meningioma recurrence based on the quantity of peritumoral brain edema on computerized tomography scanning

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>The goal of this study was to determine whether the quantity of peritumoral brain edema displayed on computerized tomography (CT) scanning could be correlated with brain invasion and subsequent recurrence of meningiomas.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>One hundred thirty-five patients who underwent resection of intracranial meningiomas at the Ottawa Civic Hospital were followed during the period 1980 to 1998. A complete resection was defined as one in which tumor, invaded bone, and involved dura were removed. Tumors were examined microscopically for evidence of brain invasion. The mean follow-up period was 9 years (± 4 years, standard deviation [SD]) and the mean time to recurrence was 5 years (± 4 years, SD). The authors used a simple grading system based on the average thickness (in centimeters) of edema seen on an axial CT slice showing the most tumor. Edema grade was linearly related to edema volume determined by digitizing the scans (r = 0.96; 29 cases). The chance of brain invasion increased by 20% for each centimeter of edema (r<jats:sub>s</jats:sub> = 1, p &lt; 0.0001; 124 cases). The presence of brain invasion was predictive of recurrence after complete resection with an accuracy of 83%, a sensitivity of 89%, and a specificity of 82%. The chance of recurrence within 10 years after complete resection was given by the equation: percentage chance of recurrence = (centimeter of edema)<jats:sup>3</jats:sup> X 0.7, which can be used to predict the chance of recurrence based on findings on CT scans (r<jats:sub>s</jats:sub> = 1.00, p &lt; 0.0001; 86 patients). Statistical significance was confirmed using Kaplan-Meier and univariate and multivariate analyses. Completeness of resection was the most powerful predictor of recurrence (p &lt; 0.00001, r = 0.6), followed by edema grade and brain invasion (both p = 0.02, r = 0.1). Patient age and gender and tumor location, size, and histological subtype were nonsignificant factors.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Brain invasion causes peritumoral edema. Invaded brain tissue is also the source of residual cells in cases of tumor recurrence after gross-total resection.</jats:p></jats:sec>

Multivariate Analysis of Recurrence in Meningioma

“…Of the 83 patients in the study, a 5-year recurrence rate for benign meningiomas was 3.1%, but 45.5% and 85.7% 5-year recurrence rates were seen following a typical and malignant meningiomas, respectively. The recurrence rate rise with the histological grade rising, consistent with the findings of Ayerbe [6] et al Mantle et al [1] reported the meningiomas' cell would invade brain tissue along cell, forming bridges between cortex and surface of tumor, so they thought the invasive cell was the main reason for tumor recurrence. We suggested, for the typical and malignant meningiomas, Simpson Grade 0 or Grade I resection should be taken, if it is possible, and adjuvant radiation therapy is necessary.…”

“…Knowing extent of resection affects recurrence, some neurosurgeons mention Simpson Grade 0 resection. Simpson Grade 0, which means gross total resection of tumor, abnormal bone, and dural located within 2 cm of the bound of meningiomas [1,2] . But the Simpson Grade 0 resection is limited to cerebral convexity meningiomas, for it is hard to do it because of meningiomas' location.…”

“…The meningiomas were obviously encephalo-infiltrated, with unclear brain-tumor interface and obvious edema around tumor. Seen on the CT scans or MR images, which had higher recurrence rate, study had been had on relationship among the classified edema around tumor, opportunity to invade, and the recurrence, the result showed the edema had a linear relation to brain invasion [1] .…”

Immunohistochemical expression of Ets-1 transcription factor and the urokinase-type plasminogen activator is correlated with the malignant and invasive potential in meningiomas

“…However, paradoxically, benign meningiomas, which typically have a broad base of attachment to the dura mater, frequently indent and occasionally invade into the brain. 30 Because these invasive cells contribute to the failure of complete tumor resection, 6,30 studies aimed at the elucidation of the molecular mechanisms that regulate the invasion process in meningiomas are highly imperative. Tumor cell invasion is a complex multistep process that involves cell attachment, the proteolysis of extracellular matrix, and cellular migration.…”

Meningiomas: Updating Basic Science, Management, and Outcome

“…Indistinct borders, mushroomlike projections from the tumor, invasion deep into the brain, patchy enhancement, absence of calcification, necrosis, and marked edema may favor a diagnosis of malignant meningioma but neither CT nor MRI is diagnostic. 22,27,[32][33][34][35] The Histopathological Classification of Meningiomas has been Evolving Since 1938…”