Cystic Meningiomas: Correlation between Radiologic and Histopathologic Features

Sclerosing meningioma with a large peritumoral cyst: Case report

Meningioma morphology is diverse. Although unlisted in the WHO classification, sclerosing meningioma is a rare variation featuring an extremely low signal intensity on MRI T2-weighted imaging. About 50 cases of sclerosing meningiomas, including spinal tumors, have been reported; however, cases with an accompanying large peritumoral cyst remain unreported. Here, we first report a rare case of sclerosing meningioma with a large peritumoral cyst and review relevant literature.

Rare clinical entity of cystic meningioma in an elderly patient: A case report and review of the literature

INTRODUCTION AND IMPORTANCE

Meningiomas, the most prevalent extra-axial neoplasm, are frequent tumors of the central nervous system that make up around 15 % of all intracranial malignancies. Although atypical and malignant meningiomas do exist, benign meningiomas make up the majority of cases. On both computed tomography and magnetic resonance imaging, a well-circumscribed, homogeneously enhancing, extra-axial mass is a typical imaging feature. An associated cyst is a rare imaging characteristic that may make it challenging to differentiate the tumor from a primary intra-axial glial neoplasm. Peritumoral edema can also lead to false positive results.

CASE PRESENTATION

A 64-year-old female patient presented to the emergency department of our hospital due to difficulty of the speech with a 3-week duration associated with unilateral headache, gait unsteadiness, and urinary incomitance. Neuroimaging of the brain by magnetic resonance imaging (MRI) with and without gadolinium contrast revealed an extra-axial cystic lesion located in the left fronto-temporal area, measuring about 4 cm × 4 cm × 4 cm. The patient underwent a craniotomy for removal of the lesion and the resected tissue was sent to pathology. Histopathological assessment revealed a pure cystic meningioma.

CLINICAL DISCUSSION

Cystic meningioma's preoperative diagnosis is not often easy to make. Compared to CT screening, brain MRI with gadolinium offers a higher diagnostic yield. To confirm the category and subtype of the tumor, a histopathological assessment of the tumor cells should always be performed.

CONCLUSION

Although its rare, cystic meningioma should be considered in the differential diagnosis of cystic brain lesions.

Lesion delineation framework for vestibular schwannoma, meningioma and brain metastasis for gamma knife radiosurgery using stereotactic magnetic resonance images

BACKGROUND AND OBJECTIVE

GKRS is an effective treatment for smaller intracranial tumors with a high control rate and low risk of complications. Target delineation in medical MR images is essential in the planning of GKRS and follow-up. A deep learning-based algorithm can effectively segment the targets from medical images and has been widely explored. However, state-of-the-art deep learning-based target delineation uses fixed sizes, and the isotropic voxel size may not be suitable for stereotactic MR images which use different anisotropic voxel sizes and numbers of slices according to the lesion size and location for clinical GKRS planning. This study developed an automatic deep learning-based segmentation scheme for stereotactic MR images.

METHODS

We retrospectively collected stereotactic MR images from 506 patients with VS, 1,069 patients with meningioma and 574 patients with BM who had been treated using GKRS; the lesion contours and individual T1W+C and T2W MR images were extracted from the GammaPlan system. The three-dimensional patching-based training strategy and dual-pathway architecture were used to manage inconsistent FOVs and anisotropic voxel size. Furthermore, we used two-parametric MR image as training input to segment the regions with different image characteristics (e.g., cystic lesions) effectively.

RESULTS

Our results for VS and BM demonstrated that the model trained using two-parametric MR images significantly outperformed the model trained using single-parametric images with median Dice coefficients (0.91, 0.05 versus 0.90, 0.06, and 0.82, 0.23 versus 0.78, 0.34, respectively), whereas predicted delineations in meningiomas using the dual-pathway model were dominated by single-parametric images (median Dice coefficients 0.83, 0.17 versus 0.84, 0.22). Finally, we combined three data sets to train the models, achieving the comparable or even higher testing median Dice (VS: 0.91, 0.07; meningioma: 0.83, 0.22; BM: 0.84, 0.23) in three diseases while using two-parametric as input.

CONCLUSIONS

Our proposed deep learning-based tumor segmentation scheme was successfully applied to multiple types of intracranial tumor (VS, meningioma and BM) undergoing GKRS and for segmenting the tumor effectively from stereotactic MR image volumes for use in GKRS planning.

Outcomes following surgical resection of cystic intracranial meningiomas

INTRODUCTION

Cystic meningiomas are rare, accounting for 2-7% of all intracranial meningiomas. Little is known regarding whether these meningiomas behave differently compared to solid meningiomas. We sought to study this relatively uncommon imaging appearance of meningioma and to evaluate its clinical significance.

METHODS

A single-institution retrospective cohort study of surgically-treated meningioma patients between 2000 and 2019 was conducted. Cystic meningioma was defined as a tumor with an intratumoral or peritumoral cyst present on preoperative imaging. Demographics, preoperative imaging, histopathology characteristics, operative data, and surgical outcomes were reviewed. Imaging variables, histopathology and outcomes were reported for cystic meningiomas and compared with non-cystic meningiomas. Univariate/multivariable analyses were conducted.

RESULTS

Of 737 total meningiomas treated surgically, 38 (5.2%) were cystic. Gross total resection (GTR) was achieved in 84.2% of cystic meningioma patients. Eighty-two percent of cystic meningiomas were WHO grade I (n = 31), 15.7% were grade II and 2.6% were grade III. Most cystic meningiomas had low Ki-67/MIB-1 proliferation index (n = 24, 63.2%). A total of 18.4% (n = 7) patients with cystic meningioma had recurrence compared to 12.2% (n = 80) of patients with non-cystic meningioma (p = 0.228). No significant difference in median time to recurrence was observed between cystic and non-cystic meningiomas (25.4, Q1:13.9, Q3:46.9 months vs. 13.4, Q1:8.6, Q3:35.5 months, p = 0.080).

CONCLUSIONS

A small portion of intracranial meningiomas have cystic characteristics on imaging. Cystic meningiomas are frequently WHO grade I, have low proliferation index, and had similar outcomes compared to non-cystic meningioma. Cysts in meningioma may not be a surrogate to determine aggressive meningioma behavior.

Imaging Features and Pathological Correlation in Mixed Microcystic and Angiomatous Meningioma: A Case Report

Meningiomas are the most common intracranial tumors. However, microcystic and angiomatous meningiomas are very rare subtypes that present unusual imaging findings. Hence, radiological diagnosis of these tumors can be challenging. We herein describe a case of mixed angiomatous and microcystic meningioma in an 81-year-old male. MRI revealed an extra-axial mass with high T2 signal intensity, measuring 1.5 cm in diameter, with multiple tiny intralesional cysts and entrapped peritumoral cyst formation. After tumor resection, a histopathological diagnosis of mixed angiomatous and microcystic meningioma was made.

Neuroradiologic Findings and Clinical Features of Meningiomas With Spontaneous Hemorrhagic Onset: A Single-center 10-year Experience

OBJECTIVE

This study aimed to elucidate the clinicoradiologic features of spontaneous hemorrhagic meningiomas (HMs) and examine risk factors associated with meningioma hemorrhage.

METHODS

We retrospectively reviewed 651 consecutive meningioma patients who underwent surgical resection in our hospital between January 2011 and January 2021. After exclusions, 169 patients were included for analysis. Patients were grouped according to presence of hemorrhage in the meningioma: the HM group (n = 19) and non-HM group (n = 150). Clinicoradiologic patient data were examined and compared using univariate and multivariate analysis.

RESULTS

HMs accounted for 2.9% of the entire series of meningiomas. HMs were mainly located at the convexity (63.2%). Mean diameter of HMs was 4.8 cm. On computed tomography, most HMs appeared as mixed isodensity and hyperdensity (84.2%). On magnetic resonance imaging, most appeared as mixed isointensity and hyperintensity on T1-weighted imaging and mixed hypointesity and hyperintensity on T2-weighted imaging (52.6%). Seventeen tumors exhibited heterogeneous enhancement, a dural tail, and peritumoral brain edema. Thirteen showed intratumoral cystic change. The misdiagnosis rate was significantly higher in HMs than non-HMs (31.6% vs. 7.3%; P = 0.005). Intratumoral cystic change was the only independent predictor of meningioma hemorrhage in multivariate analysis (odds ratio 4.116; 95% confidence interval 1.138-14.894; P = 0.031).

CONCLUSIONS

Mixed isodensity/intensity and hyperdensity/intensity on computed tomography/magnetic resonance imaging in conjunction with heterogenous enhancement, a dural tail, and varying degrees of peritumoral brain edema suggest a high possibility of HM. Presence of intratumoral cystic change was an independent risk factor associated with meningioma hemorrhage.

Cystic meningioma: A case report with a literature review

Cystic meningiomas are very rare tumors of the central nervous system. We report the case of a 62-year-old female how presented headaches resistant to usual analgesics with behavior disorders. Cerebral CT scan showed a right frontal extra-axial tumor with firm and cystic component, brain MRI evoked the diagnosis, surgery removed the entire tumor and histological examination confirmed it. A cystic meningioma should not be omitted from the differential diagnosis of brain tumors with a cystic component and which clinical, radiological, histological and therapeutic features are discussed.

An integrative histopathological and epigenetic characterization of primary intracranial mesenchymal tumors, FET:CREB-fused broadening the spectrum of tumor entities in comparison with their soft tissue counterparts

FET:CREB fusions have been described in a variety of tumors from various phenotypes. Recently, these fusion transcripts were reported in intracranial tumors, variably named intracranial mesenchymal myxoid tumors or angiomatoid fibrous histiocytomas. Controversy remains concerning the terminology for these tumors. Here, we report 11 cases of central nervous system mesenchymal tumors with proven FET:CREB fusion. Most DNA methylation profiles were not classifiable using the Heidelberg Brain Tumor or Sarcoma Classifier (v11b4/v12.2). However, by using unsupervised t‐SNE and hierarchical clustering analyses, six of the cases constituted a distinct cluster. The remaining four tumors showed no obvious relation to any of the other referenced classes but were close to the clusters of extra‐CNS angiomatoid fibrous histiocytomas (n = 1), clear cell sarcomas (n = 1), or solitary fibrous tumors (n = 2). Our findings confirm that intracranial FET:CREB‐fused tumors do not represent a single molecular tumor entity, although most samples clustered close to each other, indicating the existence of a distinct epigenetic group that could potentially be partially masked by the low number of cases included. Further analyses are needed to characterize intracranial FET:CREB fused‐defined tumors in more detail.

A rare cystic lymphoplasmacyte-rich meningioma: A case report and review of the literature

Background:

Meningiomas are common central nervous system neoplasms, accounts for 30% of all primary intracranial neoplasms; the occurrence of meningiomas with cystic lesions is an exceptionally rare. Lymphoplasmacyte-rich meningioma (LPRM) is a rare pathological entity belong to the World Health Organization Grade I meningiomas. LPRM is characterized by abundant lymphoplasmacytic infiltrates which over-shadow the underlying meningothelial component.

Case Description:

A 42-year-old male was admitted to our hospital with a chronic headache for about 3 weeks prior to admission. His symptoms worsen, and subsequently, he experienced left extremities weakness about 1 week before admission. His brain magnetic resonance imaging revealed an irregular and heterogeneously enhancing solid lesion with intratumoral cystic changes at the temporal lobe. A gross total resection was performed; pathological examination revealed a cystic LPRM.

Conclusion:

This rare variant of meningioma is a benign tumor entity featured with massive inflammatory cell infiltration and often less proportion of meningothelial elements. Surgical resection remains the treatment of choice. This is the first report regarding cystic LPRM from Indonesia; we also summarized relevant literature upto-date, May 2020, reported LPRM cases.

Imaging spectrum of meningiomas: a review of uncommon imaging appearances and their histopathological and prognostic significance

Meningiomas are the most common primary non-glial intracranial neoplasms. In most cases, meningiomas have typical imaging appearances and locations, enabling a straightforward radiological diagnosis. However, a myriad of unusual appearances potentially complicate the imaging picture. Furthermore, certain imaging features can also predict the specific histopathological nature and WHO grade of the meningioma. 'Typical' meningiomas include meningothelial, fibrous, and transitional variants and have the characteristic imaging features described for meningiomas. Several 'atypical' variants exist, which, although less common, also generally have a less favourable prognosis and necessitate early diagnosis. In addition, meningiomas can occur in a variety of unusual intracranial and even extra-cranial locations and need to be distinguished from the more common tumours of these regions on imaging. Any associated oedema or haemorrhagic changes may alter the prognosis and have to be carefully assessed and reported. Cystic changes in meningiomas have been divided into five subtypes, and accurate characterisation is essential to predict the prognosis. An extensive review of the several possible variations in imaging appearances of meningiomas including the differential features of common and uncommon variants would facilitate informative radiological reporting of meningiomas. This would be expected to improve pre-operative planning prior to surgical biopsy and thereby improve disease prognosis and patient outcomes.

Fourth Ventricular Meningiomas

OBJECTIVE

Fourth ventricular meningiomas (FVMs) are extremely rare. Here, we report a series of 11 patients at a single institution. A comprehensive literature analysis is conducted.

METHODS

Information about 11 patient was extracted from the patient data. Reports of cases in English were obtained from the literature. Including our 11 patients, 71 patients were analyzed in this study.

RESULTS

The most common age of onset was from the third decade to sixth decade of life. The female/male ratio was about 1.16:1. The most frequent subtype of meningioma was fibrous meningioma. FVMs had specific imaging features, such as calcification (20%), peritumoral edema (30.3%), heterogeneous enhancement (22.5%), cystic formation (4.3%), and hydrocephalus (52.8%). The proportion of total tumor resection was about 94.9%, with 15.3% of postoperative complications. During follow-up, the recurrent rate of FVMs was about 6.8%. There was no significant difference in the analysis of correlation between hydrocephalus and the maximum diameter of tumors, correlation between hydrocephalus and the volume of tumor, or correlation between peritumoral edema and the volume of tumor, as well as correlation between heterogeneous enhancement and the grade of meningiomas.

CONCLUSIONS

FVMs have their own characteristics in age of onset, gender ratio, histologic types, and imaging features. The recommended treatment is surgical treatment via the telovelar approach with suboccipital craniotomy/craniectomy. Adjuvant therapy is needed in some high-grade meningiomas and in patients undergoing partial resection. The prognosis is relatively good, with fewer postoperative complications and a higher rate of total resection.

Differentiating spinal intradural-extramedullary schwannoma from meningioma using MRI T2 weighted images

OBJECTIVE:

Prior studies advocate the subjective visual differences between meningioma and schwannoma on T₂ weighted images, however objective measurement of signal intensity differences may be useful in certain cases. The aim of this study was to investigate whether an objective evaluation of SIs on T₂ weighted images would be useful to differentiate spinal schwannomas from meningiomas.

METHODS:

The patients with spinal MRIs demonstrating path proven and subsequently treated intradural extramedullary spinal tumors were selected between April 2008 and May 2017. Regions of interest (ROIs) were measured in the tumor and subcutaneous fat on the same image, and we calculated the SI ratio between tumor and fat ROIs.

RESULTS:

Twenty patients each with meningioma and schwannoma were enrolled. The SI ratios of schwannomas were significantly higher than those of meningiomas (both researcher 1 and 2: p = 0.002). The areas under the curve by researchers 1 and 2 were 0.780. The cutoff value of SI ratio by both of researchers 1 and 2 to differentiate between schwannomas from meningiomas was 0.420 (sensitivity: 80.0%, specificity: 70.0-75.0%).

CONCLUSION:

The SI ratio, calculated from the SIs of the tumor and fat on T₂ weighted images, is useful for differentiating spinal schwannomas from meningiomas to obtain an accurate diagnosis.

ADVANCES IN KNOWLEDGE:

Signal intensity ratio of the spinal tumor and fat on T₂ weighted images is useful for differentiating schwannomas from meningiomas to obtain an accurate diagnosis.