Expression of mesothelioma-related markers in meningiomas: an immunohistochemical study

A case of multiples liver metastases from a grade 2 brain meningioma: a rare entity with comprehensive literature review

Introduction and importance

Meningiomas are primary benign extra-axial central nervous system neoplasms that originate in meningothelial cells. Extra-neurological metastases are quite rare and occur in 0.1% of cases. The main metastatic sites are usually the lungs, bones, pleura, mediastinum and lymph nodes. Hepatic locations are quite rare and account for ~3% of all extracranial metastases. The dissemination route is still a subject of debate. Suggested routes of dissemination include the venous system, lymph nodes, or even cerebrospinal fluid. The treatment is based on complete surgical excision or on radiosurgery and adjuvant radiotherapy in case of subtotal resection.

Case presentation

The authors present the following clinical case of a 31-year-old healthy male patient with surgical history of meningioma excisions, who presents, 3 years later, evidence of liver masses on tomography and confirmed diagnosis of liver metastases from brain meningioma after biopsy with favorable outcomes after chemotherapy.

Clinical discussion

The overall incidence of extra-neurological metastases of meningiomas remains low. The vast majority of these metastases concern those of high grade, namely WHO grade 2 and 3 as it was reported in our case. Hepatic metastases remain quite rare and account for ~3% of all extracranial locations. Due to these characteristics of having low recurrence and its rare frequency of metastasis to extracranial sites, the authors, through their case, will dig into the literature to dissect this rare entity.

Conclusion

In the report of liver lesions, the first differential diagnosis in mind should be metastatic lesions, if there is a prior clinical history of primary tumors.

Calcifying pseudoneoplasm of neuroaxis (CAPNON): a comprehensive immunohistochemical and morphological characterization of five cases

Calcifying pseudoneoplasm of neuroaxis (CAPNON) is a rare lesion of the central nervous system with uncertain histogenesis. We further explored phenotypic spectrum of the entity with respect to possible histogenesis. We collected 5 cases of CAPNONs, performed a detailed morphological assessment, and performed an extensive immunohistochemical analysis (EMA, progesterone receptors, MUC4, SSTR2A, cytokeratin AE1/3, cytokeratin 18, GFAP, neurofilaments, desmin, nestin, synaptophysin, S100 protein, SOX10, CD56, Podoplanin, SATB2, ERG, CD45, and CD163) to elucidate the histogenesis. Furthermore, we performed NGS analysis of one case. The clinical course was benign in all cases. All lesions showed extensively calcified matrix in multilobular arrangement, with a palisade of osteoblast-like cells. Characteristic fibrohyaline matrix was notable in 4/5 cases, while one case was myxoid with rod-like calcifications. Metaplastic lamellar bone was present in 4/5 cases and psammoma bodies were present in 2/5 cases. In 4/5 cases, areas of entrapped glial tissue were present. Expression of EMA was focally present in 3/5 cases, SSTR2A and nestin in 2/5 cases, and progesterone receptor in 2/5 cases in rare cells. We did not observe concomitant expression of EMA, SSTR2A, and progesterone receptor in the same cellular subsets. In one case, NGS showed multiple chromosomal alterations and missense mutation in PIK3CA, attributable to the admixed meningothelial population compatible with meningioma. In another case, biphasic proliferation with myoepithelial phenotype was present. The lesions showed no lineage-specific immunoprofile. Additional pathology was identified in two cases, furthermore suggestive of a possible reactive origin of the lesion.

The density of microvessels positive for Wilms' tumour-1 protein (WT-1) is an independent predictor of recurrence risk in meningiomas

Wilms' tumour-1 (WT-1) protein m-RNA was recently demonstrated in meningiomas, suggesting the potential application of WT-1 immunotherapy in these tumours. The aim of the present study was to analyze the immunohistochemical expression of WT-1 protein, its correlation with the clinico-pathological variables and association with vascular endothelial growth factor (VEGF) expression, in a series of 60 meningiomas of different histotype and histological grade. None of the cases expressed WT-1 in the neoplastic cells, while endothelial expression was evidenced in a variable number of tumour vessels in all the meningiomas. The density of microvessels positive for WT-1 (WT-1 MVD) was significantly higher in meningiomas showing higher histological grade (P = 0.0191), growth fraction (P = 0.0201), expression of VEGF (P = 0.0288) and recurrence risk (P = 0.022). In addition, high WT-1 MVD was a significant independent predictive factor for a shorter recurrence-free survival (RFS) in patients with completely resected meningiomas (P = 0.0028). In conclusion, this study shows that WT-1 MVD is correlated with the biological aggressiveness of meningiomas. Although no staining for WT-1 was evidenced in the neoplastic cells of these tumours, WT-1 endothelial expression in the tumour vessels might represent a target for WT-1 immunotherapy in the aim of reducing their blood supply and growth.

Immunohistochemical profile of the dural tail in intracranial meningiomas

OBJECTIVE

The dural tail sign was first described as a thin, tapering rim of dural enhancement, in continuity with meningiomas on enhanced T1-weighted magnetic resonance (MR) images. However, the exact nature of the dural tail is still unclear. This study investigated the immunohistochemical (IHC) characteristics of the dural tail in intracranial meningiomas and the correlation between clinicopathological profiles and tumor invasion of the dural tail.

METHODS

The study group consisted of 36 patients of meningioma with the dural tail noted on MR imaging and in pathological findings, and 18 patients of meningioma without the dural tail as the control group. IHC staining of tumor masses and dural tails for vascular endothelial growth factor (VEGF), epithelial membrane antigen, CD34, Ki-67, and vimentin were performed.

RESULTS

The data showed that 61.1 % (22/36) of cases in the study group revealed tumor invasion of dural tail, and 55.6 % (30/54) of all the cases demonstrated dura mater invasion in all the samples. The dura mater invasion was significantly positively related to invasion of the dural tail in the study group (p = 0.009). IHC staining detected higher expression of VEGF and CD34 in the dural tail than in the main tumor mass.

CONCLUSIONS

Considering the high proportion of patients with tumor invasion into the dural tail, we tried to perform wide resection of the dural tail during intracranial meningioma surgery. Furthermore, VEGF was strongly expressed in tumor cells that invaded into the dural tail, and hence VEGF can be used as a marker to differentiate tumor cells from normal meningeal cells in the dural tail.