Immunohistochemical profile of the dural tail in intracranial meningiomas.

Abstract

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. 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. 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. 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.