Recurrence of convexity meningiomas: tumor cells in the arachnoid membrane

Kamitani, Hiroshi; Masuzawa, Hideaki; Kanazawa, Itaru; Kubo, Tetsuo

doi:10.1016/s0090-3019(01)00582-1

Cited by 44 publications

(23 citation statements)

References 28 publications

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“…Whereas no association emerged with the former, a low SEMA3A expression was significantly associated to the development of recurrences in the group of patients harboring a Simpson's grade 1 meningioma. It has been suggested that the development of recurrences of totally resected (Simpson's grade 1) meningiomas may be related to the presence of microscopic clusters of neoplastic cells left in the dura mater or in the arachnoid membrane [31,32] and we may hypothesize that this event depends upon the biological activity of these cells. As specified above, we found that the recurrent tumors of our series displayed a significantly lower SEMA3A expression, as well as significantly higher MVD and growth fraction.…”

Section: Discussionmentioning

confidence: 90%

Semaphorin3A immunohistochemical expression in human meningiomas: correlation with the microvessel density

2009

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The immunoexpression of the antiangiogenic factor semaphorin3A (SEMA3A) was evaluated in a series of meningiomas. Then, its correlations with the microvessel density (MVD) of the tumors and with the clinicopathological parameters as well with the survival time or recurrence-free interval were investigated. A positive SEMA3A immunostaining was found in most of meningiomas and a significant association was found between a high expression of this protein and a low MVD of the tumors. Moreover, a low SEMA3A immunoexpression was significantly correlated with a higher recurrence rate of meningiomas. In conclusion, our findings suggest a role for SEMA3A as an antiangiogenic factor in meningiomas with its decrease being associated with the development of recurrences. The supplementation of SEMA3A might be used in novel therapeutic antiangiogenic strategies to prevent the recurrence of highly vascularized meningiomas.

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Section: Discussionmentioning

confidence: 90%

Semaphorin3A immunohistochemical expression in human meningiomas: correlation with the microvessel density

2009

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“…Finally, similar to what is shown in ovarian cancer, 20 a high VEGF/SEMA3A ratio was significantly associated with the development of recurrences in the group of patients harboring a Simpson's grade 1 meningioma. It has been suggested that the development of recurrences of totally resected (Simpson's grade 1) meningiomas may be related to the presence of microscopic clusters of neoplastic cells left in the dura mater or in the arachnoid membrane 32,33 and we may hypothesize that this event depends upon the biological activity of these cells. As specified above, we found that the recurrent tumors of our series displayed significantly higher VEGF/SEMA3A, MVD and growth fraction as well as significantly lower SEMA3A expression.…”

Section: Discussionmentioning

confidence: 92%

Increased ratio of vascular endothelial growth factor to semaphorin3A is a negative prognostic factor in human meningiomas

Barresi¹,

Tuccari²

2010

Neuropathology

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Semaphorin3A (SEMA3A) is an anti-angiogenic factor which is expressed in human meningiomas in association with low microvessel density (MVD). It competes with vascular endothelial growth factor (VEGF) for receptor neuropilin-1 (NRP-1). The ratio between VEGF and SEMA3A has been recently demonstrated to regulate neo-angiogenesis, proliferation and progression of tumors. To clarify the involvement of these proteins in the above-mentioned phenomena, we analyzed the immunohistochemical expression of SEMA3A, VEGF and NRP-1 and their correlation with MVD in a series of 48 cases of meningioma with different histotype and histological grade. SEMA3A and VEGF expression was encountered in about half the cases, although at different levels. NRP-1 staining was evidenced in the vessels within all but two tumors and in the neoplastic cells of 18/48 meningiomas. A negative significant correlation emerged between SEMA3A amount and MVD; on the other hand, high VEGF levels appeared to be significantly associated with high MVD. A high VEGF/SEMA3A was significantly associated with high histological grade, proliferation index and MVD as well as with a higher recurrence rate of the meningiomas. Present data suggest that the balance between the expression of the pro-angiogenic factor VEGF and the anti-angiogenic SEMA3A may be involved in the regulation of neo-angiogenesis and proliferation in meningiomas, representing also a predictor of recurrences in these tumors. Further validation of our results may open the way for the use of drugs targeting not only VEGF, but also NRP-1 and SEMA3A to prevent recurrences of meningiomas.

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“…Although predominantly benign, these brain tumors often recur even after apparently complete resection. 27 Unfortunately, there are no per-operative tools to make sure whether or not all tumor tissue has been removed. The real extent of failure is therefore unknown until the tumor has grown significantly.…”

Section: Meningiomamentioning

confidence: 99%

Tissue characterization using high wave number Raman spectroscopy

Koljenović¹,

Schut²,

Wolthuis³

et al. 2005

J. Biomed. Opt.

131

117

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Raman spectroscopy is a powerful diagnostic tool, enabling tissue identification and classification. Mostly, the so-called fingerprint (approximately 400-1800 cm(-1)) spectral region is used. In vivo application often requires small flexible fiber-optic probes, and is hindered by the intense Raman signal that is generated in the fused silica core of the fiber. This necessitates filtering of laser light, which is guided to the tissue, and of the scattered light collected from the tissue, leading to complex and expensive designs. Fused silica has no Raman signal in the high wave number region (2400-3800 cm(-1)). This enables the use of a single unfiltered fiber to guide laser light to the tissue and to collect scattered light in this spectral region. We show, by means of a comparison of in vitro Raman microspectroscopic maps of thin tissue sections (brain tumors, bladder), measured both in the high wave number region and in the fingerprint region, that essentially the same diagnostic information is obtained in the two wave number regions. This suggests that for many clinical applications the technological hurdle of designing and constructing suitable fiber-optic probes may be eliminated by using the high wave number region and a simple piece of standard optical fiber.

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Recurrence of convexity meningiomas: tumor cells in the arachnoid membrane

Cited by 44 publications

References 28 publications

Semaphorin3A immunohistochemical expression in human meningiomas: correlation with the microvessel density

Semaphorin3A immunohistochemical expression in human meningiomas: correlation with the microvessel density

Increased ratio of vascular endothelial growth factor to semaphorin3A is a negative prognostic factor in human meningiomas

Tissue characterization using high wave number Raman spectroscopy

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