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Preoperative embolization of a retroperitoneal malignant nervous sheath tumor
European Journal of Radiology Extra 60 (2006) 117–120
Preoperative embolization of a retroperitoneal malignant nervous sheath tumor Ahmet Do˘grul a,∗ , Erhan Hamalo˘glu a , Barbaros C ¸ il b , Murat Canyi˘git b , a , Ahmet Ozenc ¨ ¨ Arif Ozdemir ¸a b
a Department of General Surgery, Hacettepe University School of Medicine, 06200 Sıhhiye, Ankara, Turkey Department of Vascular Interventional Radiology, Hacettepe University School of Medicine, 06200 Sıhhiye, Ankara, Turkey
Received 16 August 2005; received in revised form 4 September 2006; accepted 4 September 2006
Abstract Malignant peripheral nerve sheath tumors are rare tumors compromising about 5% of all malignant soft tissue tumors. Treatment of these tumors is surgical but surgical resection is not always easy. We are presenting a low grade retroperitoneal malignant peripheral nerve sheath tumor in which we used selective arterial embolization before surgery and surgical resection became possible. © 2006 Elsevier Ireland Ltd. All rights reserved. Keywords: Retroperitoneum; Malignant peripheral nervous sheath tumor; Preoperative embolization
1. Introduction Malignant peripheral nerve sheath tumors are rare tumors compromising about 5% of all malignant soft tissue tumors. Treatment of these tumors is surgical but surgical resection is not always easy. We are presenting a low grade retroperitoneal malignant peripheral nerve sheath tumor in which we used selective arterial embolization before surgery and surgical resection became possible.
2. Case report Ultrasonographic examination of a 52-year-old male patient followed up for gastroesophageal reflux at another center, revealed a retrovesical mass. Pathological examination of tru-cut and fine needle aspiration (FNA) biopsy specimens performed at this center revealed a malignant mesenchymal tumor. Atypical mesenchymal cells were seen in his FNA biopsy specimen whereas immunohistochemical staining of the cells with S-100 protein was positive. Only ∗
Corresponding author. Fax: +90 312 3104071. E-mail address: [email protected] (A. Do˘grul).
1571-4675/$ – see front matter © 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2006.09.004
an incisional biopsy could be performed instead of excision of the lesion because of excessive bleeding. After the operation, the patient was sent to our hospital for further investigation and treatment. In order to visualize the exact location of the lesion, magnetic resonance imaging (MRI) of the pelvic abdomen, performed on a 1.5 T MR with body array coil (Siemens Symphony, Erlagen, Germany), showed a mass located between rectum and urinary bladder. Axial and sagittal T1-weighted MR images (TR/TE, 394/14; slice thickness: 7 mm) after 20 cm3 i.v. gadolinium (Magnevist, Schering AG, Germany) administration show an enhancing mass 15 cm × 11 cm × 13 cm in diameter, compressing rectum posteriorly and the bladder anteriorly. Fat plan between bladder and the mass can be identified which shows there is no invasion to the bladder (Figs. 1 and 2). His computerized tomographic examination revealed no other metastatic lesions in the abdomen and thorax. In accordance with the findings above, embolization of the lesion before the operation was decided. Visceral and bilateral selective internal iliac artery catheterizations were performed following a flush aortogram. The images revealed a hypervascular pelvic mass supplied mainly by the left internal pudendal and superior hemorrhoidal artery (Fig. 3). It was determined that there was no vascular supply from the
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Fig. 1. Sagittal T1-weighted MR image (TR/TE, 394/14) without fat saturation after gadolinium administration shows enhancement of the mass (m), compressing rectum posteriorly (arrowhead) and the bladder (b) anteriorly. Associating fat plan (arrows) between bladder and the mass can be identified which shows there is no invasion to the bladder. Pelvic fluid (f) is demonstrated between rectum and the mass.
right internal iliac artery. Left internal pudendal and superior hemorrhoidal arteries were selectively catheterized with a microcatheter (Fig. 4) (Rapid transit, Cordis Europa, Roden, Netherlands) and the tumor was embolized with 150–250 m
Fig. 2. Axial T1-weighted MR image (TR/TE, 394/14) without fat saturation after gadolinium administration shows enhancement of the mass (m) located between the rectum (arrow) and the bladder (b). Besides, pelvic fluid (f) is demonstrated between rectum and the mass.
Fig. 3. Hypervascular pelvic mass supplied mainly by the left internal pudendal and superior hemorrhoidal artery.
polyvinyl alcohol particles (Contour, Boston Scientific International, Cedex, France). Postembolization control angiography showed nearly total devascularization of the tumor. A radical surgical excision was performed succesfully without any significant blood loss. Pathological examination of the mass was reported as a low grade malignant nervous sheath tumor and its immunostaining for S-100 was positive
Fig. 4. Left internal pudendal and superior hemorrhoidal arteries were selectively catheterized with a microcatheter.
A. Do˘grul et al. / European Journal of Radiology Extra 60 (2006) 117–120
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Fig. 5. (a) Low grade malignant nervous sheath tumor (hematoxylin and eosin stain) and (b) immunostaining for S-100 is positive.
(Fig. 5). By the end of July 2006, he had had a disease free survival of 37 months.
3. Discussion Neural sheath tumors are classified as subclasses of softtissue neoplasms. They include both malignant and benign schwannomas and neurofibromas. Neurofibromas are localized most commonly in the retroperitoneum whereas schwannomas are generally seen in Von Recklinghausen’s disease. In the absence of this disease, the occurence of the tumor in retroperitoneum compromises of only 3% of all schwannomas [1]. Malignant peripheral nervous sheath tumors (MPNSTs) arise from a peripheral nerve of which show intrinsic nerve sheath differentiation. They comprise approximately 5% of all malignant soft tissue tumors. Most derive from neurofibromas or arise de novo from normal peripheral nerves. Most are high grade tumors and have a highly aggresive clinical course. Eighteen percent of MPNSTs was reported as low grade. The diagnosis of low grade MPNST is not easy. Careful clinical and histological evaluations, along with S-100 protein immunostaining, are essential for accurate diagnosis [2]. MPNST commonly presents a diagnostic challenge and may resemble a variety of other soft tissue neoplasms. S100, Myelin basic protein (MBP) and Leu-7 are potential neural markers. These markers were examined by Mark et al. in series of a 62 patients and it was seen that none of them alone is immunospecific for nerve sheath tumors, where coexpression of antigens is important [3].
MRI is the most useful non-invasive diagnostic tool [4] whereas CT guided fine needle aspiration biopsy does not appear to provide an accurate diagnosis [1]. Total surgical excision is the definitive treatment for MPNSTs. Chemotherapy has an unproven benefit. Chemotherapy has no role in the initial treatment of MPNSTs for patients without metastases in whom gross total tumor resection is accomplished. In a series of 54 patients with MPNST, the diameter of the lesion being less than 5 cm and the patient being young were found as favorable prognostic variables [4]. Target sign has been defined as an MRI finding of benign peripheral nerve sheath tumors. The target sign like appearance reflects the mode of tumor formation. Endoneurial myxomatous matrix proliferates, progressively separating myelinated and non-myelinated axons. Schwann cells and collagen fibers proliferate and become embedded in unorganized intercellular material. The non-fibrillary myxomatous tissue accounts for the hyperintense appearence of the periperal zone on T2 weighted sequences, while the central zone of dense collagen is hypointense. MPNSTs have a heterogenous appearance on T2 weighted MR imaging and lack this finding [5]. An irregular, infiltrative tumor border on CT or MRI suggests malignancy but may be present also in benign plexiform neurofibromas. Bone erosion may occur with both benign and malignant lesions. Accordingly, neither CT nor MRI can reliably distinguish malignant from benign nerve sheath neoplasms, although marked inhomogenities, infiltrative margins or irregular bone destruction are more common in MPNSTs [6].
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Stener et al. suggest that in peripheral nerve tumors, malignancy should be strongly suspected when angiography demonstrates high vascularity with many irregular vessels and diffuse opacification with contrast medium [7]. To our knowledge, this is the first case of preoperative embolization of pelvic MPNST in English literature; but total resection of the lesion without major bleeding was performed succesfully with the help of preoperative embolization. We suggest that preoperative embolization can be helpful in selected cases with MPNSTs, but further data is needed.
References [1] Daneshmand S, Youssefzadeha D, Chamiea K, et al. Benign retroperitoneal schwannoma: a case series and review of the literature. Urology 2003;62:993–7.
[2] Yamaguchi U, Hasegava T, Hirose T, et al. Low grade malignant peripheral nervous sheath tumor: varied cytological and histological patterns. J Clin Pathol 2003;56:826–30. [3] Wick MR, Swanson PE, Scheithauer BW, Carlos Manivel J. Malignant peripheral nerve sheath tumor: an immunohistochemical study of 62 cases. Am J Clin Pathol 1987;4:425–33. [4] Baehring JM, Betensky RA, Batchelor TT. Malignant peripheral nerve sheath tumor: the clinical spectrum and outcome of treatment. Neurology 2003;61:696–8. [5] Levine E, Huntrakoon M, Wetzel HL. Malignant nerve-sheath neoplasms in neurofibromatosis: distinction from benign tumors by using imaging techniques. Am J Roentgenol 1987;149(5):1059–64. [6] Bhargava R, Parham DM, Lasater OE, Chari RS, Chen G, Fletcher BD. MR imaging differentiation of benign and malignant peripheral nerve sheath tumors: use of the target sign. Pediatr Radiol 1997;27(2): 124–9. [7] Stener B, Angervall L, Nilsson L, Wickbom I. Angiografic and histological studies of the vascularization of peripheral nerve tumors. Clinic Orthop Rel Res 1969;66:113–24.
Preoperative embolization of a retroperitoneal malignant nervous sheath tumor Ahmet Do˘grul a,∗ , Erhan Hamalo˘glu a , Barbaros C ¸ il b , Murat Canyi˘git b , a , Ahmet Ozenc ¨ ¨ Arif Ozdemir ¸a b
a Department of General Surgery, Hacettepe University School of Medicine, 06200 Sıhhiye, Ankara, Turkey Department of Vascular Interventional Radiology, Hacettepe University School of Medicine, 06200 Sıhhiye, Ankara, Turkey
Received 16 August 2005; received in revised form 4 September 2006; accepted 4 September 2006
Abstract Malignant peripheral nerve sheath tumors are rare tumors compromising about 5% of all malignant soft tissue tumors. Treatment of these tumors is surgical but surgical resection is not always easy. We are presenting a low grade retroperitoneal malignant peripheral nerve sheath tumor in which we used selective arterial embolization before surgery and surgical resection became possible. © 2006 Elsevier Ireland Ltd. All rights reserved. Keywords: Retroperitoneum; Malignant peripheral nervous sheath tumor; Preoperative embolization
1. Introduction Malignant peripheral nerve sheath tumors are rare tumors compromising about 5% of all malignant soft tissue tumors. Treatment of these tumors is surgical but surgical resection is not always easy. We are presenting a low grade retroperitoneal malignant peripheral nerve sheath tumor in which we used selective arterial embolization before surgery and surgical resection became possible.
2. Case report Ultrasonographic examination of a 52-year-old male patient followed up for gastroesophageal reflux at another center, revealed a retrovesical mass. Pathological examination of tru-cut and fine needle aspiration (FNA) biopsy specimens performed at this center revealed a malignant mesenchymal tumor. Atypical mesenchymal cells were seen in his FNA biopsy specimen whereas immunohistochemical staining of the cells with S-100 protein was positive. Only ∗
Corresponding author. Fax: +90 312 3104071. E-mail address: [email protected] (A. Do˘grul).
1571-4675/$ – see front matter © 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2006.09.004
an incisional biopsy could be performed instead of excision of the lesion because of excessive bleeding. After the operation, the patient was sent to our hospital for further investigation and treatment. In order to visualize the exact location of the lesion, magnetic resonance imaging (MRI) of the pelvic abdomen, performed on a 1.5 T MR with body array coil (Siemens Symphony, Erlagen, Germany), showed a mass located between rectum and urinary bladder. Axial and sagittal T1-weighted MR images (TR/TE, 394/14; slice thickness: 7 mm) after 20 cm3 i.v. gadolinium (Magnevist, Schering AG, Germany) administration show an enhancing mass 15 cm × 11 cm × 13 cm in diameter, compressing rectum posteriorly and the bladder anteriorly. Fat plan between bladder and the mass can be identified which shows there is no invasion to the bladder (Figs. 1 and 2). His computerized tomographic examination revealed no other metastatic lesions in the abdomen and thorax. In accordance with the findings above, embolization of the lesion before the operation was decided. Visceral and bilateral selective internal iliac artery catheterizations were performed following a flush aortogram. The images revealed a hypervascular pelvic mass supplied mainly by the left internal pudendal and superior hemorrhoidal artery (Fig. 3). It was determined that there was no vascular supply from the
118
A. Do˘grul et al. / European Journal of Radiology Extra 60 (2006) 117–120
Fig. 1. Sagittal T1-weighted MR image (TR/TE, 394/14) without fat saturation after gadolinium administration shows enhancement of the mass (m), compressing rectum posteriorly (arrowhead) and the bladder (b) anteriorly. Associating fat plan (arrows) between bladder and the mass can be identified which shows there is no invasion to the bladder. Pelvic fluid (f) is demonstrated between rectum and the mass.
right internal iliac artery. Left internal pudendal and superior hemorrhoidal arteries were selectively catheterized with a microcatheter (Fig. 4) (Rapid transit, Cordis Europa, Roden, Netherlands) and the tumor was embolized with 150–250 m
Fig. 2. Axial T1-weighted MR image (TR/TE, 394/14) without fat saturation after gadolinium administration shows enhancement of the mass (m) located between the rectum (arrow) and the bladder (b). Besides, pelvic fluid (f) is demonstrated between rectum and the mass.
Fig. 3. Hypervascular pelvic mass supplied mainly by the left internal pudendal and superior hemorrhoidal artery.
polyvinyl alcohol particles (Contour, Boston Scientific International, Cedex, France). Postembolization control angiography showed nearly total devascularization of the tumor. A radical surgical excision was performed succesfully without any significant blood loss. Pathological examination of the mass was reported as a low grade malignant nervous sheath tumor and its immunostaining for S-100 was positive
Fig. 4. Left internal pudendal and superior hemorrhoidal arteries were selectively catheterized with a microcatheter.
A. Do˘grul et al. / European Journal of Radiology Extra 60 (2006) 117–120
119
Fig. 5. (a) Low grade malignant nervous sheath tumor (hematoxylin and eosin stain) and (b) immunostaining for S-100 is positive.
(Fig. 5). By the end of July 2006, he had had a disease free survival of 37 months.
3. Discussion Neural sheath tumors are classified as subclasses of softtissue neoplasms. They include both malignant and benign schwannomas and neurofibromas. Neurofibromas are localized most commonly in the retroperitoneum whereas schwannomas are generally seen in Von Recklinghausen’s disease. In the absence of this disease, the occurence of the tumor in retroperitoneum compromises of only 3% of all schwannomas [1]. Malignant peripheral nervous sheath tumors (MPNSTs) arise from a peripheral nerve of which show intrinsic nerve sheath differentiation. They comprise approximately 5% of all malignant soft tissue tumors. Most derive from neurofibromas or arise de novo from normal peripheral nerves. Most are high grade tumors and have a highly aggresive clinical course. Eighteen percent of MPNSTs was reported as low grade. The diagnosis of low grade MPNST is not easy. Careful clinical and histological evaluations, along with S-100 protein immunostaining, are essential for accurate diagnosis [2]. MPNST commonly presents a diagnostic challenge and may resemble a variety of other soft tissue neoplasms. S100, Myelin basic protein (MBP) and Leu-7 are potential neural markers. These markers were examined by Mark et al. in series of a 62 patients and it was seen that none of them alone is immunospecific for nerve sheath tumors, where coexpression of antigens is important [3].
MRI is the most useful non-invasive diagnostic tool [4] whereas CT guided fine needle aspiration biopsy does not appear to provide an accurate diagnosis [1]. Total surgical excision is the definitive treatment for MPNSTs. Chemotherapy has an unproven benefit. Chemotherapy has no role in the initial treatment of MPNSTs for patients without metastases in whom gross total tumor resection is accomplished. In a series of 54 patients with MPNST, the diameter of the lesion being less than 5 cm and the patient being young were found as favorable prognostic variables [4]. Target sign has been defined as an MRI finding of benign peripheral nerve sheath tumors. The target sign like appearance reflects the mode of tumor formation. Endoneurial myxomatous matrix proliferates, progressively separating myelinated and non-myelinated axons. Schwann cells and collagen fibers proliferate and become embedded in unorganized intercellular material. The non-fibrillary myxomatous tissue accounts for the hyperintense appearence of the periperal zone on T2 weighted sequences, while the central zone of dense collagen is hypointense. MPNSTs have a heterogenous appearance on T2 weighted MR imaging and lack this finding [5]. An irregular, infiltrative tumor border on CT or MRI suggests malignancy but may be present also in benign plexiform neurofibromas. Bone erosion may occur with both benign and malignant lesions. Accordingly, neither CT nor MRI can reliably distinguish malignant from benign nerve sheath neoplasms, although marked inhomogenities, infiltrative margins or irregular bone destruction are more common in MPNSTs [6].
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A. Do˘grul et al. / European Journal of Radiology Extra 60 (2006) 117–120
Stener et al. suggest that in peripheral nerve tumors, malignancy should be strongly suspected when angiography demonstrates high vascularity with many irregular vessels and diffuse opacification with contrast medium [7]. To our knowledge, this is the first case of preoperative embolization of pelvic MPNST in English literature; but total resection of the lesion without major bleeding was performed succesfully with the help of preoperative embolization. We suggest that preoperative embolization can be helpful in selected cases with MPNSTs, but further data is needed.
References [1] Daneshmand S, Youssefzadeha D, Chamiea K, et al. Benign retroperitoneal schwannoma: a case series and review of the literature. Urology 2003;62:993–7.
[2] Yamaguchi U, Hasegava T, Hirose T, et al. Low grade malignant peripheral nervous sheath tumor: varied cytological and histological patterns. J Clin Pathol 2003;56:826–30. [3] Wick MR, Swanson PE, Scheithauer BW, Carlos Manivel J. Malignant peripheral nerve sheath tumor: an immunohistochemical study of 62 cases. Am J Clin Pathol 1987;4:425–33. [4] Baehring JM, Betensky RA, Batchelor TT. Malignant peripheral nerve sheath tumor: the clinical spectrum and outcome of treatment. Neurology 2003;61:696–8. [5] Levine E, Huntrakoon M, Wetzel HL. Malignant nerve-sheath neoplasms in neurofibromatosis: distinction from benign tumors by using imaging techniques. Am J Roentgenol 1987;149(5):1059–64. [6] Bhargava R, Parham DM, Lasater OE, Chari RS, Chen G, Fletcher BD. MR imaging differentiation of benign and malignant peripheral nerve sheath tumors: use of the target sign. Pediatr Radiol 1997;27(2): 124–9. [7] Stener B, Angervall L, Nilsson L, Wickbom I. Angiografic and histological studies of the vascularization of peripheral nerve tumors. Clinic Orthop Rel Res 1969;66:113–24.