Case Study
Mediastinal neurothekeoma: A rare tumor Muhammet Sayan1, Ali Celik2, Onur Ertunc3, Omer Uluoglu3 and Abdullah Irfan Tastepe2
Asian Cardiovascular & Thoracic Annals 2015, Vol. 23(5) 593–595 ß The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492314552857 aan.sagepub.com
Abstract Neurothekeoma, also known as nerve sheath myxoma, is a benign nerve sheath tumor that usually arises in the cutaneous nerves of the head, neck, or upper extremities. Extracutaneous placement is very rare. Mediastinal neurothekeoma has not previously been reported in the English literature. A 30-year-old woman was admitted to our clinic with back pain. A smooth-edged mass found in her paravertebral region, and a neurogenic tumor was suspected. The tumor was completely excised. Final pathology revealed it to be a mediastinal neurothekeoma.
Keywords Mediastinal neoplasms, mediastinum, nerve sheath neoplasms, neurothekeoma
Introduction Neurothekeoma is an uncommon benign nerve sheath tumor that usually occurs in the cutaneous region, most commonly on the head and neck. The upper and lower extremities and the trunk are other commonly reported sites of neurothekeoma. Such tumors have rarely been found in the breast, oral cavity, maxilla, and central nervous system.1 Importantly, mediastinal neurothekeoma has never been reported previously in the English literature.
Case report A 30-year-old woman who had complained of periodic back pain for approximately 2 years was admitted to the neurosurgery clinic. Thoracic vertebral magnetic resonance imaging detected a paravertebral mass at the level of the T1–T3 vertebrae (Figure 1). The patient was referred to our clinic. She had no history of abnormality and presented with routine laboratory values. Chest computed tomography showed a smooth-edged lesion, approximately 43 36 32 mm in size, in the left upper paravertebral region. Tumor density was detected at 50 HU. The patient was prepared for an operation with the possibility of a neurogenic tumor. The tumor was completely excised via a posterolateral thoracotomy. The final pathology was mediastinal neurothekeoma (nerve sheath myxoma).
An immunohistochemical study revealed a positive reaction to S-100 protein and a negative reaction to epithelial membrane antigen (Figure 2). There were no problems during the postoperative period and the patient was discharged 4 days after the operation. She has been monitored for 3 years and no recurrence has been detected.
Discussion Neurothekeoma is a benign tumor that originates in the peripheral nerve sheath.2 These tumors were first described in 1969 and were then called nerve sheath myxomas.3 In 1980, Gallagher and Helwig introduced the nomenclature ‘neurothekeoma’ to describe this variety of tumor.4–6 Neurothekeoma is often seen in the head and neck skin of children and young adults.2 These tumors are more common in females.3 Based on the incidence of myxoid stroma, neurothekeoma 1
Division of Thoracic Surgery, Aksaray State Hospital, Aksaray, Turkey Department of Thoracic Surgery, Gazi University School of Medicine, Ankara, Turkey 3 Department of Pathology, Gazi University School of Medicine, Ankara, Turkey 2
Corresponding author: Ali Celik, MD, Department of Thoracic Surgery, Gazi University School of Medicine, Besevler, Ankara 06500, Turkey. Email: [email protected]
Downloaded from aan.sagepub.com at Karolinska Institutets Universitetsbibliotek on November 15, 2015
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Asian Cardiovascular & Thoracic Annals 23(5)
Figure 1. Thoracic magnetic resonance imaging showing a 43 36-mm diameter well-circumscribed mass which was hypointense on T1- and hyperintense on T2-weighted images.
Figure 2. (a) S100-positive immunohistochemistry; the myxoid neurothekeoma subtype demonstrates consistent diffuse S100 protein and glial fibrillary acidic protein immunoreactivity. Immunoperoxidase preparation, original magnification 200. (b) The mucinous stroma contained scattered spindle, polygonal, and stellate-like cells (arrows highlight the ganglion cells). Hematoxylin and eosin stain, original magnification 400.
Downloaded from aan.sagepub.com at Karolinska Institutets Universitetsbibliotek on November 15, 2015
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are divided into myxoid, cellular and mixed subtypes.4 It is generally agreed that the myxoid variant of neurothekeoma (classic type) is of neural origin and is a well-circumscribed lobulated tumor characterized by a high degree of myxomatous changes and low cellularity with scattered spindle cells.5 The cells are found embedded in the myxoid stroma. Immunohistochemical studies of myxoid neurothekeoma have revealed consistent diffuse S100 protein and glial fibrillary acidic protein immunoreactivity, supporting its schwannian differentiation. Its cellular type consists of nest cells and fascicles of epithelioid cells with vesicular nuclei containing limited myxoid stroma. Although the myxoid variant of neurothekeoma is hypocellular, the cellular subtype is hypercellular. Cellular atypia can be seen in cellular neurothekeoma and immunohistochemical staining, where the tumor cells display a strong positive reaction for vimentin, PGP 9.5, and NK1/c3 but only a weak positive reaction for S100 protein.2,7,8 The mixed subtype shows areas of varied cellularity with focal myxoid regions.5 Neurothekeoma may be asymptomatic or occur with various symptoms related to tumor location. A visible mass, pain, or neurogenic signs and symptoms have been reported.1,4,8 The patient in this study presented with back pain but no neurogenic symptoms. Preoperative radiological evaluation can provide information about the neurothekeoma as well as facilitate accurate surgical planning. Neurothekeoma is a soft tissue tumor, therefore, the location of the lesion and the associated surrounding tissue are clearly visible on axial, coronal, and sagittal sections of magnetic resonance imaging. The tumor in this case was hypointense on T1-weighted images and hyperintense on T2-weighted images.1 Because myxoid degeneration can be seen in neurothekeoma, radiological differential diagnosis should be performed to discern this type of tumor from schwannoma, meningioma, neurofibroma, or epidermoid tumors.7 In such tumors, angiography is recommended to detect the vascular patterns. Particularly in the case of intracranial tumors, angiography should also be performed for arterial embolization. Total excision is adequate for the effective treatment of neurothekeoma, and no recurrence has been reported after excision.4 Any local recurrence of the tumor may therefore be the result of incomplete
excision.1 In the literature, there is only one report of a metastatic case.3 Alexandru and colleagues1 reported that neurothekeoma can be treated by total resection and neither chemotherapy or radiation are required. The present case concerned a cellular subtype of neurothekeoma originating from nose skin and a submandibular lymph node metastasis; no recurrence or metastasis was noted 4 years after total excision of the primary tumor and neck dissection.3 Presented at: the Annual Meeting of the Asian Society for Cardiovascular and Thoracic Surgery, Istanbul, April 3–6, 2014 Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest statement None declared.
References 1. Alexandru D, Satyadev R and So W. Neurothekeoma in the posterior fossa: case report and literature review. Perm J 2012; 16: 63–64. 2. Erdem Y, Koktekir E, Bayar MA, Yılmaz A and Caydere M. Characterization of an intracranial neurothekeoma: case report. Turk Neurosurg 2012; 1: 109–112. 3. Akhtar S, Coldewey J and Timmons MJ. Cellular neurothekeoma in the arm of a child. Br J Plast Surg 2004; 57: 572–574. 4. Safadi RA, Hellstein JW, Diab MM and Hammad HM. Nerve sheath myxoma (neurothekeoma) of the gingiva. A case report and review of the literature. Head and Neck Pathol 2010; 4: 242–245. 5. Akhtar K, Zaheer S, Ray PS and Sherwani RK. Myxoid neurothekeoma: a rare soft tissue tumor of the hand in a male toddler. Niger J Surg 2013; 19: 32–34. 6. Gallager RL and Helwig EB. Neurothekeoma—a benign cutaneous tumor of neural origin. Am J Clin Pathol 1980; 74: 759–764. 7. Vered M, Fridman E, Carpenter WM and Buchner A. Classic neurothekeoma (nerve sheath myxoma) and cellular neurothekeoma of the oral mucosa: immunohistochemical profiles. J Oral Pathol Med 2011; 40: 174–180. 8. Vij M, Jaiswal S, Agrawal V, Jaiswal A and Behari S. Nerve sheath myxoma (neurothekeoma) of cerebellopontine angle: case report of a rare tumor with a brief review of literature. Turk Neurosurg 2013; 23: 113–116.
Downloaded from aan.sagepub.com at Karolinska Institutets Universitetsbibliotek on November 15, 2015
Mediastinal neurothekeoma: A rare tumor Muhammet Sayan1, Ali Celik2, Onur Ertunc3, Omer Uluoglu3 and Abdullah Irfan Tastepe2
Asian Cardiovascular & Thoracic Annals 2015, Vol. 23(5) 593–595 ß The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492314552857 aan.sagepub.com
Abstract Neurothekeoma, also known as nerve sheath myxoma, is a benign nerve sheath tumor that usually arises in the cutaneous nerves of the head, neck, or upper extremities. Extracutaneous placement is very rare. Mediastinal neurothekeoma has not previously been reported in the English literature. A 30-year-old woman was admitted to our clinic with back pain. A smooth-edged mass found in her paravertebral region, and a neurogenic tumor was suspected. The tumor was completely excised. Final pathology revealed it to be a mediastinal neurothekeoma.
Keywords Mediastinal neoplasms, mediastinum, nerve sheath neoplasms, neurothekeoma
Introduction Neurothekeoma is an uncommon benign nerve sheath tumor that usually occurs in the cutaneous region, most commonly on the head and neck. The upper and lower extremities and the trunk are other commonly reported sites of neurothekeoma. Such tumors have rarely been found in the breast, oral cavity, maxilla, and central nervous system.1 Importantly, mediastinal neurothekeoma has never been reported previously in the English literature.
Case report A 30-year-old woman who had complained of periodic back pain for approximately 2 years was admitted to the neurosurgery clinic. Thoracic vertebral magnetic resonance imaging detected a paravertebral mass at the level of the T1–T3 vertebrae (Figure 1). The patient was referred to our clinic. She had no history of abnormality and presented with routine laboratory values. Chest computed tomography showed a smooth-edged lesion, approximately 43 36 32 mm in size, in the left upper paravertebral region. Tumor density was detected at 50 HU. The patient was prepared for an operation with the possibility of a neurogenic tumor. The tumor was completely excised via a posterolateral thoracotomy. The final pathology was mediastinal neurothekeoma (nerve sheath myxoma).
An immunohistochemical study revealed a positive reaction to S-100 protein and a negative reaction to epithelial membrane antigen (Figure 2). There were no problems during the postoperative period and the patient was discharged 4 days after the operation. She has been monitored for 3 years and no recurrence has been detected.
Discussion Neurothekeoma is a benign tumor that originates in the peripheral nerve sheath.2 These tumors were first described in 1969 and were then called nerve sheath myxomas.3 In 1980, Gallagher and Helwig introduced the nomenclature ‘neurothekeoma’ to describe this variety of tumor.4–6 Neurothekeoma is often seen in the head and neck skin of children and young adults.2 These tumors are more common in females.3 Based on the incidence of myxoid stroma, neurothekeoma 1
Division of Thoracic Surgery, Aksaray State Hospital, Aksaray, Turkey Department of Thoracic Surgery, Gazi University School of Medicine, Ankara, Turkey 3 Department of Pathology, Gazi University School of Medicine, Ankara, Turkey 2
Corresponding author: Ali Celik, MD, Department of Thoracic Surgery, Gazi University School of Medicine, Besevler, Ankara 06500, Turkey. Email: [email protected]
Downloaded from aan.sagepub.com at Karolinska Institutets Universitetsbibliotek on November 15, 2015
594
Asian Cardiovascular & Thoracic Annals 23(5)
Figure 1. Thoracic magnetic resonance imaging showing a 43 36-mm diameter well-circumscribed mass which was hypointense on T1- and hyperintense on T2-weighted images.
Figure 2. (a) S100-positive immunohistochemistry; the myxoid neurothekeoma subtype demonstrates consistent diffuse S100 protein and glial fibrillary acidic protein immunoreactivity. Immunoperoxidase preparation, original magnification 200. (b) The mucinous stroma contained scattered spindle, polygonal, and stellate-like cells (arrows highlight the ganglion cells). Hematoxylin and eosin stain, original magnification 400.
Downloaded from aan.sagepub.com at Karolinska Institutets Universitetsbibliotek on November 15, 2015
Sayan et al.
595
are divided into myxoid, cellular and mixed subtypes.4 It is generally agreed that the myxoid variant of neurothekeoma (classic type) is of neural origin and is a well-circumscribed lobulated tumor characterized by a high degree of myxomatous changes and low cellularity with scattered spindle cells.5 The cells are found embedded in the myxoid stroma. Immunohistochemical studies of myxoid neurothekeoma have revealed consistent diffuse S100 protein and glial fibrillary acidic protein immunoreactivity, supporting its schwannian differentiation. Its cellular type consists of nest cells and fascicles of epithelioid cells with vesicular nuclei containing limited myxoid stroma. Although the myxoid variant of neurothekeoma is hypocellular, the cellular subtype is hypercellular. Cellular atypia can be seen in cellular neurothekeoma and immunohistochemical staining, where the tumor cells display a strong positive reaction for vimentin, PGP 9.5, and NK1/c3 but only a weak positive reaction for S100 protein.2,7,8 The mixed subtype shows areas of varied cellularity with focal myxoid regions.5 Neurothekeoma may be asymptomatic or occur with various symptoms related to tumor location. A visible mass, pain, or neurogenic signs and symptoms have been reported.1,4,8 The patient in this study presented with back pain but no neurogenic symptoms. Preoperative radiological evaluation can provide information about the neurothekeoma as well as facilitate accurate surgical planning. Neurothekeoma is a soft tissue tumor, therefore, the location of the lesion and the associated surrounding tissue are clearly visible on axial, coronal, and sagittal sections of magnetic resonance imaging. The tumor in this case was hypointense on T1-weighted images and hyperintense on T2-weighted images.1 Because myxoid degeneration can be seen in neurothekeoma, radiological differential diagnosis should be performed to discern this type of tumor from schwannoma, meningioma, neurofibroma, or epidermoid tumors.7 In such tumors, angiography is recommended to detect the vascular patterns. Particularly in the case of intracranial tumors, angiography should also be performed for arterial embolization. Total excision is adequate for the effective treatment of neurothekeoma, and no recurrence has been reported after excision.4 Any local recurrence of the tumor may therefore be the result of incomplete
excision.1 In the literature, there is only one report of a metastatic case.3 Alexandru and colleagues1 reported that neurothekeoma can be treated by total resection and neither chemotherapy or radiation are required. The present case concerned a cellular subtype of neurothekeoma originating from nose skin and a submandibular lymph node metastasis; no recurrence or metastasis was noted 4 years after total excision of the primary tumor and neck dissection.3 Presented at: the Annual Meeting of the Asian Society for Cardiovascular and Thoracic Surgery, Istanbul, April 3–6, 2014 Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest statement None declared.
References 1. Alexandru D, Satyadev R and So W. Neurothekeoma in the posterior fossa: case report and literature review. Perm J 2012; 16: 63–64. 2. Erdem Y, Koktekir E, Bayar MA, Yılmaz A and Caydere M. Characterization of an intracranial neurothekeoma: case report. Turk Neurosurg 2012; 1: 109–112. 3. Akhtar S, Coldewey J and Timmons MJ. Cellular neurothekeoma in the arm of a child. Br J Plast Surg 2004; 57: 572–574. 4. Safadi RA, Hellstein JW, Diab MM and Hammad HM. Nerve sheath myxoma (neurothekeoma) of the gingiva. A case report and review of the literature. Head and Neck Pathol 2010; 4: 242–245. 5. Akhtar K, Zaheer S, Ray PS and Sherwani RK. Myxoid neurothekeoma: a rare soft tissue tumor of the hand in a male toddler. Niger J Surg 2013; 19: 32–34. 6. Gallager RL and Helwig EB. Neurothekeoma—a benign cutaneous tumor of neural origin. Am J Clin Pathol 1980; 74: 759–764. 7. Vered M, Fridman E, Carpenter WM and Buchner A. Classic neurothekeoma (nerve sheath myxoma) and cellular neurothekeoma of the oral mucosa: immunohistochemical profiles. J Oral Pathol Med 2011; 40: 174–180. 8. Vij M, Jaiswal S, Agrawal V, Jaiswal A and Behari S. Nerve sheath myxoma (neurothekeoma) of cerebellopontine angle: case report of a rare tumor with a brief review of literature. Turk Neurosurg 2013; 23: 113–116.
Downloaded from aan.sagepub.com at Karolinska Institutets Universitetsbibliotek on November 15, 2015
