WJ CC
World Journal of Clinical Cases World J Clin Cases 2015 April 16; 3(4): 389-392 ISSN 2307-8960 (online)
Submit a Manuscript: http://www.wjgnet.com/esps/ Help Desk: http://www.wjgnet.com/esps/helpdesk.aspx DOI: 10.12998/wjcc.v3.i4.389
© 2015 Baishideng Publishing Group Inc. All rights reserved.
CASE REPORT
Unusual histological variant of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation Smita Shete, Saroj Bolde, Gopal Pandit, Pushkar Matkari, Sachin B Ingle with rhabdomyoblastic differentiation is called as malignant triton tumor (MTT). It is highly aggressive soft tissue tumor with higher local recurrence rate. MTT has poor prognosis than MPNST. MTT seems to be more aggressive in patients with neurofibromatosis (NF-1). We herein, reporting an interesting case of 55 years male with multiple neurofibromas all over the body since 30 years and multiple café-au-lait spots, diagnosed as NF-1. Since 6 years, he had an enlarged mass in left thigh. Wide excision of mass was done. On histopathological examination revealed the diagnosis of MTT and diagnosis of which was confirmed on immunohistochemistry.
Smita Shete, Saroj Bolde, Gopal Pandit, Pushkar Matkari, Department of Pathology, Dr. Vaishampayan Memorial Government Medical College, Solapur, Maharashtra 4132512, India Sachin B Ingle, Department of Pathology, MIMSR Medical College, Latur, Maharashtra 4132512, India Author contributions: Shete S, Bolde S, Pandit G and Matkari P diagnosed the case and prepared the first draft of manuscript; Ingle SB prepared the final draft of manuscript and revised the intellectual content and gave final approval of manuscript. Ethics approval: According to our ethical committee, as it’s a single case report on tissue histopathology (not on live patient) no need of approval as there is no question of unethical practice. Informed consent: As we are presenting only histopathological diagnosis, not doing any experiments on the live object, we have done only diagnosis in pathology lab so no question of disclosing the patients details name /his consent that is also not indicated. Conflict-of-interest: None is to be declared that is clearly mentioned before submission and also in the copyright form. Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/ licenses/by-nc/4.0/ Correspondence to: Sachin B Ingle, Professor (Secretary Research and Development, MIMSR Medical College, Latur), Department of Pathology, MIMSR Medical College, Ambajogai Road, vishwanathpuram, Latur, Maharashtra 4132512, India. [email protected] Telephone: +91-2382-227424 Fax: +91-2382-228939 Received: October 21, 2014 Peer-review started: October 21, 2014 First decision: December 12, 2014 Revised: January 4, 2015 Accepted: February 4, 2015 Article in press: February 9, 2015 Published online: April 16, 2015
Key words: Malignant triton tumor; Neurofibromatosis-1; Desmin; S-100 protein © The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
Core tip: Meticulous histopathological examination along with immunohistochemistry is the mainstay to arrive at such rare histological diagnosis. The surgical pathologist should keep in mind such rare entity while dealing with such kind of patients. Shete S, Bolde S, Pandit G, Matkari P, Ingle SB. Unusual histological variant of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. World J Clin Cases 2015; 3(4): 389-392 Available from: URL: http://www. wjgnet.com/2307-8960/full/v3/i4/389.htm DOI: http://dx.doi. org/10.12998/wjcc.v3.i4.389
INTRODUCTION Malignant peripheral nerve sheath tumor (MPNST) is an unusual type of soft tissue sarcomas. It accounts for [1] about 5%-10% of all soft tissue sarcomas . Amongst them malignant triton tumor (MTT) constitutes about [2] 5% of all MPNSTs . MTT is a subtype of MPNST that
Abstract Malignant peripheral nerve sheath tumor (MPNST)
WJCC|www.wjgnet.com
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April 16, 2015|Volume 3|Issue 4|
Shete S et al . MPNST with rhabdomyoblastic differentiation has real diagnostic challenge for surgical pathologists with regard to its cell of origin and its relatively aggressive course. It is comprised of malignant Schwann cells coexisting with characteristic malignant [3] rhabdomyoblasts . It occurs in two forms, one is sporadic form and the other is neurofibromatosis type 1 (NF-1) associated form. Majority of the reported cases are of later variety. Immunohistochemically the rhabdomyoblastic elements are typically positive for skeletal muscle markers such as desmin, myoglobin or muscle actin. MTT has a poorer prognosis than [3] MPNST . This poor outcome is mainly attributed to the [4] high frequency of grade Ⅲ histology in this sarcoma .
Figure 1 Photograph showing multiple neurofibromas, present all over the body.
CASE REPORT A 55-year-old male patient presented with multiple swellings all over the body ranging from 1-3 cm since 30 years (Figure 1). These nodules were histopathologically reported as neurofibromas. A subcutaneous nodule in left thigh was enlarged to attain a present size of 8 cm × 4 cm × 3 cm. He had café-au-lait spots on the trunk ranging from 0.5-1.8 mm. On family history, patient’s mother, sister and brother had similar complaints. So he was diagnosed as a case of NF-1. Ultrasonography was suggestive of neoplastic lesion mostly soft tissue sarcoma. Fine needle aspiration cytology was done and reported as malignant soft tissue tumor with possibilities of malignant fibrous histiocytoma and rhabdomyosarcoma (Figure 2A). Complete resection of the mass was done and the specimen was sent for histopathological evaluation. On, gross examination showed a mass of 8 cm × 4 cm × 3 cm in size, covered with skin. Cut surface was soft, pale grey in colour with areas of necrosis. Histopathological examination showed dense areas of malignant spindle shaped cells with oval nuclei with prominent mitoses, marked nuclear pleomorphism along with foci of necrosis. Many nuclei were bizarre and hyperchromatic. Alternating with hypercellular Antoni A areas, there were hypocellular myxoid areascalled as- Antoni B areas. Thick walled congested blood vessels were found. Interspersed within it are seen many Scattered round cells with abundant eosinophilic cytoplasm with atypical nuclei, which were recognized as rhabdomyoblasts (Figure 2B). The surgical cut margins margins were free of tumor invasion. On Immunohistochemical evaluation, spindle cells showed focal S-100 positivity (Figure 3A) and cells with deeply eosinophilic cytoplasm (rhabdomyoblasts) showed positivity for Desmin (Figure 3B). After histopathological confirmation patient was under treatment with radiotherapy and doing well without any recurrence on follow up since last 6 mo till date.
differentiation towards Schwann cells, perineural cells, fibroblasts are labelled as MPNST. This term now replacing the earlier terminologies malignant schwannoma, neurofibrosarcoma and neurogenic [1] sarcoma . The diagnostic criteria for NF-1, is presence [1] of two or more of the following signs : (1) Six or more cafe-au-lait macules; (2) Two or more neurofibromas of any type or one plexiform neurofibroma; (3) Freckling in the axillary or inguinal region; (4) Optic Glioma; (5) Two or more Lisch nodules; (6) Osseous Lesion; and (7) First degree relative (parent, sibling, offspring) with NF-1. MPNST constitutes 5%-10% of all soft tissue sarcomas, about one fourth to one half occur in the setting of [1] neurofibromatosis . Patients with NF-1 have propensity to transform in to sarcoma after a prolonged latent [5] period (10-20 years) . Our patient was diagnosed as having NF-1 and after long latency period of 30 years, he developed MPSNT with rhabdomyoblastic differentiation. MPNST can also arise spontaneously without association [4] of NF-1 . MTT is a rare tumor arising from peripheral nerves. It is an autosomal dominant disorder. It has a strong association with neurofibromatosis (type 1). The common sites of occurrence are head, neck, extremities and [4] trunk . The symptoms are mainly attributed to mass [4] effect giving rise to neurological signs and symptoms . [6] In 1973 Woodnelf et al proposed the classification of MTT by establishing three criteria for diagnosis: (1) Tumor with peripheral nerve involvement in a patient with NF-1; (2) Majority of the cells in the tumor are [6] Schwann cells; and (3) Presence of Rhabdomyoblasts . Our patient had NF-1 and histology showed all the above mentioned criteria. The pathognomic feature of this tumor is the presence of rhabdomyoblasts. The number of rhabdomyoblasts varies from area to area in the same tumor. They are having abundant eosinophilic cytoplasm. Desmin is demonstrated in the rhabdomyoblasts. The histogenesis of this unusual tumor is discussed by Masson. He postulated that both cell lines have similar origin, i.e., from less well differentiated neural [1,7] crest cells . The strong relation between neural
DISCUSSION Peripheral nerve malignant lesions are displaying
WJCC|www.wjgnet.com
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April 16, 2015|Volume 3|Issue 4|
Shete S et al . MPNST with rhabdomyoblastic differentiation
A
B
B
A
Figure 2 Photomicrograph. A: Photomicrograph of cytological smear showing spindle cells with pleomorphic hyperchromatic nuclei and a plump cell (arrow) with abundant eosinophilic cytoplasm; B: Photomicrograph showing hypercellular areas (Antoni A) of spindle cells having hyperchromatic nuclei and hypocellular areas (Antoni B) (100 ×). Inset shows rhabdomyoblastic differentiation (400 ×).
A
B
Figure 3 Immunohistochemistry. A: Immunohistochemistry showing focal S100 positivity in spindle cells; B: Immunohistochemistry showing Desmin positivity in rhabdomyoblasts.
tissues and rhabdomyoblastic differentiation has been reported as the development of skeletal muscle differ entiation within other neural tumors such as Ocular [8] [9,10] Medulloblastoma , Ganglioneuroblastoma . The five years survival rate for MTT is only 11% in contrast to [11] 39% for MPNST . MTT is significantly worse than the usual MPNST. The aggressiveness of MTT is attributed to high grade (grade Ⅲ ) nuclear features with high [4] proliferative capacity . Radical excision followed by high dose radiotherapy is the conventional treatment for this [3] unusual tumor . MTT is an uncommon sarcoma which is having high propensity of local recurrence and distant metastases. Histopathologically, the diagnosis of MPNST with mesenchymal differentiation is difficult. So meticulous histopathological examination and immunohistochemical demonstration of neural markers and skeletal muscle markers help to hit the correct diagnosis. Early diagnosis, complete resection of the tumor followed by radiotherapy can help to increase survival of the patient.
Clinical diagnosis
COMMENTS COMMENTS
2
Multiple neurofibromas.
Differential diagnosis
Neurofibromas, fibrosarcoma, malignant peripheral nerve sheath tumor (MPNST).
Laboratory diagnosis
Fine needle aspiration cytology, histopathology with Immunohistochemistry showing Desmin positivity in rhabdomyoblasts.
Imaging diagnosis
Ultrasonography was suggestive of neoplastic lesion soft tissue sarcoma.
Pathological diagnosis
An unusual histological variant of MPNST with rhabdomyoblastic differentiation.
Experiences and lessons
Careful histological examination along with clinical work up is important to arrive at such unusual diagnosis.
Peer-review
Good overview of the diagnostic challenges in the correct interpretation of this rare tumor.
REFERENCES 1
Case characteristics
A 55-year-old male patient presented with multiple swellings all over the body ranging from 1-3 cm since 30 years.
WJCC|www.wjgnet.com
3
391
Weiss SW, Goldbum JR. Malignant tumors of nerves. In: Weiss SW, Goldblum JR, editors, Enzinger and Weiss’s Soft tissue tumors. St Louis: CV Mosby Elsevier, 2008: 903-944 Brooks JSJ. Disorders of soft tissue. In: Sternberg SS, editor. Diagnostic Surgical Pathology. 3rd ed. Philadelphia: Lipincott Williams and Wilkins, 1999: 131-221 Mae K, Kato Y, Usui K, Abe N, Tsuboi R. A case of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation:
April 16, 2015|Volume 3|Issue 4|
Shete S et al . MPNST with rhabdomyoblastic differentiation
4
5
6
7
malignant triton tumor. Case Rep Dermatol 2013; 5: 373-378 [PMID: 24474920 DOI: 10.1159/000357610] Brooks JS, Freeman M, Enterline HT. Malignant “Triton” tumors. Natural history and immunohistochemistry of nine new cases with literature review. Cancer 1985; 55: 2543-2549 [PMID: 3922610] Guccion JG, Enzinger FM. Malignant Schwannoma associated with von Recklinghausen’s neurofibromatosis. Virchows Arch A Pathol Anat Histol 1979; 383: 43-57 [PMID: 157612] Woodneff JM, Chernik NL, Smith MC. Peripheral nerve tumors with rhabdomyosarcomatous differentiation (Malignant Triton Tumor). Cancer 1973; 32: 626-639 Masson P. Recklinghausen’s Neurofibromatosis, Sensory Neuromas
8 9 10 11
and Motor Neuromas. Libman Anniversary. New York: International press, 1933; 2: 793-802 Zimmerman LE, Font RL, Andersen SR. Rhabdomyosarcomatous differentiation in malignant intraocular medulloepitheliomas. Cancer 1972; 30: 817-835 [PMID: 4116426] Taxy JB, Battifora H, Trujillo Y, Dorfman HD. Electron microscopy in the diagnosis of malignant schwannoma. Cancer 1981; 48: 1381-1391 [PMID: 6791810] Naka A, Matsumoto S, Shirai T. Ganglioneuroblastoma associated with malignant mesenchymoma. Cancer 1976; 36: 1050-1056 Stasik CJ, Tawfik O. Malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation (malignant triton tumor). Arch Pathol Lab Med 2006; 130: 1878-1881 [PMID: 17149968] P- Reviewer: Chaudhry IA S- Editor: Song XX L- Editor: A E- Editor: Lu YJ
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April 16, 2015|Volume 3|Issue 4|
Published by Baishideng Publishing Group Inc 8226 Regency Drive, Pleasanton, CA 94588, USA Telephone: +1-925-223-8242 Fax: +1-925-223-8243 E-mail: [email protected] Help Desk: http://www.wjgnet.com/esps/helpdesk.aspx http://www.wjgnet.com
© 2015 Baishideng Publishing Group Inc. All rights reserved.
World Journal of Clinical Cases World J Clin Cases 2015 April 16; 3(4): 389-392 ISSN 2307-8960 (online)
Submit a Manuscript: http://www.wjgnet.com/esps/ Help Desk: http://www.wjgnet.com/esps/helpdesk.aspx DOI: 10.12998/wjcc.v3.i4.389
© 2015 Baishideng Publishing Group Inc. All rights reserved.
CASE REPORT
Unusual histological variant of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation Smita Shete, Saroj Bolde, Gopal Pandit, Pushkar Matkari, Sachin B Ingle with rhabdomyoblastic differentiation is called as malignant triton tumor (MTT). It is highly aggressive soft tissue tumor with higher local recurrence rate. MTT has poor prognosis than MPNST. MTT seems to be more aggressive in patients with neurofibromatosis (NF-1). We herein, reporting an interesting case of 55 years male with multiple neurofibromas all over the body since 30 years and multiple café-au-lait spots, diagnosed as NF-1. Since 6 years, he had an enlarged mass in left thigh. Wide excision of mass was done. On histopathological examination revealed the diagnosis of MTT and diagnosis of which was confirmed on immunohistochemistry.
Smita Shete, Saroj Bolde, Gopal Pandit, Pushkar Matkari, Department of Pathology, Dr. Vaishampayan Memorial Government Medical College, Solapur, Maharashtra 4132512, India Sachin B Ingle, Department of Pathology, MIMSR Medical College, Latur, Maharashtra 4132512, India Author contributions: Shete S, Bolde S, Pandit G and Matkari P diagnosed the case and prepared the first draft of manuscript; Ingle SB prepared the final draft of manuscript and revised the intellectual content and gave final approval of manuscript. Ethics approval: According to our ethical committee, as it’s a single case report on tissue histopathology (not on live patient) no need of approval as there is no question of unethical practice. Informed consent: As we are presenting only histopathological diagnosis, not doing any experiments on the live object, we have done only diagnosis in pathology lab so no question of disclosing the patients details name /his consent that is also not indicated. Conflict-of-interest: None is to be declared that is clearly mentioned before submission and also in the copyright form. Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/ licenses/by-nc/4.0/ Correspondence to: Sachin B Ingle, Professor (Secretary Research and Development, MIMSR Medical College, Latur), Department of Pathology, MIMSR Medical College, Ambajogai Road, vishwanathpuram, Latur, Maharashtra 4132512, India. [email protected] Telephone: +91-2382-227424 Fax: +91-2382-228939 Received: October 21, 2014 Peer-review started: October 21, 2014 First decision: December 12, 2014 Revised: January 4, 2015 Accepted: February 4, 2015 Article in press: February 9, 2015 Published online: April 16, 2015
Key words: Malignant triton tumor; Neurofibromatosis-1; Desmin; S-100 protein © The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
Core tip: Meticulous histopathological examination along with immunohistochemistry is the mainstay to arrive at such rare histological diagnosis. The surgical pathologist should keep in mind such rare entity while dealing with such kind of patients. Shete S, Bolde S, Pandit G, Matkari P, Ingle SB. Unusual histological variant of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. World J Clin Cases 2015; 3(4): 389-392 Available from: URL: http://www. wjgnet.com/2307-8960/full/v3/i4/389.htm DOI: http://dx.doi. org/10.12998/wjcc.v3.i4.389
INTRODUCTION Malignant peripheral nerve sheath tumor (MPNST) is an unusual type of soft tissue sarcomas. It accounts for [1] about 5%-10% of all soft tissue sarcomas . Amongst them malignant triton tumor (MTT) constitutes about [2] 5% of all MPNSTs . MTT is a subtype of MPNST that
Abstract Malignant peripheral nerve sheath tumor (MPNST)
WJCC|www.wjgnet.com
389
April 16, 2015|Volume 3|Issue 4|
Shete S et al . MPNST with rhabdomyoblastic differentiation has real diagnostic challenge for surgical pathologists with regard to its cell of origin and its relatively aggressive course. It is comprised of malignant Schwann cells coexisting with characteristic malignant [3] rhabdomyoblasts . It occurs in two forms, one is sporadic form and the other is neurofibromatosis type 1 (NF-1) associated form. Majority of the reported cases are of later variety. Immunohistochemically the rhabdomyoblastic elements are typically positive for skeletal muscle markers such as desmin, myoglobin or muscle actin. MTT has a poorer prognosis than [3] MPNST . This poor outcome is mainly attributed to the [4] high frequency of grade Ⅲ histology in this sarcoma .
Figure 1 Photograph showing multiple neurofibromas, present all over the body.
CASE REPORT A 55-year-old male patient presented with multiple swellings all over the body ranging from 1-3 cm since 30 years (Figure 1). These nodules were histopathologically reported as neurofibromas. A subcutaneous nodule in left thigh was enlarged to attain a present size of 8 cm × 4 cm × 3 cm. He had café-au-lait spots on the trunk ranging from 0.5-1.8 mm. On family history, patient’s mother, sister and brother had similar complaints. So he was diagnosed as a case of NF-1. Ultrasonography was suggestive of neoplastic lesion mostly soft tissue sarcoma. Fine needle aspiration cytology was done and reported as malignant soft tissue tumor with possibilities of malignant fibrous histiocytoma and rhabdomyosarcoma (Figure 2A). Complete resection of the mass was done and the specimen was sent for histopathological evaluation. On, gross examination showed a mass of 8 cm × 4 cm × 3 cm in size, covered with skin. Cut surface was soft, pale grey in colour with areas of necrosis. Histopathological examination showed dense areas of malignant spindle shaped cells with oval nuclei with prominent mitoses, marked nuclear pleomorphism along with foci of necrosis. Many nuclei were bizarre and hyperchromatic. Alternating with hypercellular Antoni A areas, there were hypocellular myxoid areascalled as- Antoni B areas. Thick walled congested blood vessels were found. Interspersed within it are seen many Scattered round cells with abundant eosinophilic cytoplasm with atypical nuclei, which were recognized as rhabdomyoblasts (Figure 2B). The surgical cut margins margins were free of tumor invasion. On Immunohistochemical evaluation, spindle cells showed focal S-100 positivity (Figure 3A) and cells with deeply eosinophilic cytoplasm (rhabdomyoblasts) showed positivity for Desmin (Figure 3B). After histopathological confirmation patient was under treatment with radiotherapy and doing well without any recurrence on follow up since last 6 mo till date.
differentiation towards Schwann cells, perineural cells, fibroblasts are labelled as MPNST. This term now replacing the earlier terminologies malignant schwannoma, neurofibrosarcoma and neurogenic [1] sarcoma . The diagnostic criteria for NF-1, is presence [1] of two or more of the following signs : (1) Six or more cafe-au-lait macules; (2) Two or more neurofibromas of any type or one plexiform neurofibroma; (3) Freckling in the axillary or inguinal region; (4) Optic Glioma; (5) Two or more Lisch nodules; (6) Osseous Lesion; and (7) First degree relative (parent, sibling, offspring) with NF-1. MPNST constitutes 5%-10% of all soft tissue sarcomas, about one fourth to one half occur in the setting of [1] neurofibromatosis . Patients with NF-1 have propensity to transform in to sarcoma after a prolonged latent [5] period (10-20 years) . Our patient was diagnosed as having NF-1 and after long latency period of 30 years, he developed MPSNT with rhabdomyoblastic differentiation. MPNST can also arise spontaneously without association [4] of NF-1 . MTT is a rare tumor arising from peripheral nerves. It is an autosomal dominant disorder. It has a strong association with neurofibromatosis (type 1). The common sites of occurrence are head, neck, extremities and [4] trunk . The symptoms are mainly attributed to mass [4] effect giving rise to neurological signs and symptoms . [6] In 1973 Woodnelf et al proposed the classification of MTT by establishing three criteria for diagnosis: (1) Tumor with peripheral nerve involvement in a patient with NF-1; (2) Majority of the cells in the tumor are [6] Schwann cells; and (3) Presence of Rhabdomyoblasts . Our patient had NF-1 and histology showed all the above mentioned criteria. The pathognomic feature of this tumor is the presence of rhabdomyoblasts. The number of rhabdomyoblasts varies from area to area in the same tumor. They are having abundant eosinophilic cytoplasm. Desmin is demonstrated in the rhabdomyoblasts. The histogenesis of this unusual tumor is discussed by Masson. He postulated that both cell lines have similar origin, i.e., from less well differentiated neural [1,7] crest cells . The strong relation between neural
DISCUSSION Peripheral nerve malignant lesions are displaying
WJCC|www.wjgnet.com
390
April 16, 2015|Volume 3|Issue 4|
Shete S et al . MPNST with rhabdomyoblastic differentiation
A
B
B
A
Figure 2 Photomicrograph. A: Photomicrograph of cytological smear showing spindle cells with pleomorphic hyperchromatic nuclei and a plump cell (arrow) with abundant eosinophilic cytoplasm; B: Photomicrograph showing hypercellular areas (Antoni A) of spindle cells having hyperchromatic nuclei and hypocellular areas (Antoni B) (100 ×). Inset shows rhabdomyoblastic differentiation (400 ×).
A
B
Figure 3 Immunohistochemistry. A: Immunohistochemistry showing focal S100 positivity in spindle cells; B: Immunohistochemistry showing Desmin positivity in rhabdomyoblasts.
tissues and rhabdomyoblastic differentiation has been reported as the development of skeletal muscle differ entiation within other neural tumors such as Ocular [8] [9,10] Medulloblastoma , Ganglioneuroblastoma . The five years survival rate for MTT is only 11% in contrast to [11] 39% for MPNST . MTT is significantly worse than the usual MPNST. The aggressiveness of MTT is attributed to high grade (grade Ⅲ ) nuclear features with high [4] proliferative capacity . Radical excision followed by high dose radiotherapy is the conventional treatment for this [3] unusual tumor . MTT is an uncommon sarcoma which is having high propensity of local recurrence and distant metastases. Histopathologically, the diagnosis of MPNST with mesenchymal differentiation is difficult. So meticulous histopathological examination and immunohistochemical demonstration of neural markers and skeletal muscle markers help to hit the correct diagnosis. Early diagnosis, complete resection of the tumor followed by radiotherapy can help to increase survival of the patient.
Clinical diagnosis
COMMENTS COMMENTS
2
Multiple neurofibromas.
Differential diagnosis
Neurofibromas, fibrosarcoma, malignant peripheral nerve sheath tumor (MPNST).
Laboratory diagnosis
Fine needle aspiration cytology, histopathology with Immunohistochemistry showing Desmin positivity in rhabdomyoblasts.
Imaging diagnosis
Ultrasonography was suggestive of neoplastic lesion soft tissue sarcoma.
Pathological diagnosis
An unusual histological variant of MPNST with rhabdomyoblastic differentiation.
Experiences and lessons
Careful histological examination along with clinical work up is important to arrive at such unusual diagnosis.
Peer-review
Good overview of the diagnostic challenges in the correct interpretation of this rare tumor.
REFERENCES 1
Case characteristics
A 55-year-old male patient presented with multiple swellings all over the body ranging from 1-3 cm since 30 years.
WJCC|www.wjgnet.com
3
391
Weiss SW, Goldbum JR. Malignant tumors of nerves. In: Weiss SW, Goldblum JR, editors, Enzinger and Weiss’s Soft tissue tumors. St Louis: CV Mosby Elsevier, 2008: 903-944 Brooks JSJ. Disorders of soft tissue. In: Sternberg SS, editor. Diagnostic Surgical Pathology. 3rd ed. Philadelphia: Lipincott Williams and Wilkins, 1999: 131-221 Mae K, Kato Y, Usui K, Abe N, Tsuboi R. A case of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation:
April 16, 2015|Volume 3|Issue 4|
Shete S et al . MPNST with rhabdomyoblastic differentiation
4
5
6
7
malignant triton tumor. Case Rep Dermatol 2013; 5: 373-378 [PMID: 24474920 DOI: 10.1159/000357610] Brooks JS, Freeman M, Enterline HT. Malignant “Triton” tumors. Natural history and immunohistochemistry of nine new cases with literature review. Cancer 1985; 55: 2543-2549 [PMID: 3922610] Guccion JG, Enzinger FM. Malignant Schwannoma associated with von Recklinghausen’s neurofibromatosis. Virchows Arch A Pathol Anat Histol 1979; 383: 43-57 [PMID: 157612] Woodneff JM, Chernik NL, Smith MC. Peripheral nerve tumors with rhabdomyosarcomatous differentiation (Malignant Triton Tumor). Cancer 1973; 32: 626-639 Masson P. Recklinghausen’s Neurofibromatosis, Sensory Neuromas
8 9 10 11
and Motor Neuromas. Libman Anniversary. New York: International press, 1933; 2: 793-802 Zimmerman LE, Font RL, Andersen SR. Rhabdomyosarcomatous differentiation in malignant intraocular medulloepitheliomas. Cancer 1972; 30: 817-835 [PMID: 4116426] Taxy JB, Battifora H, Trujillo Y, Dorfman HD. Electron microscopy in the diagnosis of malignant schwannoma. Cancer 1981; 48: 1381-1391 [PMID: 6791810] Naka A, Matsumoto S, Shirai T. Ganglioneuroblastoma associated with malignant mesenchymoma. Cancer 1976; 36: 1050-1056 Stasik CJ, Tawfik O. Malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation (malignant triton tumor). Arch Pathol Lab Med 2006; 130: 1878-1881 [PMID: 17149968] P- Reviewer: Chaudhry IA S- Editor: Song XX L- Editor: A E- Editor: Lu YJ
WJCC|www.wjgnet.com
392
April 16, 2015|Volume 3|Issue 4|
Published by Baishideng Publishing Group Inc 8226 Regency Drive, Pleasanton, CA 94588, USA Telephone: +1-925-223-8242 Fax: +1-925-223-8243 E-mail: [email protected] Help Desk: http://www.wjgnet.com/esps/helpdesk.aspx http://www.wjgnet.com
© 2015 Baishideng Publishing Group Inc. All rights reserved.
