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A Triton tumor mimicking sacrococcygeal teratoma
Journal of Pediatric Surgery (2009) 44, E5–E8
www.elsevier.com/locate/jpedsurg
A Triton tumor mimicking sacrococcygeal teratoma Kaan Sönmez a,⁎, Zafer Türkyılmaz a , Ramazan Karabulut a , Alparslan Kapısız a , Eylem Pınar Eser b , Leyla Memiş b , A. Can Başaklar a a
Department of Pediatric Surgery, Gazi Univercity Medical Faculty, Besevler, Ankara, Turkey Department of Pathology, Gazi Univercity Medical Faculty, Besevler, Ankara, Turkey
b
Received 31 May 2009; revised 24 July 2009; accepted 27 July 2009
Key words: Triton tumor; Newborn; Children
Abstract A newborn female infant delivered after a normal pregnancy was found to have a large sacrococcygeal mass. Imaging and laboratory studies suggested this was a sacrococcygeal teratoma. On the 16th day of age, the tumor was completely removed. Histopathologic examination of the tumor showed malignant Triton tumor (MTT). Thus, we describe a female newborn without a family history of neurofibromatosis with an MTT that mimics a sacrococcygeal teratoma. To our knowledge, this is the first report of a sacrococcygeal MTT detected in a neonate. © 2009 Elsevier Inc. All rights reserved.
Malignant triton tumor (MTT) is a variant of malignant peripheral nerve sheath tumors that contains rhabdomyoblasts. The tumor is thought to be derived from less differentiated neural crest cells that have the ability to differentiate into ectodermal and mesenchymal tissues. It is a rare aggressive tumor with poor prognosis. Some cases are associated with neurofibromatosis type 1 (NF-1) [1,2]. In this report, a newborn without a family history of neurofibromatosis but with an MTT mimicking a sacrococcygeal teratoma is presented.
1. Case report A female newborn was delivered by cesarean delivery after 39 weeks of gestation. Birth weight was 2920 g. The ⁎ Corresponding author. 46.Sokak 28/3, 06490 Bahçelievler, Ankara Turkey. Tel.: +90 312 2026212; fax: +90 312 2230528. E-mail address: [email protected] (K. Sönmez). 0022-3468/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2009.07.042
parents were nonconsanguineous, and the pregnancy was uneventful. On the fourth day of life, the neonate was admitted to our clinic because of a large sacrococcygeal mass. Physical examination revealed a firm, subcutaneous, immobile, painless mass measuring 5 × 5 cm at the sacrococcygeal region (Fig. 1). The baby had no neurologic abnormality. Carcinoembryonic antigen (5.21 ng/mL; reference range, 0-5 ng/mL) and α-fetoprotein plasma levels were high (5920 ng/mL; reference range, 0-13.4 ng/mL). Magnetic resonance imaging showed a well-defined, heterogenous mass 45 × 51 × 47 mm, extending caudally from the coccyx to the inferior limit of the anal canal. No fatty component could be detected within the lesion. The lesion was localized in the fatty tissue, indenting both of the gluteus maximus muscles (Fig. 2A and B). Imaging studies and physical findings suggested that the mass was likely a sacrococcygeal tumor. At surgery, the tumor was firm with distinct margins and surrounded the rectum and anal canal almost completely except for the anterior aspect; however, no infiltration of these tissues was detected. The tumor was adherent to the
E6
K. Sönmez et al. sacrococcygeal area [3]. Malignant Triton tumor should also be considered in the differential diagnosis of sacrococcygeal masses in newborn babies as indicated by this report representing the first case in the literature. Malignant Triton tumor was first described by Mason and Martin in 1938 [4] who noted rhabdomyoblasts within the substance of a peripheral nerve tumor. The designation of MTT was derived from the Triton salamander, which has the ability to regenerate limbs, with both bone and muscle components. This regeneration phenomenon was initially attributed to an ability to regenerate skeletal muscle through
Fig. 1 A subcutaneous mass measuring 5 × 5 cm was palpated in the sacrococcygeal region.
skin on its uppermost limits and in the perianal region. It was removed en bloc through an elliptical incision beginning from the coccyx cranially, extending to the anus, including the coccyx and skin adherent to the tumor, leaving the rectum and the anal canal intact. The wound was closed appropriately, leaving a hemovac drain in place. The resected specimen measured 5 × 5 × 3.5 cm. A pathologic diagnosis of MTT was confirmed by documenting malignant schwannoma associated with rhabdomyoblastic differentiation. Immunohistochemical stains showed that the neoplasm was S-100, desmin, muscle-specific actin (MSA), myogenin, and Myo D1-positive (Fig. 3). On microscopic examination, the margins of the specimen were free of tumor. The drain was removed and oral feedings were started on the third postoperative day. The patient did well until the fourth postoperative day when she had a cardiac arrest and required resuscitation. The cause of this unfortunate event was thought to be pulmonary aspiration. She received mechanical ventilatory support for 1 month and continuous positive airway pressure thereafter. In clinical follow-up, she was diagnosed as having hypoxic encephalopathy. The patient was discharged at the postoperative 80th day with autocontinuous airway positive pressure equipment. During her hospital stay, no local recurrence or distant metastases were detected. Because of the critical situation of the patient, no chemotherapy or radiotherapy was considered. After discharge, we were informed that the patient eventually died.
2. Discussion The differential diagnosis of sacrococcygeal masses includes more than 50 lesions, including teratoma, neuroblastoma, rhabdomyosarcoma, lipoma, and meningomyelocele. However, a sacrococcygeal mass in the newborn period is most often a teratoma. In two thirds of neonates with sacrococcygeal teratoma, a mass is visible at birth over the
Fig. 2 A and B, A midsagittal (T1-weighted) and axial (T2weighted) magnetic resonance images show well-limited mass and extended from the coccyx region to the anus.
A Triton tumor mimicking sacrococcygeal teratoma
Fig. 3 Rhabdomyoblasts showing desmin immunoreactivity in malignant peripheral nerve sheath.
normal nerve induction under the organizing influence of motor nerve fibers [5-7]. The cell of origin of MTT is not known, though the presence of both neural cells and rhabdomyoblasts have led some authors to hypothesize that these 2 cellular components are derived from less differentiated neural crest cells. These cells have both mesodermal and ectodermal differentiation potential and thus possess the ability to develop skeletal and neural components. Direct evidence for the potential of schwannoma cells to exhibit myogenic differentiation has been shown. Three criteria are necessary to establish the diagnosis of MTT: (1) originate from peripheral nerves in patients with von Recklinghausen's disease, (2) predominance of Schwann cell-type growth characteristics, and (3) presence of neoplastic rhabdomyoblasts within the peripheral nerve tumor, not from extension or metastasis from an extrinsic rhabdomyosarcoma. Immunohistochemical staining helps to prove the origin of the cells [7,8]. Antibodies to vimentin, desmin, MSA, cytokeratin, glial fibrillary acidic protein, S100, and Leu-7 are used. Nerve sheath differentiation is confirmed by S-100 protein and Leu-7 (CD57) positivity, whereas rhabdomyoblastic differentiation is confirmed by positivity to desmin, MSA, and myoglobin. The absence of cytokeratin positivity excludes an epithelial origin of the malignancy [7,8]. In the present case, the neoplasm was S-100, desmin, MSA, myogenin, and Myo D1-positive, indicating nerve sheath and rhabdomyoblastic components. In a review, more than 40% of patients with MTT had an associated NF-1 disorder. The literature suggests that MTT arising in any site in patients with NF-1 tends to occur at a younger age [9]. However, we were unable to find any physical signs in the patient or her parents suggesting neurofibromatosis. Nevertheless, genetic counseling was recommended, but the parents declined. Up to 6% of malignant or atypical peripheral nerve tumors, including MTT, are associated with previous radiotherapy [7,10]. More than 50% of MTTs have cytogenetic abnormalities involving chromosome 1—mostly
E7 deletions and translocations [1]. Twenty percent of cases of Triton tumor arise in the head and neck, 32% in the trunk, and 24% in the extremities [7,10,11]. The prognosis is better for head and neck, upper extremity, and lower extremity lesions and worse for tumors of the buttock, trunk, and retroperitoneum [7]. In general, MTT is a high-grade malignant neoplasm with a poor outcome. In a review, only 26% of patients were reported alive without disease, and only 2 of these patients were observed for 5 or more years [7]. Woodruff and Perino [12] had reported crude 2-year and 5-year survival rates of MTT as 15% and 11%, respectively. Most patients have a rapid downhill course, despite amputation and other therapy. In a case of primary retroperitoneal MTT that was incompletely resected, the patient died at 16 weeks despite irradiation and administration of chemotherapy [13]. The main causes of death are tumor recurrence and metastases commonly to lung and brain [14]. Patients with complete tumor resection receiving adjuvant therapy tend to fare better than those who undergo incomplete resection with adjuvant therapy [1-3,5-7]. Malignant Triton tumor is a highly aggressive relatively rare tumor and complete resection of this tumor with or without adjuvant therapy tends to portend improved survival. We suggest that MTT should be considered in the differential diagnosis of neonatal sacrococcygeal tumors and that eligible markers should be measured in the serum and in fresh tumor tissue.
References [1] Velagaleti GV, Miettinen M, Gatalica Z. Malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation (malignant triton tumor) with balanced t(7;9)(q11.2;p24) and unbalanced translocation der(16)t(1;16)(q23;q13). Cancer Genet Cytogenet 2004;149(1):23-7. [2] Ellison DA, Corredor-Buchmann J, Parham DM, Jackson RJ. Malignant triton tumor presenting as a rectal mass in an 11-monthold. Pediatr Dev Pathol 2005;8(2):235-9. [3] Tanaka K, Kanai M, Yosizawa J, Yamazaki Y. A case of neonatal neuroblastoma mimicking Altman type III sacrococcygeal teratoma. J Pediatr Surg 2005;40(3):578-80. [4] Mason P, Martin J. Rhabdomyomes des Nerfs. Bull Assoc Fr Cancer 1938;27:751-67. [5] Cano JR, Algar FJ, Alvarez A, Salvatierra A. Triton tumor of the left sympathetic nerve. Interact Cardiovasc Thorac Surg 2006;5(6):790-1. [6] Haddadin MH, Hawkins AL, Long P, Morsberger LA, Depew D, Epstein JI, Griffin CA. Cytogenetic study of malignant triton tumor: a case report. Cancer Genet Cytogenet 2003;144(2):100-5. [7] Victoria L, McCulloch TM, Callaghan EJ, Bauman NM. Malignant triton tumor of the head and neck: A case report and review of the literature. Head Neck 1999;21(7):663-70. [8] Stasik CJ, Tawfik O. Malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation (malignant triton tumor). Arch Pathol Lab Med 2006;130(12):1878-81. [9] Woodruff JM, Chernik NL, Smith MC, Millett WB, Foote Jr FW. Peripheral nerve tumors with rhabdomyosarcomatous differentiation (malignant “Triton” tumors). Cancer 1973;32(2):426-39. [10] Yakulis R, Manack L, Murphy Jr AI. Postradiation malignant triton tumor. A case report and review of the literature. Arch Pathol Lab Med 1996;120(6):541-8.
E8 [11] Bhatt S, Graeme-Cook F, Joseph MP, Pilch BZ. Malignant triton tumor of the head and neck. Otolaryngol Head Neck Surg 1991;105 (5):738-42. [12] Woodruff JM, Perino G. Non-germ-cell or teratomatous malignant tumors showing additional rhabdomyoblastic differentiation, with emphasis on the malignant Triton tumor. Semin Diagn Pathol 1994;11 (1):69-81.
K. Sönmez et al. [13] Brooks JS, Freeman M, Enterline HT. Malignant “Triton” tumors. Natural history and immunohistochemistry of nine new cases with literature review. Cancer 1985;55(11):2543-9. [14] Rekhi B, Jambhekar NA, Puri A, Agrawal M, Chinoy RF. Clinicomorphologic features of a series of 10 cases of malignant triton tumors diagnosed over 10 years at a tertiary cancer hospital in Mumbai, India. Ann Diagn Pathol 2008;12(2):90-7.
www.elsevier.com/locate/jpedsurg
A Triton tumor mimicking sacrococcygeal teratoma Kaan Sönmez a,⁎, Zafer Türkyılmaz a , Ramazan Karabulut a , Alparslan Kapısız a , Eylem Pınar Eser b , Leyla Memiş b , A. Can Başaklar a a
Department of Pediatric Surgery, Gazi Univercity Medical Faculty, Besevler, Ankara, Turkey Department of Pathology, Gazi Univercity Medical Faculty, Besevler, Ankara, Turkey
b
Received 31 May 2009; revised 24 July 2009; accepted 27 July 2009
Key words: Triton tumor; Newborn; Children
Abstract A newborn female infant delivered after a normal pregnancy was found to have a large sacrococcygeal mass. Imaging and laboratory studies suggested this was a sacrococcygeal teratoma. On the 16th day of age, the tumor was completely removed. Histopathologic examination of the tumor showed malignant Triton tumor (MTT). Thus, we describe a female newborn without a family history of neurofibromatosis with an MTT that mimics a sacrococcygeal teratoma. To our knowledge, this is the first report of a sacrococcygeal MTT detected in a neonate. © 2009 Elsevier Inc. All rights reserved.
Malignant triton tumor (MTT) is a variant of malignant peripheral nerve sheath tumors that contains rhabdomyoblasts. The tumor is thought to be derived from less differentiated neural crest cells that have the ability to differentiate into ectodermal and mesenchymal tissues. It is a rare aggressive tumor with poor prognosis. Some cases are associated with neurofibromatosis type 1 (NF-1) [1,2]. In this report, a newborn without a family history of neurofibromatosis but with an MTT mimicking a sacrococcygeal teratoma is presented.
1. Case report A female newborn was delivered by cesarean delivery after 39 weeks of gestation. Birth weight was 2920 g. The ⁎ Corresponding author. 46.Sokak 28/3, 06490 Bahçelievler, Ankara Turkey. Tel.: +90 312 2026212; fax: +90 312 2230528. E-mail address: [email protected] (K. Sönmez). 0022-3468/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2009.07.042
parents were nonconsanguineous, and the pregnancy was uneventful. On the fourth day of life, the neonate was admitted to our clinic because of a large sacrococcygeal mass. Physical examination revealed a firm, subcutaneous, immobile, painless mass measuring 5 × 5 cm at the sacrococcygeal region (Fig. 1). The baby had no neurologic abnormality. Carcinoembryonic antigen (5.21 ng/mL; reference range, 0-5 ng/mL) and α-fetoprotein plasma levels were high (5920 ng/mL; reference range, 0-13.4 ng/mL). Magnetic resonance imaging showed a well-defined, heterogenous mass 45 × 51 × 47 mm, extending caudally from the coccyx to the inferior limit of the anal canal. No fatty component could be detected within the lesion. The lesion was localized in the fatty tissue, indenting both of the gluteus maximus muscles (Fig. 2A and B). Imaging studies and physical findings suggested that the mass was likely a sacrococcygeal tumor. At surgery, the tumor was firm with distinct margins and surrounded the rectum and anal canal almost completely except for the anterior aspect; however, no infiltration of these tissues was detected. The tumor was adherent to the
E6
K. Sönmez et al. sacrococcygeal area [3]. Malignant Triton tumor should also be considered in the differential diagnosis of sacrococcygeal masses in newborn babies as indicated by this report representing the first case in the literature. Malignant Triton tumor was first described by Mason and Martin in 1938 [4] who noted rhabdomyoblasts within the substance of a peripheral nerve tumor. The designation of MTT was derived from the Triton salamander, which has the ability to regenerate limbs, with both bone and muscle components. This regeneration phenomenon was initially attributed to an ability to regenerate skeletal muscle through
Fig. 1 A subcutaneous mass measuring 5 × 5 cm was palpated in the sacrococcygeal region.
skin on its uppermost limits and in the perianal region. It was removed en bloc through an elliptical incision beginning from the coccyx cranially, extending to the anus, including the coccyx and skin adherent to the tumor, leaving the rectum and the anal canal intact. The wound was closed appropriately, leaving a hemovac drain in place. The resected specimen measured 5 × 5 × 3.5 cm. A pathologic diagnosis of MTT was confirmed by documenting malignant schwannoma associated with rhabdomyoblastic differentiation. Immunohistochemical stains showed that the neoplasm was S-100, desmin, muscle-specific actin (MSA), myogenin, and Myo D1-positive (Fig. 3). On microscopic examination, the margins of the specimen were free of tumor. The drain was removed and oral feedings were started on the third postoperative day. The patient did well until the fourth postoperative day when she had a cardiac arrest and required resuscitation. The cause of this unfortunate event was thought to be pulmonary aspiration. She received mechanical ventilatory support for 1 month and continuous positive airway pressure thereafter. In clinical follow-up, she was diagnosed as having hypoxic encephalopathy. The patient was discharged at the postoperative 80th day with autocontinuous airway positive pressure equipment. During her hospital stay, no local recurrence or distant metastases were detected. Because of the critical situation of the patient, no chemotherapy or radiotherapy was considered. After discharge, we were informed that the patient eventually died.
2. Discussion The differential diagnosis of sacrococcygeal masses includes more than 50 lesions, including teratoma, neuroblastoma, rhabdomyosarcoma, lipoma, and meningomyelocele. However, a sacrococcygeal mass in the newborn period is most often a teratoma. In two thirds of neonates with sacrococcygeal teratoma, a mass is visible at birth over the
Fig. 2 A and B, A midsagittal (T1-weighted) and axial (T2weighted) magnetic resonance images show well-limited mass and extended from the coccyx region to the anus.
A Triton tumor mimicking sacrococcygeal teratoma
Fig. 3 Rhabdomyoblasts showing desmin immunoreactivity in malignant peripheral nerve sheath.
normal nerve induction under the organizing influence of motor nerve fibers [5-7]. The cell of origin of MTT is not known, though the presence of both neural cells and rhabdomyoblasts have led some authors to hypothesize that these 2 cellular components are derived from less differentiated neural crest cells. These cells have both mesodermal and ectodermal differentiation potential and thus possess the ability to develop skeletal and neural components. Direct evidence for the potential of schwannoma cells to exhibit myogenic differentiation has been shown. Three criteria are necessary to establish the diagnosis of MTT: (1) originate from peripheral nerves in patients with von Recklinghausen's disease, (2) predominance of Schwann cell-type growth characteristics, and (3) presence of neoplastic rhabdomyoblasts within the peripheral nerve tumor, not from extension or metastasis from an extrinsic rhabdomyosarcoma. Immunohistochemical staining helps to prove the origin of the cells [7,8]. Antibodies to vimentin, desmin, MSA, cytokeratin, glial fibrillary acidic protein, S100, and Leu-7 are used. Nerve sheath differentiation is confirmed by S-100 protein and Leu-7 (CD57) positivity, whereas rhabdomyoblastic differentiation is confirmed by positivity to desmin, MSA, and myoglobin. The absence of cytokeratin positivity excludes an epithelial origin of the malignancy [7,8]. In the present case, the neoplasm was S-100, desmin, MSA, myogenin, and Myo D1-positive, indicating nerve sheath and rhabdomyoblastic components. In a review, more than 40% of patients with MTT had an associated NF-1 disorder. The literature suggests that MTT arising in any site in patients with NF-1 tends to occur at a younger age [9]. However, we were unable to find any physical signs in the patient or her parents suggesting neurofibromatosis. Nevertheless, genetic counseling was recommended, but the parents declined. Up to 6% of malignant or atypical peripheral nerve tumors, including MTT, are associated with previous radiotherapy [7,10]. More than 50% of MTTs have cytogenetic abnormalities involving chromosome 1—mostly
E7 deletions and translocations [1]. Twenty percent of cases of Triton tumor arise in the head and neck, 32% in the trunk, and 24% in the extremities [7,10,11]. The prognosis is better for head and neck, upper extremity, and lower extremity lesions and worse for tumors of the buttock, trunk, and retroperitoneum [7]. In general, MTT is a high-grade malignant neoplasm with a poor outcome. In a review, only 26% of patients were reported alive without disease, and only 2 of these patients were observed for 5 or more years [7]. Woodruff and Perino [12] had reported crude 2-year and 5-year survival rates of MTT as 15% and 11%, respectively. Most patients have a rapid downhill course, despite amputation and other therapy. In a case of primary retroperitoneal MTT that was incompletely resected, the patient died at 16 weeks despite irradiation and administration of chemotherapy [13]. The main causes of death are tumor recurrence and metastases commonly to lung and brain [14]. Patients with complete tumor resection receiving adjuvant therapy tend to fare better than those who undergo incomplete resection with adjuvant therapy [1-3,5-7]. Malignant Triton tumor is a highly aggressive relatively rare tumor and complete resection of this tumor with or without adjuvant therapy tends to portend improved survival. We suggest that MTT should be considered in the differential diagnosis of neonatal sacrococcygeal tumors and that eligible markers should be measured in the serum and in fresh tumor tissue.
References [1] Velagaleti GV, Miettinen M, Gatalica Z. Malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation (malignant triton tumor) with balanced t(7;9)(q11.2;p24) and unbalanced translocation der(16)t(1;16)(q23;q13). Cancer Genet Cytogenet 2004;149(1):23-7. [2] Ellison DA, Corredor-Buchmann J, Parham DM, Jackson RJ. Malignant triton tumor presenting as a rectal mass in an 11-monthold. Pediatr Dev Pathol 2005;8(2):235-9. [3] Tanaka K, Kanai M, Yosizawa J, Yamazaki Y. A case of neonatal neuroblastoma mimicking Altman type III sacrococcygeal teratoma. J Pediatr Surg 2005;40(3):578-80. [4] Mason P, Martin J. Rhabdomyomes des Nerfs. Bull Assoc Fr Cancer 1938;27:751-67. [5] Cano JR, Algar FJ, Alvarez A, Salvatierra A. Triton tumor of the left sympathetic nerve. Interact Cardiovasc Thorac Surg 2006;5(6):790-1. [6] Haddadin MH, Hawkins AL, Long P, Morsberger LA, Depew D, Epstein JI, Griffin CA. Cytogenetic study of malignant triton tumor: a case report. Cancer Genet Cytogenet 2003;144(2):100-5. [7] Victoria L, McCulloch TM, Callaghan EJ, Bauman NM. Malignant triton tumor of the head and neck: A case report and review of the literature. Head Neck 1999;21(7):663-70. [8] Stasik CJ, Tawfik O. Malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation (malignant triton tumor). Arch Pathol Lab Med 2006;130(12):1878-81. [9] Woodruff JM, Chernik NL, Smith MC, Millett WB, Foote Jr FW. Peripheral nerve tumors with rhabdomyosarcomatous differentiation (malignant “Triton” tumors). Cancer 1973;32(2):426-39. [10] Yakulis R, Manack L, Murphy Jr AI. Postradiation malignant triton tumor. A case report and review of the literature. Arch Pathol Lab Med 1996;120(6):541-8.
E8 [11] Bhatt S, Graeme-Cook F, Joseph MP, Pilch BZ. Malignant triton tumor of the head and neck. Otolaryngol Head Neck Surg 1991;105 (5):738-42. [12] Woodruff JM, Perino G. Non-germ-cell or teratomatous malignant tumors showing additional rhabdomyoblastic differentiation, with emphasis on the malignant Triton tumor. Semin Diagn Pathol 1994;11 (1):69-81.
K. Sönmez et al. [13] Brooks JS, Freeman M, Enterline HT. Malignant “Triton” tumors. Natural history and immunohistochemistry of nine new cases with literature review. Cancer 1985;55(11):2543-9. [14] Rekhi B, Jambhekar NA, Puri A, Agrawal M, Chinoy RF. Clinicomorphologic features of a series of 10 cases of malignant triton tumors diagnosed over 10 years at a tertiary cancer hospital in Mumbai, India. Ann Diagn Pathol 2008;12(2):90-7.