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Lipoblastoma of the neck: a case report and literature review
Lipoblastoma of the Neck: A Case Report and Literature Review Mayuko Sakaida, MD, Takeshi Shimizu, MD, Chikako Kishioka, MD, and Yuichi Majima, MD Lipoblastoma is a rare benign tumor arising from embryonic white fat. We describe a case of huge lipoblastoma of the neck in a 1-year-old boy. Magnetic resonance imaging (MRI) revealed a 7 ⫻ 7 cm neck mass that extruded into the parapharyngeal and paratracheal spaces. At the operation, a well-circumscribed and extensively growing tumor was completely removed. Histopathologic examination showed that the tumor contained lobulated mature adipose tissue and myxoid tissue with lipoblasts and other immature fat cells. The postoperative course was uneventful, and no recurrence of tumor has been noted in more than 2 years follow-up. (Am J Otolaryngol 2004;25:266-269. © 2004 Elsevier Inc. All rights reserved.)
Lipoblastoma is a rare benign tumor that occurs in infancy and early childhood. This tumor commonly arises from the limbs and trunk, and involvement of the neck is extremely rare. To date, 12 cases of cervical lipoblastoma have been reported in the English literature. The most common presentation is a painless neck mass, but the compression of cervical structures results in respiratory insufficiency.1,2 Horner’s syndrome1,3 and hemiparesis.3 Magnetic resonance imaging (MRI) is particularly useful to define the extent of the lesion and to evaluate the preoperative diagnosis. Lipoblastoma is rapidly growing, and complete surgical excision is recommended; there are reported recurrences after inadequate excision. Diagnosis is determined by histopathologic findings. In this article, we describe a rare case of cervical lipoblastoma in a 1-year-old boy. Clinical manifestations, radiologic and histopathologic findings, and treatment of this lesion are discussed.
From the Department of Otorhinolaryngology, Mie University School of Medicine, Mie, Japan. Address correspondence to: Mayuko Sakaida, MD, Department of Otorhinolaryngology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 5148507, Japan. E-mail: [email protected]. © 2004 Elsevier Inc. All rights reserved. 0196-0709/$ - see front matter doi:10.1016/j.amjoto.2003.12.008 266
CASE REPORT A 1-year-old boy presented to the Department of Otorhinolaryngology, Mie University Hospital, with a history of painless swelling in the left neck for 3 months that rapidly enlarged. The patient did not have a stridor, dyspnea, or dysphagia. He had a history of cardiovascular surgery for the complete transposition of great arteries and ventricular septal defect. Physical examination revealed a huge neck mass that was smooth and soft (Fig 1). The neurologic examination was unremarkable. MRI showed a 7 ⫻ 7 cm expansive mass that extruded into the parapharyngeal and paratracheal spaces. The larynx and trachea were displaced to the right (Fig 2). Both T1weighted and T2-weighted imaging showed a lobulated fatty mass with high signal intensity, but it was hypointense to subcutaneous fat on T1-weighted images. At the operation, a 10 ⫻ 6 ⫻ 5 cm, wellcircumscribed, yellowish-white mass was completely removed. There was no invasion of any of the neck structures. Macroscopic examination revealed a well-encapsulated lobulated mass. The cut surface was mostly fat-like, but partially occupied by gray-white gelatinous tissues. Microscopically, the tumor consisted of lobulated mature adipose tissue with loose fibrous septa. Some lobes contained myxoid and immature adipose tissue, with immature stellate to spindled mesenchy-
American Journal of Otolaryngology, Vol 25, No 4 (July-August), 2004: pp 266-269
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267
of airways and cervical sympathetic trunk, respectively. O’Donnel et al3 reported the case with weakness of upper extremity caused by the mild compression of spinal cord. In this case, the tumor extruded into the parapharyngeal and paratracheal spaces and displaced the trachea and larynx to the other side; however, the patient had no respiratory symptom. MRI is particularly useful for the preoperative evaluation and diagnosis. Although computed tomography can show the fat-dense
Fig 1. A soft and huge mass on the left side of the neck. Figure can be viewed in color online.
mal cells and multivacuolated lipoblasts (Fig 3). The histopathologic diagnosis was lipoblastoma. The postoperative course was uneventful, and no recurrence has been noted in more than 2 years follow-up. DISCUSSION Lipoblastoma and lipoblastomatosis are rare benign tumors arising from fetal embryonal white fat. In 1926, Jaffe4 used the term lipoblastoma to describe a tumor of immature fat cells, and, in 1958, Vellious et al5 described lipoblastomatosis as benign neoplasm of fetal fat tissue of the postnatal period. Chung and Enzinger,6 in 1973, suggested the term benign lipoblastoma to be used for the circumscribed type, and the term lipoblastomatosis for the diffuse multicentric type of this neoplasm. The patients’ age ranged from 5 days to 18 years,6-10 with more than 80% cases occurring before the age of 3 years.6,11 They commonly arise from extremities (30%70%) and trunk (20%-50%), and involvement of the neck is rare (10%-15%).6-10,12 To date, 169 cases of lipoblastoma and lipoblastomatosis (34 cervical cases) have been reported in the English literature, and only 12 cases were reported to be lipoblastoma of the neck. The most common presentation of cervical lipoblastoma is a rapidly growing painless mass. Two of the 12 cases had respiratory insufficiency,1,2 and 2 other cases had Horner’s syndrome1,3 caused by the compression
Fig 2. (A) Axial and (B) sagittal MRI on T1-weighted images showing a large fatty tumor that extruded into the parapharyngeal and the paratracheal spaces. Larynx and trachea are displaced to the right.
268
Fig 3. Microscopic view showing (A, arrows) multivacuolated lipoblasts and (B, arrows) spindle-shaped, immature mesenchymal cells in a myxoid stroma (hematoxylin and eosin, ⴛ400). Figure can be viewed in color online.
mass containing the enhanced septa, MRI can suggest the histology of some component of the tumor. Lipoblastoma is mostly high-signal intensity on both T1-weighted and T2weighted images but shows lower signal intensity than mature fat tissue on T1-weighted images. The area with mature fat tissue is found as the area of high-signal intensity on T1-weighted images, and the fibrous septa are hypointense.14,16 The high-signal intensity on T2-weighted images may be caused by the rich myxoid stroma with numerous lipoblasts.14-16 None of these findings, however, are diagnostic of lipoblastoma because these findings can be noted with many benign and malignant fatty tumors, such as lipoma, hibernoma, and liposarcoma. The only definitive procedure to diagnosis is biopsy or surgical excision and pathologic proof. Histopathologically, lipoblastoma consists of lobulated adipose tissue with fibrous septa
SAKAIDA ET AL
and possesses eosinophilic mucinous to myxoid stroma with immature adipocytes, which include poorly differentiated stellate to spindled mesenchymal cells, multivacuolated lipoblasts, and nearly mature adipocytes.7 Pleomorphism and cytologic atypia are lacking, but mitotic activity may be seen. Other fat tissue tumors also have histologic similarities to lipoblastoma. Lipoma, fibrolipoma, and angiolipoma have lobules with fibrous septa but lack of lipoblasts.17 Hibernoma also displays a lobular pattern but consists entirely of brown fat cells with eosinophilic, granular cytoplasm.17 Myxoid liposarcoma has lobulation and myxoid stroma, but it may be rare in children, mainly after 15 years old, and there is a significant degree of cellular pleomorphism with nuclear atypia, atypical multivacuolated lipoblasts, and atypical mitotic figures.7,17 Recent cytogenetic analysis revealed specific chromosomal abnormalities in adipose tissue tumors. In the case of lipoblastoma, cytogenetic breakpoint abnormalities occur consistently in the chromosome 8q11-q13.7 Other adipose tissue tumors may also have characteristic cytogenetic abnormalities; lipoma shows variable translocations in chromosome 12. Myxoid liposarcoma is characterized by the translocation t(12;16)(q13;p11), and hibernoma shows the rearrangement in chromosome 11q13. In this case, we did not examine the chromosomal analysis; however, this procedure will be helpful for the diagnosis of these adipose tissue tumors. Complete surgical excision is the treatment of choice. Local recurrences are reported in 14% to 25%7 of the lipoblastoma and lipoblastomatosis cases, and they have been attributable to an incomplete excision. In cases of lipoblastoma, recurrence is rare and no recurrence has been reported in the 12 cases with cervical lipoblastoma. REFERENCES 1. Gammelgaard N, Jorgensen K, Lund C, et al: Benign Lipoblastoma in the neck causing respiratory insufficiency. Laryngoscope 93:935-937, 1983 2. Rasmusen LS, Kirkegaad J, Kaasbol M: Intermittent airway obstruction in a child caused by a cervical lipoblastoma. Acta Anaesthesiol Scand 41:945-946, 1997 3. O’Donnel KA, Caty MG, Allen IE, et al: Lipoblastoma: Better termed infantile lipoma? Pediatr Surg Int 16:458-461, 2000
LIPOBLASTOMA OF THE NECK
4. Jaffe RH: Recurrent lipomatous tumors of the groin: Liposarcoma and lipoma pseudomyxomatodes. AMA Arch Pathol 1:381-387, 1926 5. Vellious F, Baez J, Shumaker HB: Lipoblastomatosis: A tumor of fetal fat different from hibernoma: Report of a case with observations of the embryogenesis of human adipose tissue. Am J Pathol 34:1149-1159, 1958 6. Chung EB, Enzinger FM: Benign lipoblastomatosis. An analysis of 35 cases. Cancer 32:482-492, 1973 7. Hicks J, Dilley A, Patal D, et al: Lipoblastoma and lipoblastomatosis in infancy and childhood: Histopathologic, ultrastructural, and cytogenetic features. Ultrastruct Pathol 25:321-333, 2001 8. Stringel G, Shandling B, Mancer K, et al: Lipoblastoma in infants and children. J Pediatr Surg 17:277-281, 1982 9. Collins MH, Chatten J: Lipoblastoma/lipoblastomatosis: A clinicopathologic study of 25 tumors. Am J Surg Pathol 21:1131-1137, 1997 10. Chun YS, Kim WK, Park KW, et al: Lipoblastoma. J Pediatr Surg 36:905-907, 2001 11. Dilly AV, Patel DL, Hicks MJ, et al: Lipoblastoma:
269
Pathophysiology and surgical management. J Pediatr Surg 36:229-231, 2001 12. Arda IS, Senocak ME, Gogus S, et al: A case of benign intrascrotal lipoblastoma clinically mimicking testicular torsion and review of the literature. J Pediatr Surg 28:259-261, 1993 13. Mahour GH, Bryan BJ, Issacs H: Lipoblastoma and lipoblastomatosis—A report of six cases. Surgery 104: 577-579, 1988 14. Reiseter T, Nordshis T, Borthne A, et al: Lipoblastoma: MRI appearances of a rare paediatric soft tissue tumour. Pediatr Radiol 29:542-545, 1999 15. Park CH, Kim KI, Lim YT, et al: Ruptured giant intrathoracic lipoblastoma in a 4-month-old infant: CT and MR finding. Pediatr Radiol 30:38-40, 2000 16. Schultz E, Rosenblatt R, Mitsudo S, et al: Detection of a deep lipoblastoma by MRI and ultrasound. Pediatr Radiol 23:409-410, 1993 17. Coffin CM: Lipoblastoma: An embryonal tumor of soft tissue related to organogenesis. Semin Diagn Pathol 11:98-103, 1994
Lipoblastoma is a rare benign tumor that occurs in infancy and early childhood. This tumor commonly arises from the limbs and trunk, and involvement of the neck is extremely rare. To date, 12 cases of cervical lipoblastoma have been reported in the English literature. The most common presentation is a painless neck mass, but the compression of cervical structures results in respiratory insufficiency.1,2 Horner’s syndrome1,3 and hemiparesis.3 Magnetic resonance imaging (MRI) is particularly useful to define the extent of the lesion and to evaluate the preoperative diagnosis. Lipoblastoma is rapidly growing, and complete surgical excision is recommended; there are reported recurrences after inadequate excision. Diagnosis is determined by histopathologic findings. In this article, we describe a rare case of cervical lipoblastoma in a 1-year-old boy. Clinical manifestations, radiologic and histopathologic findings, and treatment of this lesion are discussed.
From the Department of Otorhinolaryngology, Mie University School of Medicine, Mie, Japan. Address correspondence to: Mayuko Sakaida, MD, Department of Otorhinolaryngology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 5148507, Japan. E-mail: [email protected]. © 2004 Elsevier Inc. All rights reserved. 0196-0709/$ - see front matter doi:10.1016/j.amjoto.2003.12.008 266
CASE REPORT A 1-year-old boy presented to the Department of Otorhinolaryngology, Mie University Hospital, with a history of painless swelling in the left neck for 3 months that rapidly enlarged. The patient did not have a stridor, dyspnea, or dysphagia. He had a history of cardiovascular surgery for the complete transposition of great arteries and ventricular septal defect. Physical examination revealed a huge neck mass that was smooth and soft (Fig 1). The neurologic examination was unremarkable. MRI showed a 7 ⫻ 7 cm expansive mass that extruded into the parapharyngeal and paratracheal spaces. The larynx and trachea were displaced to the right (Fig 2). Both T1weighted and T2-weighted imaging showed a lobulated fatty mass with high signal intensity, but it was hypointense to subcutaneous fat on T1-weighted images. At the operation, a 10 ⫻ 6 ⫻ 5 cm, wellcircumscribed, yellowish-white mass was completely removed. There was no invasion of any of the neck structures. Macroscopic examination revealed a well-encapsulated lobulated mass. The cut surface was mostly fat-like, but partially occupied by gray-white gelatinous tissues. Microscopically, the tumor consisted of lobulated mature adipose tissue with loose fibrous septa. Some lobes contained myxoid and immature adipose tissue, with immature stellate to spindled mesenchy-
American Journal of Otolaryngology, Vol 25, No 4 (July-August), 2004: pp 266-269
LIPOBLASTOMA OF THE NECK
267
of airways and cervical sympathetic trunk, respectively. O’Donnel et al3 reported the case with weakness of upper extremity caused by the mild compression of spinal cord. In this case, the tumor extruded into the parapharyngeal and paratracheal spaces and displaced the trachea and larynx to the other side; however, the patient had no respiratory symptom. MRI is particularly useful for the preoperative evaluation and diagnosis. Although computed tomography can show the fat-dense
Fig 1. A soft and huge mass on the left side of the neck. Figure can be viewed in color online.
mal cells and multivacuolated lipoblasts (Fig 3). The histopathologic diagnosis was lipoblastoma. The postoperative course was uneventful, and no recurrence has been noted in more than 2 years follow-up. DISCUSSION Lipoblastoma and lipoblastomatosis are rare benign tumors arising from fetal embryonal white fat. In 1926, Jaffe4 used the term lipoblastoma to describe a tumor of immature fat cells, and, in 1958, Vellious et al5 described lipoblastomatosis as benign neoplasm of fetal fat tissue of the postnatal period. Chung and Enzinger,6 in 1973, suggested the term benign lipoblastoma to be used for the circumscribed type, and the term lipoblastomatosis for the diffuse multicentric type of this neoplasm. The patients’ age ranged from 5 days to 18 years,6-10 with more than 80% cases occurring before the age of 3 years.6,11 They commonly arise from extremities (30%70%) and trunk (20%-50%), and involvement of the neck is rare (10%-15%).6-10,12 To date, 169 cases of lipoblastoma and lipoblastomatosis (34 cervical cases) have been reported in the English literature, and only 12 cases were reported to be lipoblastoma of the neck. The most common presentation of cervical lipoblastoma is a rapidly growing painless mass. Two of the 12 cases had respiratory insufficiency,1,2 and 2 other cases had Horner’s syndrome1,3 caused by the compression
Fig 2. (A) Axial and (B) sagittal MRI on T1-weighted images showing a large fatty tumor that extruded into the parapharyngeal and the paratracheal spaces. Larynx and trachea are displaced to the right.
268
Fig 3. Microscopic view showing (A, arrows) multivacuolated lipoblasts and (B, arrows) spindle-shaped, immature mesenchymal cells in a myxoid stroma (hematoxylin and eosin, ⴛ400). Figure can be viewed in color online.
mass containing the enhanced septa, MRI can suggest the histology of some component of the tumor. Lipoblastoma is mostly high-signal intensity on both T1-weighted and T2weighted images but shows lower signal intensity than mature fat tissue on T1-weighted images. The area with mature fat tissue is found as the area of high-signal intensity on T1-weighted images, and the fibrous septa are hypointense.14,16 The high-signal intensity on T2-weighted images may be caused by the rich myxoid stroma with numerous lipoblasts.14-16 None of these findings, however, are diagnostic of lipoblastoma because these findings can be noted with many benign and malignant fatty tumors, such as lipoma, hibernoma, and liposarcoma. The only definitive procedure to diagnosis is biopsy or surgical excision and pathologic proof. Histopathologically, lipoblastoma consists of lobulated adipose tissue with fibrous septa
SAKAIDA ET AL
and possesses eosinophilic mucinous to myxoid stroma with immature adipocytes, which include poorly differentiated stellate to spindled mesenchymal cells, multivacuolated lipoblasts, and nearly mature adipocytes.7 Pleomorphism and cytologic atypia are lacking, but mitotic activity may be seen. Other fat tissue tumors also have histologic similarities to lipoblastoma. Lipoma, fibrolipoma, and angiolipoma have lobules with fibrous septa but lack of lipoblasts.17 Hibernoma also displays a lobular pattern but consists entirely of brown fat cells with eosinophilic, granular cytoplasm.17 Myxoid liposarcoma has lobulation and myxoid stroma, but it may be rare in children, mainly after 15 years old, and there is a significant degree of cellular pleomorphism with nuclear atypia, atypical multivacuolated lipoblasts, and atypical mitotic figures.7,17 Recent cytogenetic analysis revealed specific chromosomal abnormalities in adipose tissue tumors. In the case of lipoblastoma, cytogenetic breakpoint abnormalities occur consistently in the chromosome 8q11-q13.7 Other adipose tissue tumors may also have characteristic cytogenetic abnormalities; lipoma shows variable translocations in chromosome 12. Myxoid liposarcoma is characterized by the translocation t(12;16)(q13;p11), and hibernoma shows the rearrangement in chromosome 11q13. In this case, we did not examine the chromosomal analysis; however, this procedure will be helpful for the diagnosis of these adipose tissue tumors. Complete surgical excision is the treatment of choice. Local recurrences are reported in 14% to 25%7 of the lipoblastoma and lipoblastomatosis cases, and they have been attributable to an incomplete excision. In cases of lipoblastoma, recurrence is rare and no recurrence has been reported in the 12 cases with cervical lipoblastoma. REFERENCES 1. Gammelgaard N, Jorgensen K, Lund C, et al: Benign Lipoblastoma in the neck causing respiratory insufficiency. Laryngoscope 93:935-937, 1983 2. Rasmusen LS, Kirkegaad J, Kaasbol M: Intermittent airway obstruction in a child caused by a cervical lipoblastoma. Acta Anaesthesiol Scand 41:945-946, 1997 3. O’Donnel KA, Caty MG, Allen IE, et al: Lipoblastoma: Better termed infantile lipoma? Pediatr Surg Int 16:458-461, 2000
LIPOBLASTOMA OF THE NECK
4. Jaffe RH: Recurrent lipomatous tumors of the groin: Liposarcoma and lipoma pseudomyxomatodes. AMA Arch Pathol 1:381-387, 1926 5. Vellious F, Baez J, Shumaker HB: Lipoblastomatosis: A tumor of fetal fat different from hibernoma: Report of a case with observations of the embryogenesis of human adipose tissue. Am J Pathol 34:1149-1159, 1958 6. Chung EB, Enzinger FM: Benign lipoblastomatosis. An analysis of 35 cases. Cancer 32:482-492, 1973 7. Hicks J, Dilley A, Patal D, et al: Lipoblastoma and lipoblastomatosis in infancy and childhood: Histopathologic, ultrastructural, and cytogenetic features. Ultrastruct Pathol 25:321-333, 2001 8. Stringel G, Shandling B, Mancer K, et al: Lipoblastoma in infants and children. J Pediatr Surg 17:277-281, 1982 9. Collins MH, Chatten J: Lipoblastoma/lipoblastomatosis: A clinicopathologic study of 25 tumors. Am J Surg Pathol 21:1131-1137, 1997 10. Chun YS, Kim WK, Park KW, et al: Lipoblastoma. J Pediatr Surg 36:905-907, 2001 11. Dilly AV, Patel DL, Hicks MJ, et al: Lipoblastoma:
269
Pathophysiology and surgical management. J Pediatr Surg 36:229-231, 2001 12. Arda IS, Senocak ME, Gogus S, et al: A case of benign intrascrotal lipoblastoma clinically mimicking testicular torsion and review of the literature. J Pediatr Surg 28:259-261, 1993 13. Mahour GH, Bryan BJ, Issacs H: Lipoblastoma and lipoblastomatosis—A report of six cases. Surgery 104: 577-579, 1988 14. Reiseter T, Nordshis T, Borthne A, et al: Lipoblastoma: MRI appearances of a rare paediatric soft tissue tumour. Pediatr Radiol 29:542-545, 1999 15. Park CH, Kim KI, Lim YT, et al: Ruptured giant intrathoracic lipoblastoma in a 4-month-old infant: CT and MR finding. Pediatr Radiol 30:38-40, 2000 16. Schultz E, Rosenblatt R, Mitsudo S, et al: Detection of a deep lipoblastoma by MRI and ultrasound. Pediatr Radiol 23:409-410, 1993 17. Coffin CM: Lipoblastoma: An embryonal tumor of soft tissue related to organogenesis. Semin Diagn Pathol 11:98-103, 1994