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Journal of Pediatric Surgery (2007) 42, 2120–2122

Transmural intrathoracic lipoma with intraspinal extensionVishesh Jaina, Arbinder K. Singala, Arun K. Guptab, Veereshwar Bhatnagara,⁎

aDepartment of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi 110029, IndiabDepartment of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi 110029, India

Received 11 June 2007; revised 1 August 2007; accepted 9 August 2007

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Index words:Intrathoracic lipoma;Chest wall defect;Intraspinal extension

Abstract A rare case of transmural dumbbell intrathoracic lipoma with intraspinal extension is reported.Preoperative diagnosis was possible with a computed tomographic scan and fine-needle aspirationcytology. Complete excision was curative. The chest wall defect was repaired with Prolene mesh. Onlyone similar case has been previously reported in the English literature.© 2007 Elsevier Inc. All rights reserved.

Lipomas are ubiquitous and can occur anywhere in thebody. Thoracic lipomas are uncommon benign lesions in thepediatric age group; transmural dumbbell lesions are evenmore infrequent, and those with spinal extension areextremely rare. Radiologic investigations help in makingthe diagnosis but cannot rule out malignancy. Completesurgical excision is curative and provides histologic certaintyabout the benign nature of the tumor.

1. Case report

A 4-year-old girl presented with a painless, graduallyenlarging swelling in the right upper back. She hadrecurrent episodes of nonproductive cough with fever, butthere were no neurologic complaints. The general examina-tion revealed a 6 × 4–cm soft swelling in the rightparaspinal region, medial to the scapula and extendingpartly under the scapula (Fig. 1). Cough impulse was

⁎ Corresponding author.E-mail address: veereshwarb@hotmail.com (V. Bhatnagar).

022-3468/$ – see front matter © 2007 Elsevier Inc. All rights reserved.oi:10.1016/j.jpedsurg.2007.08.045

present. Air entry was decreased on the right side.Neurologic examination result was normal. Plain chest x-ray revealed a soft tissue mass lifting up the scapula,widening of the third intercostal space, and extension intothe right hemithorax (Fig. 2). There was no calcification inthe mass and no erosion of ribs. Noncontrast computedtomographic scan showed a 7 × 6 × 6–cm fat-density lesionin the right subscapular region extending into the rightthorax through the third intercostal space, displacing themediastinum to the left with partial atelectasis of the rightupper lobe (Fig. 3). Small intraspinal extension at the levelof the third dorsal lumbar vertebra was noted to be causingwidening of intervertebral foramen with extension into theextradural space. Fine-needle aspiration cytology revealedfibroadipose tissue in a background of inflammatoryinfiltrate, suggestive of lipoma. The patient was exploredthrough a right posterolateral thoracotomy via the bed of thefourth rib, revealing a huge lipomatous mass, partlyextrathoracic, extending into the thorax through thirdintercostal space and into the spinal canal via the thirdintervertebral foramina (Fig. 4). The mass was well defined,with no invasion into the surrounding structures. The masswas completely resected along with the intraspinal exten-sion. The defect in between the splayed ribs was repaired bya Prolene mesh. Histopathologic examination demonstrated

ig. 3 Noncontrast computed tomographic scan showing trans-ural hourglass intrathoracic lipoma with intraspinal extension ate level of the third thoracic vertebra.

Fig. 1 Right paraspinal swelling extending beneath theright scapula.

2121Intraspinal extension in transmural thoracic lipoma

a lipoma. The patient had an uneventful recovery andremains asymptomatic on follow-up.

2. Discussion

Intrathoracic lipomas are uncommon benign lesions andonly rarely have been described in the pediatric age group.These tumors are usually single and involve both sides ofthorax with same frequency [1-3].

The most widely used classification is by Keeley andVana [4] and Williams and Parsons [5]. They dividedintrathoracic lipoma in 2 classes: (1) intrathoracic, orcompletely within the thoracic cavity, and (2) hourglass ordumbbell types that have both intra-and extrathoraciclesions. These are further divided into (i) cervicomediastinaltype, which passes through thoracic inlet, and (ii) transmuraltype, which passes through intercostal space and rarelythrough the sternum.

Fig. 2 Chest x-ray postero-anterior view showing a soft tissuemass extending into the right hemithorax with widening of the thirdintercostal space.

Fmth

Intraspinal extension of a dumbbell lipoma has been rarelydescribed—only one case of a transmural intrathoraciclipoma with intraspinal extension in a pediatric patient hasbeen reported [6]. A cervicomediastinal dumbbell lipomawith intraspinal extension in a pediatric patient has also beenreported [7].

These neoplasms are slow growing and may reach greatproportions without producing symptoms. The most com-mon symptom is a nonproductive cough and a feeling ofpressure at the site of the tumor. The cervicomediastinalgroup is most likely to give early symptoms, even with smalltumors. When a tumor produces massive collapse of the lungor encroaches upon a main bronchus, dyspnea appears. Thisdyspnea can be of such severity as to cause death [8].Malignant degeneration into liposarcoma is of sometheoretical concern; however, there are no reports of thishaving occurred.

Computed tomographic scan achieves identification ofthe fatty tumor component, characterized by low-gradedensity, but it does not distinguish between various adipose

ig. 4 Operative view of a huge lipomatous dumbbell massxtending into the thorax through the third intercostal space.

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2122 V. Jain et al.

tumors. However, infiltration of surrounding structures ratherthan displacement may suggest liposarcoma, and presence of afibrovascular network during contrast enhancement maysuggest lipoblastoma. Magnetic resonance imaging is occa-sionally indicated if there is a large intraspinal component or ifthere are symptoms and signs of nerve root/spinal cordcompression. In the case under review, magnetic resonanceimaging was not expected to provide further information.Definitive diagnosis can only be achieved by pathologicexamination, which must differentiate between lipoma,lipoblastoma, hibernoma, and liposarcoma; the last 2 arevery rare in childhood. In general, the diagnosis is notestablished until surgical resection has been performed.

Although these tumors are benign, resection is necessaryto unequivocally establish the diagnosis, alleviate symptoms,and prevent local recurrence. Aggressive evaluation andcomplete surgical excision have been recommended for theseunusual lesions. Complete surgical removal, particularly ofthe intraspinal component, may be challenging. In general, aknuckle of tissue entering the vertebral foramina, as in thecase under review, usually does not need any complexsurgical approach and can be excised via the thoracotomy.But if the intraspinal component of the tumor is large,infiltrative, or causing neural compression, then a priorneurosurgical approach via a laminectomy may be indicatedeither as a separate intervention or under the same anesthesia.

The other challenge is in the reconstruction of the chestwall defect, which is necessary for the stability andphysiologic kinetics of the chest wall. Simple approximationof the ribs may be sufficient if the defect is small and ifthe ribs are not deformed. However, if the defect is large,as in the case under review, then fascial or rib grafts,synthetic mesh, or other prosthetic materials can be used forchest wall reconstruction.

References

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with rib erosion in an infant. Radiology 1972;104:111-2.[3] Johansson L, Soederlund S. Intrathoracic lipoma. Acta Chir Scand

1963;126:558-65.[4] Keeley JL, Vana AJ. Collective reviews: lipomas of the mediastinum—

1940-1955. Int Abst Surg 1955;103:313-22.[5] Williams WT, Parsons WH. Intrathoracic lipomas. J Thorac Surg 1957;

33:785-90.[6] Maier HC. Extradural and intrathoracic lipoma causing spinal cord

compression. Successful treatment by surgical excision. JAMA 1962;181:610-2.

[7] Waldehausen JHT, Rodgers BM, Silen ML. Pediatric intrathoraciclipoma. Pediatr Surg Int 1993;8:248-50.

[8] Leopold RS. A case of massive lipoma of the mediastinum. Arch IntMed 1920;26:274-8.