Interactive Cardiovascular and Thoracic Surgery 3:300-301(2004)
© 2004 European Association of Cardio-Thoracic Surgery
Intrapericardial ectopic thymic tissue
M.A. Karolczak*,
L. Bec and
W. Madry
Department of Cardiac and General Paediatric Surgery, Warsaw University Medical School, 00354 Warszawa, Dynasy 10-1, Poland
* Corresponding author. Tel.: +48-22-8265774; fax: +48-22-452-3301
makdynas{at}poczta.onet.pl
Received October 28, 2003;
received in revised form November 21, 2003;
accepted December 16, 2003
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Abstract
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Accessory intrapericardial, periaortic ectopic thymic tissue incidentally found in 2.5-year-old girl during open heart surgery is presented and discussed in detail.
Key Words: Ectopic thymic tissue; Cardiac surgery; Pericardium
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1. Introduction
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Intrapericardial ectopic thymic tissue is an uncommon finding. Misplaced thymus could be diagnosed as a cervical tumor [1–3] or intrathyroidal nodular masses [4–7] but pericardial location has been reported only in individual autopsy cases of thymoma [8,9].
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2. Case report
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A 2.5-year-old girl was referred to our institution for open heart surgery with diagnosis of perimembranous ventricular septal defect (VSD). Routine preoperative X-ray showed normal heart silhouette and echocardiographic examination revealed nothing unusual despite VSD with significant left to right shunt. On surgery, chest was open with longitudinal sternotomy and mediastinal part of large bi-lobal thymus was removed as a part of the routine. Once pericardial sack was longitudinally incised it was found that aortic root was covered by soft encapsulated thymus-like gland tissue (3x6x1 cm3; Fig. 1). The tumor was easily dissected from the aorta and pericardium. Pathologic examination revealed normal thymic structure. The cardiopulmonary bypass was instituted and VSD closed uneventfully. She was discharged at 7th day after surgery.
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3. Discussion
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Ectopic, misplaced or aberrant thymus in the neck is obviously related to disturbance of physiologic descent taking place during 8th week of gestation. Therefore, one could find unilateral, bilateral or multifocal lesions scattered from the skull basis to submandibular region. In 65% of those patients mediastinal thymic tissue is absent, whereas in additional 20% it is small or unilateral [1]. It strongly suggests the need for searching thymic tissue in the neck, i.e. in patients with DiGeorge syndrome. In other words, lack of mediastinal thymus does not necessarily mean thymic agenesis.
Intrapericardial ectopic thymus represents slightly different entity. We can speculate that the gland descended ‘too far’ sliding into or invaginating into pericardial sack. It is hard to predict whether it could be of any significance in the future. We do not dare to evaluate the chance for malignant changes but believe that the tumor should be surgically removed.
doi:10.1016/j.icvts.2003.12.008
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References
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- Bale PM, Sotelo-Avila C. Maldescent of the thymus: 34 necropsy and 10 surgical cases, including 7 thymuses medial to the mandible. Pediatr Pathol. 1993;13:181–190[Medline]
- Barrick B, O'Kell RT. Thymic cysts and remnant cervical thymus. J Pediatr Surg. 1969;4:355[CrossRef]
- Movitz D, Lum CL. Thymic cyst of the neck simulating goiter. Surgery. 1962;51:456[Medline]
- Gimm O, Krause U, Wessel H, Finke R, Dralle H. Ectopic intrathyroidal thymus diagnosed as a solid thyroid lesion: case report and review of the literature. J Pediatr Surg. 1997;32:1241–1243[CrossRef][Medline]
- Miller WT Jr., Gefter WB, Miller WT. Thymoma mimicking a thyroid mass. Radiology. 1992;184:75–76[Abstract/Free Full Text]
- Miyauchi A, Kuma K, Matsuzuka F, Matsubayashi S, Kobayashi A, Tamai H, Katayama S. Intrathyroidal epithelial thymoma: an entity distinct from squamous cell carcinoma of the thyroid. World J Surg. 1985;9:128–135[CrossRef][Medline]
- Büyükyavuz
 , Otçu S, Karnak , Akçören Z,  enocak ME. Ectopic thymic tissue as a rare and confusing entity. Eur J Pediatr Surg. 2002;12:327–329[CrossRef][Medline]
- Mirra M, Zanella M, Bussani R, Falconieri G. Intrapericardial thymoma: report of two incidental autopsy cases and review of the literature. Arch Pathol Lab Med. 1997;121(1):59–63[Medline]
- Blaker H, Dragoje S, Laissue JA, Otto HF. Pericardial involvement by thymomas. Entirely intrapericardial thymoma and a pericardial metastasis of thymoma with glomeruloid vascular proliferations. Pathol Oncol Res. 1999;5(2):160–163[CrossRef][Medline]
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Abstract
1. Introduction