대한흉부영상의학회 Weekly Chest Cases

Case No : 389 Date 2005-04-09

Courtesy of Jeong Joo Woo, M.D. / Eulji Hospital, Seoul, Korea
Age/Sex 58 / F
Chief ComplaintIncidental abnormality on chest radiograph

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Diagnosis With Brief Discussion

Diagnosis: Angiolipoma of the mediastinum
Radiologic Findings: Chest PA radiograph shows a paracardiac mass. Unenhanced CT scan(7.5mm thickness) shows a mediastinal mass just lateral to IVC.with homogeneous soft tissue density (HU 20). Contrast-enhanced CT scan(5mm thickness) and coronal reformat image(1.5mm thickness) show an highly enhanced mass mixed with fatty region.
Photomicrograph shows a combination of mature adipose tissue and multiple small blood vessels (H & E).
Brief Review: Angiolipoma is a rare benign soft tissue tumor, an unusual variant of lipoma, consisting of fatty and vascular components.

Lin et al.(1) defined the characteristics of the tumor as follows: (a) gross evidence of tumor formation with or without capsule, (b) microscopic evidence of a tumor population of at least 50% mature lipocytes, (c) microscopic evidence of angiomatous proliferation inside the tumor.

Angiolipomas account for 5-17% of all lipomas. They are located mainly in the subcutis of the trunk or extremities. Uncommon locations cited in the literature have included the orbit, breast, parotid gland, palate, rib, mandible, mediastinum, intramedullary and epidural spine, and brain. Mediastinal angiolipoma is very rare and several cases of posterior mediastinal angiolipoma were only reported.

In this case, the mass exhibited homogeneous soft tissue density on unenhanced CT scans, and fatty component was only detected on enhanced axial scan and coronal thin reformat image. The raito of adipose to vascular tissue found in angiolipomas varies, ranging from a neoplasm that is predominantly lipomatous with a small angiomatous focus, to one in which dense vascular and stromal elements have replaced most of the fat(2). The differential diagnosis in this case included mediastinal hemangioma, Castleman’s disease without considering fatty tumor. Liposarcoma should be differentiated as considering fatty tumor.
References: 1. Lin JJ, Lin F. Two entities in angiolipoma: a study of 459 cases of lipoma with a review of the literature on infiltrating angiolipoma. Cancer 1974;34:720-727

2. Weil A, Donovan RC, Tampieri D, Melanson D, Ethier R. Spnal angiolipomas: CT and MR aspects. J Comput Assist Tomogr 1991;15:83-85

3. Choi J-Y, Goo JM, Chung MI, Kim H-C, Im J-G. Angiolipoma of the posterior mediastinum with extension into the spinal canal:A case report. KJR 2000;1(4):212-214
Keywords: Mediastinum, Benign tumor,

No. of Applicants : 32

▶ Correct Answer : 2/32, 6.3%

- Ev. Krkhs. Hubertus, Berlin, Germany Michael Weber
- Monaldi Hospital, Naples, Italy Gaetano Rea

▶ Semi-Correct Answer : 18/32, 56.3%

- Annemasse, Polyclinique de Savoie, France Gay-Depassier Philippe
- ASL BOLOGNA Maggiore Hospital, Bologna, Italy Marcellino Burzi
- Busan Veterans Hospital, Korea Suhku Huh
- CIM Saint Dizier, France JC Leclerc
- Dong-A University Hospital, Korea Ki-Nam Lee
- Hangang SacredHeart Hospital, Korea Eil Seong Lee
- Hanyang University Hospital, Seoul, Korea Yo Won Choi
- Homs National Hospital, Homs, Syria Rami Abou Zalaf
- Incheon Sarang Hospital, Korea Jung Hee Kim
- Jinju Jeil Hospital, Korea Hyung-Gon Lee
- Kyunghee University Hospital, Seoul, Korea Su Youn Sim
- Max Hospital, Delhi, India Vickrant Malhotra
- Ondokuz Mayis University, Samsun, Turkey Cetin Celenk
- Ping Tung Christian Hospital,Taiwan Jun-Jun Yeh
- Radiologie Guiton, La Rochelle, France Denis Chabassiere
- Samsung Medical Center, Seoul, Korea Ha Young Kim
- Seoul National University Hospital, Korea Dae Sik Kim
- Social Security Hospital, Ankara, Turkey Meric Tuzun

대한흉부영상의학회 Korean Society of Thoracic Radiology

Archive of Old Cases

Case No : 389 Date 2005-04-09

Discussion

No. of Applicants : 32