Journal List > Korean J Gastroenterol > v.62(4) > 1007150

Korean J Gastroenterol. 2013 Oct;62(4):248-252. Korean.
Published online October 23, 2013.
Copyright © 2013 The Korean Society of Gastroenterology
A Case of Pleomorphic Liposarcoma in a Patient with Crohn's Disease Taking Azathioprine
Soo Min Ahn, Seong O Suh, Yu Mi Oh, Chang Yong Yun, Hyoung Hun Sim, Chae A Park, Cheol Min Song,1 and Ji Yoon Bae2
Department of Internal Medicine, National Police Hospital, Seoul, Korea.
1Department of Thoracic and Cardiovascular Surgery, National Police Hospital, Seoul, Korea.
2Department of Pathology, National Police Hospital, Seoul, Korea.

Correspondence to: Seong O Suh, Division of Gastroenterology, Department of Internal Medicine, National Police Hospital, 123 Songi-ro, Songpa-gu, Seoul 138-708, Korea. Tel: +82-2-3400-1224, Fax: +82-2-3400-1125, Email:
Received February 12, 2013; Revised April 08, 2013; Accepted April 09, 2013.

This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


Azathioprine is frequently used for the treatment of inflammatory bowel diseases (IBD) such as Crohn's disease and ulcerative colitis. Lymphomas, squamous cell carcinomas, and undifferentiated pleomorphic sarcomas have been reported among patients receiving azathioprine therapy. Herein, we report a case of pleomorphic liposarcoma of chest wall which occurred in a 44-year-old man with Crohn's disease taking azathioprine. He was diagnosed with Crohn's disease 3 years ago after suffering from abdominal pain and hematochezia for 12 years. He had been taking 50 mg of azathioprine per day for 23 months when he visited the thoracic and cardiovascular surgery clinic due to right chest palpable mass that had rapidly grown during the past 2 months. Excisional biopsy was performed and the mass was diagnosed as pleomorphic liposarcoma. Therefore, he underwent radical excision of the right chest wall mass, which measured 11.0×6.5 cm in size. He is scheduled to receive radiation therapy and chemotherapy.

Keywords: Crohn disease; Azathioprine; Liposarcoma


Fig. 1
(A) Initial colonoscopy shows ulcer scars with several pseudopolyps and ileocecal valve deformity. (B) Initial CT enterogram demonstrates multifocal enhancing wall thickening of the small bowel and ascending colon with fatty infiltration (white arrows). (C) Small bowel series shows multifocal strictures in the ileal loop (black arrows).
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Fig. 2
About 8.0×6.2 cm sized heterogenous enhancing soft tissue mass (white arrow) is noted at far lateral side of right pectoralis muscle on chest CT scan.
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Fig. 3
18F-fluorodeoxyglucose (FDG) PET/CT findings. (A) PET/CT and (B) PET image reveal increased FDG uptake (A: white arrow, B: black arrow; standardized uptake value of 12.6) at the lateral aspect of right pectoralis muscle with no other abnormal metabolic lesions.
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Fig. 4
Microscopic findings (H&E). (A) Tumor cells infiltrating adjacent skeletal muscles (black arrow; ×10). (B) There are many pleomorphic lipoblasts (black arrows) with atypical mitosis (white arrows) (×200). (C) There are hyperchromatic nuclei cells (black arrows) in the myxoid matrix (×200).
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Fig. 5
Immunohistochemical staining findings (×200). It shows positive staining for vimentin (A) and p53 (B).
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Fig. 6
Gross specimen. The well circumscribed mass measured 11.0×6.5 cm in size.
Click for larger image


Financial support: None.

Conflict of interest: None.

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