A Case of a Retroperitoneal Schwannoma Presenting as Hypermetabolic Mass in PET-CT

Pyung Gohn Goh; Kwang Hun Ko; Eui Sik Kim; Yun Jeung Kim; Soo Youn Lee; Hee Seok Moon; Hyun Yong Jeong

doi:10.4166/kjg.2011.57.5.323

Journal List > Korean J Gastroenterol > v.57(5) > 1006814

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Goh, Ko, Kim, Kim, Lee, Moon, and Jeong: A Case of a Retroperitoneal Schwannoma Presenting as Hypermetabolic Mass in PET-CT

Case Report

Korean J Gastroenterol 2011;57(5):323-326.

Published online: 4 October 2011

DOI: https://doi.org/10.4166/kjg.2011.57.5.323

A Case of a Retroperitoneal Schwannoma Presenting as Hypermetabolic Mass in PET-CT

Pyung Gohn Goh, Kwang Hun Ko, Eui Sik Kim, Yun Jeung Kim, Soo Youn Lee, Hee Seok Moon, Hyun Yong Jeong

Department of Internal Medicine, Chungnam National University College of Medicine, Daejeon, Korea

Correspondence to: Hee Seok Moon, Department of Internal Medicine, Chungnam National University College of Medicine, 33, Munhwa-ro, Jung-gu, Daejeon 301-721, Korea. Tel: +82-42-280-7143, Fax: +82-42-257-5753, E-mail: mhs1357@hanmail.net

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Schwannoma is a benign neoplasm of the Schwann cells of the neural sheath. Most schwannomas occur in the head and neck, and extremities and rarely in the retroperitoneal space. The differentiation of a schwannoma from other malignant tumor or benign tumor is very difficult on a preoperative examination with ultrasonography, computed tomography or magnetic resonance imaging. Furthermore, the lesion with increased fluorodeoxyglucose uptake in PET-CT cannot exclude malignant tumor. Therefore, this lesion needs surgical excision and a histological examination with immunohistochemical staining. We report a case of schwannoma occuring in the retroperitoneal space that incidentally discovered by PET-CT for health-check up. Pathologic confirmation by laparoscopic excision was done.

Keywords: Schwannoma, PET-CT

References

1. Stefansson K, Wollmann R, Jerkovic M. S-100 protein in soft-tissue tumors derived from Schwann cells and melanocytes. Am J Pathol. 1982; 106:261–268.

2. Thurnher D, Quint C, Pammer J, Schima W, Knerer B, Denk DM. Dysphagia due to a large schwannoma of the oropharynx: case report and review of the literature. Arch Otolaryngol Head Neck Surg. 2002; 128:850–852.

3. Sharma SK, Koleski FC, Husain AN, Albala DM, Turk TM. Retroperitoneal schwannoma mimicking an adrenal lesion. World J Urol. 2002; 20:232–233.

4. Das Gupta TK, Brasfield RD, Strong EW, Hajdu SI. Benign solitary Schwannomas (neurilemomas). Cancer. 1969; 24:355–366.

5. Hide IG, Baudouin CJ, Murray SA, Malcolm AJ. Giant ancient schwannoma of the pelvis. Skeletal Radiol. 2000; 29:538–542.

6. Schindler OS, Dixon JH, Case P. Retroperitoneal giant schwannomas: report on two cases and review of the literature. J Orthop Surg (Hong Kong). 2002; 10:77–84.

7. Lee TY, Park JS, Sung YR, et al. A case report of neurilemmoma of the chest wall. Tuberc Respir Dis. 1997; 44:649–654.

8. Singh V, Kapoor R. Atypical presentations of benign retroperitoneal schwannoma: report of three cases with review of literature. Int Urol Nephrol. 2005; 37:547–549.

9. Funamizu N, Sasaki A, Matsumoto T, Inomata M, Shiraishi N, Kitano S. Laparoscopic resection of a retroperitoneal schwannoma behind the lesser omental sac. Surg Laparosc Endosc Percutan Tech. 2004; 14:175–177.

10. Kinoshita T, Naganuma H, Ishii K, Itoh H. CT features of retroperitoneal neurolemmoma. Eur J Radiol. 1998; 27:67–71.

11. Li Q, Gao C, Juzi JT, Hao X. Analysis of 82 cases of retroperitoneal schwannoma. ANZ J Surg. 2007; 77:237–240.

12. Kawahara E, Oda Y, Ooi A, Katsuda S, Nakanishi I, Umeda S. Expression of glial fibrillary acidic protein (GFAP) in peripheral nerve sheath tumors. A comparative study of immunoreactivity of GFAP, vimentin, S-100 protein, and neurofilament in 38 schwannomas and 18 neurofibromas. Am J Surg Pathol. 1988; 12:115–120.

13. Tokunaga T, Takeda S, Sumimura J, Maeda H. Esophageal schwannoma: report of a case. Surg Today. 2007; 37:500–502.

14. Beaulieu S, Rubin B, Djang D, Conrad E, Turcotte E, Eary JF. Positron emission tomography of schwannomas: emphasizing its potential in preoperative planning. AJR Am J Roentgenol. 2004; 182:971–974.

15. Shah N, Sibtain A, Saunders MI, Townsend E, Wong WL. High FDG uptake in a schwannoma: a PET study. J Comput Assist Tomogr. 2000; 24:55–56.

16. Girgin C, Ozkan U, Sezer A, Tugyan N. Large pelvic schwannoma causing bilateral hydronephrosis. Int J Urol. 2003; 10:616–618.

Fig. 1.

PET-CT finding. On left pelvic area, hypermetabolic mass (max SUV 3.7) (arrow) with increased FDG uptake was seen.

Fig. 2.

Abdominal CT finding (enhanced image). Focal target-like mass (about 3×2 cm) (arrow) in adjacent to left pelvic bone was seen.

Fig. 3.

Microscopic finding. It showed bundles of compact spindle cells which were surrounded by loose myxoid areas (H&E stain, ×100).

Fig. 4.

Immunohistochemical staining.(A) It showed tumor cell negative for c-kit (c-kit stain, ×200). (B) Immunohistochemical stain for S-100 protein showed that tumor cells were positively statined (brown color) (S-100 protein stain, ×200).

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