Case Report
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. May 16, 2018; 6(5): 88-93
Published online May 16, 2018. doi: 10.12998/wjcc.v6.i5.88
Magnetic resonance imaging findings for differential diagnosis of perianal plexiform schwannoma: Case report and review of the literature
Xue-Liang Sun, Ke Wen, Zhi-Zhong Xu, Xiao-Peng Wang
Xue-Liang Sun, Ke Wen, Zhi-Zhong Xu, Xiao-Peng Wang, Department of Colorectal Surgery, the Suzhou Affiliated Hospital of Nanjing University of Chinese Medicine, Suzhou 215000, Jiangsu Province, China
Author contributions: Sun XL designed the study and wrote the manuscript; Sun XL, Wang XP, and Wen K performed the operation; Sun XL and Xu ZZ collected the clinical data; Sun XL and Wang XP were involved in editing of the manuscript and provided financial support.
Supported by Suzhou Municipal Science and Technology Bureau, No. SYSD2017126.
Informed consent statement: The patient involved in this study gave his written informed consent authorizing use and disclosure of his protected health information.
Conflict-of-interest statement: All the authors have no conflicts of interest to declare.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Xiao-Peng Wang, MD, Professor of Surgery, Chief Doctor, Department of Colorectal Surgery, the Suzhou Affiliated Hospital of Nanjing University of Chinese Medicine, Yangsu Road No.18, Suzhou 215000, Jiangsu Province, China. wxpeng2004@163.com
Telephone: +86-512-67872805 Fax: +86-512-65225929
Received: January 15, 2018
Peer-review started: January 15, 2018
First decision: February 28, 2018
Revised: March 4, 2018
Accepted: April 1, 2018
Article in press: April 1, 2018
Published online: May 16, 2018
ARTICLE HIGHLIGHTS
Case characteristics

A nineteen-year-old male presented with a slowly growing, painless, multinodular mass on the right ischioanal fossa.

Clinical diagnosis

Clinical diagnosis was a dilemma due to no characteristic clinical feature observed.

Differential diagnosis

Magnetic resonance images and histopathologic examination were focused on to differentially diagnose plexiform schwannoma from multilocular or multinodular ancient schwannoma, liposarcoma, cavernous haemangioma and plexiform neurofibroma.

Laboratory diagnosis

There was no specific laboratory testing contributing to the diagnosis of plexiform schwannoma.

Imaging diagnosis

Magnetic resonance images showed an intratumoral nonenhanced capsule dividing the tumour into multiple homogeneously enhanced nodules.

Pathological diagnosis

Neoplasm biopsy revealed Verocay bodies, fibrous capsules, and diffuse positivity for S100 and vimentin.

Treatment

Complete resection combined with the Bascom advancement flap to suture a large defect was performed to prevent a recurrence.

Related reports

Plexiform schwannoma commonly located on head, neck, trunk and extremities was definitely diagnosed based on postoperative histopathologic examination, whereas the foci located in the perianal region was rarer and was more difficult for preoperative diagnosis without a specific nerve of origin.

Term explanation

Perianal plexiform schwannoma is an extremely rare variant of schwannoma and is difficultly diagnosed in clinic owing to the absence of a specific nerve of origin and a characteristic clinical manifestation.

Experiences and lessons

Due to a multinodular growth pattern, a suspectable plexiform schwannoma can be preoperatively confirmed according to the magnetic resonance imaging feature of an intratumoral nonenhanced capsule dividing the tumour into multiple homogeneously enhanced nodules, which contributes to plan treatment protocol.