Case Report
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Sep 26, 2020; 8(18): 4207-4214
Published online Sep 26, 2020. doi: 10.12998/wjcc.v8.i18.4207
TFE3-expressing malignant perivascular epithelioid cell tumor of the mesentery: A case report and review of literature
Nah Ihm Kim, Ji Shin Lee, Yoo Duk Choi, U Chul Ju, Jong Hee Nam
Nah Ihm Kim, Yoo Duk Choi, Jong Hee Nam, Department of Pathology, Chonnam National University Hospital and Medical School, Gwangju 61469, South Korea
Ji Shin Lee, Department of Pathology, Chonnam National University Hwasun Hospital and Medical School, Hwasun 58128, South Korea
U Chul Ju, Department of Obstetrics and Gynecology, Chonnam National University Hwasun Hospital and Medical School, Hwasun 58128, South Korea
Author contributions: Kim NI and Nam JH are pathologists that participated in the concept of the study, reviewed the literature, interpreted the H&E slides, and immunohistochemistry slides; Lee JS and Choi YD, as pathologists, contributed to drafting of the manuscript; Ju UC is a gynecological surgeon that performed the operation and was responsible for patient care; all authors read and approved the final manuscript.
Informed consent statement: Written informed consent was obtained from the patient for publication of this case report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Jong Hee Nam, MD, PhD, Professor, Department of Pathology, Chonnam National University Hospital and Medical School, 42 Jebong-ro, Gwangju 61469, South Korea. jhnam@chonnam.ac.kr
Received: April 14, 2020
Peer-review started: April 14, 2020
First decision: July 25, 2020
Revised: July 30, 2020
Accepted: August 25, 2020
Article in press: August 25, 2020
Published online: September 26, 2020
Processing time: 160 Days and 19.9 Hours
Abstract
BACKGROUND

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor that exhibits an epithelioid and spindle cell morphology. The tumor is characterized by immunoreactivity for melanocytic and myogenic markers but can be misdiagnosed as more common tumors with similar characteristics, including gastrointestinal stroma tumors or leiomyosarcomas. Recently, a subset of PEComas has been reported to harbor a transcription factor binding to TFE3 fusion. Herein, we report a rare case of TFE3-expressing malignant PEComa arising from the mesentery.

CASE SUMMARY

A 50-year-old woman presented with abdominal discomfort for 3 months. Results of laboratory tests were all within the normal ranges, and the patient had no notable medical history. Magnetic resonance imaging revealed a large tumor on the right side of the pelvic floor, which was originally suspected to be a primary ovarian tumor. However, during surgery, the tumor was revealed to have originated from the mesentery. Histologically, the tumor was composed of bundles of spindle cells and sheets of epithelioid cells. Extensive coagulative necrosis and numerous mitotic figures were observed. Immunohistochemistry revealed that the tumor cells were positive for smooth muscle actin, HMB-45, and TFE3 expression. Tumor involvement of the rectal serosa was identified, leading to a final diagnosis of malignant PEComa of the mesentery. Surgical resection was followed by adjuvant chemotherapy. No recurrence or metastasis was observed over a 6-month follow-up period.

CONCLUSION

Malignant PEComa of the mesentery is extremely rare and should be distinguished from morphological mimics through differential diagnosis and immunohistochemistry.

Keywords: Perivascular epithelioid cell tumor; TFE3; Differential diagnosis; Mesentery; Histology; Case report

Core Tip: Primary mesenchymal tumors originating from the mesentery are rare and can only be diagnosed histologically. Broad differential diagnoses and immunohistochemical analyses are required along with consideration of perivascular epithelioid cell tumor among differential diagnoses.