Case Report
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jul 6, 2019; 7(13): 1677-1685
Published online Jul 6, 2019. doi: 10.12998/wjcc.v7.i13.1677
Multimodality-imaging manifestations of primary renal-allograft synovial sarcoma: First case report and literature review
Rui-Fang Xu, En-Hui He, Zhan-Xiong Yi, Jun Lin, Yan-Ning Zhang, Lin-Xue Qian
Rui-Fang Xu, En-Hui He, Zhan-Xiong Yi, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
Jun Lin, Department of Urological Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
Yan-Ning Zhang, Department of Pathology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
Author contributions: Xu RF did all the traditional ultrasound and contrast enhanced ultrasonography examinations for the patient and contributed to manuscript drafting; He EH reviewed and interpreted the contrast enhanced ultrasonography imaging of the patient; Yi ZX viewed the CT imaging of the patient; Lin J was the patient’s surgeon; Zhang YN performed the pathological and immunohistochemical examinations and made the final diagnosis for the patient; Qian LX was responsible for the revision of the manuscript; all authors issued final approval for the version to be submitted.
Supported by Funding from the Beijing Municipal Administration of Hospitals’ Ascent Plan, No. DFL 20180102.
Informed consent statement: Informed consent was obtained from the patient in the study.
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 (2013), and the manuscript was prepared and revised according to the CARE Checklist (2016).
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/
Corresponding author: Lin-Xue Qian, MD, PhD, Chief Doctor, Director, Professor, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, No. 95, Yongan Road, Xicheng District, Beijing 100050, China. qianlinxue@outlook.com
Telephone: +86-13311100999 Fax: +86-010-63139087
Received: February 14, 2019
Peer-review started: February 15, 2019
First decision: Mach 14, 2019
Revised: April 30, 2019
Accepted: May 10, 2019
Article in press: May 11, 2019
Published online: July 6, 2019
Processing time: 142 Days and 8 Hours
Abstract
BACKGROUND

Primary renal synovial sarcoma (PRSS) is an extremely rare tumor with a poor prognosis. Its imaging and immunohistochemical characteristics may overlap with other renal tumors, which renders its early diagnosis in a dilemma. The diagnosis of primary renal synovial sarcoma requires histopathology and the confirmation of SYT-SSX gene fusion using molecular techniques. Cases of primary renal synovial sarcoma have been previously reported in the literature. However, to our knowledge, primary renal allograft synovial sarcoma was never described.

CASE SUMMARY

A 43-year-old male patient who underwent kidney transplantation 9 months ago came to our hospital for regular follow-up. Traditional ultrasonography revealed multiple hypo-echo neoplasms in the renal allograft. Contrast-enhanced computed tomography (CECT) showed slightly hyper-density masses with slow homogeneous enhancement. Ultrasound-guided biopsy was conducted for accurate pathological diagnosis. The neoplasms were diagnosed as synovial sarcoma by pathological, immunohistochemical, and genetic analyses. Positron emission tomography/CT showed no evidence of metastasis. At approximately one week post biopsy, contrast-enhanced ultrasound was conducted to eliminate active hemorrhage. One month later, CECT showed that the biggest neoplasm grew from 3.3 cm to 5.7 cm in diameter. Parametric imaging was conducted with SonoLiver CAP to conduct further quantitative analysis, which showed that the enhancement pattern was heterogeneous hyper-vascular enhancement. Radical surgical resection of the whole renal allograft and ureter was conducted without additional adjuvant chemotherapy or external radiotherapy. Anlotinib was chosen for targeted therapy with a good response.

CONCLUSION

We propose multimodality imaging for accurate diagnosis of renal allograft synovial sarcoma especially when it is formed by spindle-shaped cells.

Keywords: Renal allograft; Multimodality-imaging; Renal synovial sarcoma; Ultrasonography; Computed tomography; Case report

Core tip: Primary renal synovial sarcoma is an extremely rare tumor with a poor prognosis. We present the multimodality imaging characteristics of primary renal allograft synovial sarcoma in a 43-year-old male patient, which manifested as new hypo-echo solid neoplasms on ultrasonography or cystic-like neoplasms on contrast-enhanced computed tomography. After an accurate diagnosis was made, radical allograft nephrectomy was done without additional adjuvant chemotherapy or external radiotherapy. Anlotinib was chosen for targeted therapy. This case highlights the importance of multimodality imaging for early accurate diagnosis of renal allograft synovial sarcoma, especially when it is formed by spindle-shaped cells.