Paediatric Primary Pulmonary Synovial Sarcoma: Report of Four Cases with Unusual Histology

McKenna Megan¹, Junelyte Martyna¹, Boyle Katie¹, Doherty Declan¹, Dowling Geraldine^1,4,5 and Hartel Paul^2,3*

¹Department of Life Sciences, Atlantic Technological University, Ireland
²Department of Pathology, Sligo University Hospital, Ireland
³Department of Medicine, West Virginia University School of Medicine, USA
⁴Department of Analytical, Environmental and Forensic Science, King’s College London, UK
⁵Department of Cameron Forensic Medical Sciences, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, UK

*Corresponding Author: Hartel Paul, Professor, Department of Pathology, Sligo University Hospital, Ireland.

Received: September 10, 2025; Published: September 27, 2025

Abstract

Primary pulmonary synovial sarcoma is rare and poses a diagnostic challenge particularly when unusual histologic features are present and the pathognomonic translocation t(x;18) is negative or unknown. Four cases of paediatric primary pulmonary synovial sarcoma were evaluated noting unusual histologic features that may result in misdiagnosis. Histologically these tumors showed identical characteristics of typical adult pulmonary synovial sarcomas with dense cellularity, interlacing fascicles, hyalinized stroma, hemangiopericytoma-like vasculature, focal myxoid change, and entrapped benign pulmonary epithelium. They also showed unusual histologic features not usually seen with pulmonary synovial sarcoma but typical of other neoplasms. These included rosettes (2), papillary structures with fibrovascular cores (1), and adenomatoid change (1). Immunohistochemistry demonstrated typical expression of focal cytokeratins, vimentin, CD99, and Bcl-2, with focal immunoreactivity with smooth muscle actin. These tumours were positive with t(x;18) in 2 cases, while 2 had no tissue for testing. In conclusion, paediatric pulmonary synovial sarcoma are very similar to adult cases and awareness of focal unusual histology can prevent misdiagnosis, particularly when t(x;18) is negative or tissue is unavailable for testing.

Keywords: Paediatric; Pulmonary; Pleura; Mediastinum; Synovial Sarcoma

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Citation

Citation: Hartel Paul.,et al. “Paediatric Primary Pulmonary Synovial Sarcoma: Report of Four Cases with Unusual Histology". Acta Scientific Paediatrics 8.10 (2025): 12-16.

Copyright

Copyright: © 2025 Hartel Paul.,et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.