Primary pulmonary myxoid sarcoma:a clinicopathologic analysis and review of literature

LI Yang; GUO Kun-liang; YU Zhao-xia; HUANG Xian; HU Quan-quan; XUAN Lan-lan

doi:10.3969/j.issn.1007-8096.2025.02.008

Abstract：Objective To investigate the clinicopathological features of primary pulmonary myxoid sarcoma(PPMS).Methods Three patients with primary pulmonary myxoid sarcoma(2 cases in Anqing Municipal Hospital and 1 case in Anqing First People's Hospital)were collected from March 2015 to March 2024.The clinicopathological features,immunophenotype,molecular genetic characteristics,follow-up treatment and prognosis were analyzed,and the literature was systematically reviewed.Results Three patients were enrolled in this study,including 1 male patient and 2 female patients,with an age range of 24 to 72 years.Two cases showed no clinical symptoms,but lung masses were found during physical examination.One case presented with cough and blood in sputum without obvious cause.Two cases of tumors were located in the upper lobe of the right lung,and one case was located in the lower lobe of the right lung.Two cases of tumors were closely related to the bronchus,while one case was unrelated to the bronchus and closely attached to the pleura.Microscopically,the tumor was multinodular.Polygonal or short spindle cells arranged in a network or cord like pattern within myxoid stroma.Tumors were immunoreactive for Vimentin(3/3),EMA(2/3),S-100(2/3),SMA(1/3).Ki-67 positive index was 3％-15％.Two cases were shown to harbor EWSR1 gene rearrangement by FISH.One case had EWSR1-CREB1 gene fusion by NGS.One patient underwent right low lobectomy,and 2 patients underwent right wedge resection.All patients were disease-free after 5-112 months.Conclusion PPMS is a rare sarcoma with low-grade malignant potential.The diagnosis of PPMS depends mainly on the location and histopathological features of PPMS.EWSR1 gene rearrangement is important for the diagnosis of PPMS.