title: Primary intrathoracic synovial sarcoma: a clinicopathologic study of 40 t(X;18)-positive cases from the French Sarcoma Group and the Mesopath Group.
abstract: Synovial sarcoma (SS), an aggressive neoplasm accounting for up to 14% of soft tissue sarcomas, was recently recognized as a primary tumor in the lung and pleura. SS is characterized by the chromosomal translocation t(X;18)(SYT-SSX) found in more than 95% of the tumors. We report a cooperative study from the French Sarcoma Group and the Mesopath Group on 40 t(X;18)(SYT-SSX)-positive primary intrathoracic SS. There were 22 males and 18 females, whose age ranged from 16 to 79 years (median, 47 years). Neoplasms were mostly circumscribed and of large size (median, 7.5 cm; range, 2-16 cm). Thirty-nine tumors were monophasic SS, including 24 (60%) monophasic fibrous and 15 (37.5%) poorly differentiated cases, and one lesion was a biphasic SS. A larger proportion of poorly differentiated tumors were observed among intrathoracic SS as compared with soft tissue SS. Immunohistochemically, 90% of the cases reacted with at least one epithelial marker. CD34 was focally expressed in 3 cases. SYT-SSX1 fusion transcripts were detected in 22 cases (56.4%) and SYT-SSX2 fusion transcripts in 17 cases. Median and 5-year disease-specific survival in 33 patients was 50 months and 31.6%. Median and 5-year disease-free survival was 24 months and 20.9%. Patient sex, age, tumor size, histologic subtype, grade, and SYS-SSX fusion type had no significant impact on outcome. In conclusion, intrathoracic SS are rare but aggressive tumors with poor prognosis. In this unusual location, the detection of SYT-SSX fusion transcripts is a valuable diagnostic adjunct.
authors.affiliation: From the Department of Pathology, Hôpital Haut-Lévêque, Pessac, France.
authors.forename: Hugues
authors.initials: H
authors.lastname: Bégueret
authors.forename: Françoise
authors.initials: F
authors.lastname: Galateau-Salle
authors.forename: Louis
authors.initials: L
authors.lastname: Guillou
authors.forename: Bruno
authors.initials: B
authors.lastname: Chetaille
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Brambilla
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Vignaud
authors.forename: Philippe
authors.initials: P
authors.lastname: Terrier
authors.forename: Odile
authors.initials: O
authors.lastname: Groussard
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Coindre
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D002887:Chromosomes, Human, Pair 18; D041321:Chromosomes, Human, X; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000032:analysis; D013584:Sarcoma, Synovial / Q000737:chemistry / Q000235:genetics / Q000556:secondary*; D012983:Soft Tissue Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology*; D013899:Thoracic Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology*; D014178:Translocation, Genetic
chemical_list: D014408:Biomarkers, Tumor; D015514:Oncogene Proteins, Fusion; C116512:SYT-SSX fusion protein