title: Synovial sarcoma in knee joint, mimicking low-grade sarcoma confirmed by molecular detection of SYT gene split.
abstract: A 10-year-old boy underwent arthroscopic curettage for an intra-articular mass in knee joint. The tumor was diagnosed as low-grade fibrous sarcoma. Five years later, the patient presented with a recurrent tumor. The patient underwent a marginal excision with knee joint preservation and without adjuvant therapy. Two years after the last surgery, the patient is thriving with no evidence of recurrent or metastatic disease. The final diagnosis was synovial sarcoma confirmed via a SYT gene split performed with fluorescent in situ hybridization (FISH), although the tumor appeared as a low-grade fibrous type in a hematoxylin-eosin section. The first curetted specimen was also confirmed to bear a SYT gene split. Synovial sarcoma has been conventionally recognized as a high-grade sarcoma. Our patient had a tumor that exhibited the characteristics of both a histologically and clinically low-grade tumor. From the present case, we consider that low-grade variants of synovial sarcoma do exist although their existence remains controversial.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan hiroaki030301@yahoo.co.jp.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kimura
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Yamamoto
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors.forename: Hideji
authors.initials: H
authors.lastname: Nishida
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Takeuchi
authors.affiliation: Department of Pathology and Laboratory Medicine, Kanazawa Medical University, Ishikawa, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nojima
authors.affiliation: Section of Diagnostic Pathology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Ikeda
authors.affiliation: Section of Diagnostic Pathology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Seiko
authors.initials: S
authors.lastname: Sawada-Kitamura
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsuchiya
mesh_terms: D017398:Alternative Splicing; D014408:Biomarkers, Tumor / Q000235:genetics*; D002648:Child; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007719:Knee Joint / Q000378:metabolism / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics*; D013584:Sarcoma, Synovial / Q000175:diagnosis* / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; C093961:SS18 protein, human
keywords: SYT gene split; Synovial sarcoma; intra-articular tumor