title: Tenosynovial giant cell tumour (pigmented villonodular synovitis-)-like changes in periprosthetic interface membranes.
abstract: Tenosynovial giant cell tumour (TSGCT; synonym, pigmented villonodular synovitis (PVNS)) is a rare low-grade mesenchymal neoplasm of either intra-articular or extra-articular origin. The etiopathogenesis of TSGCT is still uncertain, but recent studies showed a translocation involving colony-stimulating factor 1 (CSF-1) gene in a subset of cases. Histological features mimicking TSGCT can sometimes be encountered in periprosthetic interface membranes. To investigate the frequency and morphologic spectrum of this phenomenon, we conducted a systematic analysis of 477 periprosthetic interface membranes and performed immunohistochemical analysis on a subset of lesions compared to genuine TSGCT. In 26 of 477 periprosthetic membrane samples (5 %), at least some TSGCT-like features were found and 18 cases (4 %) strongly resembled it. Wear particles were detected in 100 % of the TSGCT-like lesions but only in 63.3 % of the whole cohort of periprosthetic membranes (p value <0.001). Immunohistochemistry comparing true TSGCT and TSGCT-like membranes showed similar inflammatory infiltrates with slightly elevated CD3+/CD8+ T lymphocytes and a slightly higher proliferation index in TSGCT samples. In conclusion, TSGCT-like changes in periprosthetic membranes likely represent exuberant fibrohistiocytic inflammatory response induced by wear particles and should be distinguished from genuine (neoplastic) TSGCT. Although TSGCT and TSGCT-like periprosthetic membranes represent different entities, their comparable morphology might reflect analogous morphogenesis.
authors.affiliation: Institute of Pathology, Friedrich-Alexander-University, 91054, Erlangen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Söder
authors.affiliation: Department of Orthopaedic Surgery, Friedrich-Alexander-University, 91054, Erlangen, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Sesselmann
authors.affiliation: Institute of Pathology, Hospital of Coburg, 96450, Coburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Aigner
authors.affiliation: Department of Orthopaedics, Hospital of Rummelsberg, 90592, Schwarzenbruck, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Oehler
authors.affiliation: Institute of Pathology, Friedrich-Alexander-University, 91054, Erlangen, Germany. abbas.agaimy@uk-erlangen.de.
authors.forename: Abbas
authors.initials: A
authors.lastname: Agaimy
mesh_terms: D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000276:immunology*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology; D049109:Cell Proliferation / Q000502:physiology; D005260:Female; D005870:Giant Cell Tumors / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007249:Inflammation / Q000276:immunology; D016173:Macrophage Colony-Stimulating Factor / Q000378:metabolism; D008297:Male; D051379:Mice; D008875:Middle Aged; D011817:Rabbits; D013586:Synovitis, Pigmented Villonodular / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology*; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D014178:Translocation, Genetic / Q000235:genetics
chemical_list: D015703:Antigens, CD; D016173:Macrophage Colony-Stimulating Factor
keywords: PVNS; PVNS-like; Periprosthetic interface membranes; TSGCT; Tenosynovial giant cell tumour; Wear particles