"Tenosynovial giant cell tumour is the unifying term used in the 2020 WHO Soft Tissue and Bone Tumours Classification (5th ed.), with giant cell tumour of tendon sheath also being acceptable 1. They have previously been known as pigmented villonodular tumour of the tendon sheath (PVNTS), extra-articular pigmented villonodular tumour of the tendon sheath, or localised/focal nodular synovitis 11,12. Pigmented villonodular synovitis (PVNS) is no longer a recommended term per the 2020 WHO classification 1."
"Tenosynovial giant cell tumour is the unifying term used in the 2020 WHO Soft Tissue and Bone Tumours Classification (5th ed.), with giant cell tumour of tendon sheath also being acceptable 1. They have previously been known as pigmented villonodular tumour of the tendon sheath (PVNTS), extra-articular pigmented villonodular tumour of the tendon sheath, or localised/focal nodular synovitis 11,12. Pigmented villonodular synovitis (PVNS) is no longer a recommended term per the 2020 WHO classification 1."
"Tenosynovial giant cell tumour is the unifying term used in the 2020 WHO Soft Tissue and Bone Tumours Classification (5th ed.), with giant cell tumour of tendon sheath also being acceptable 1. They have previously been known as pigmented villonodular tumour of the tendon sheath (PVNTS), extra-articular pigmented villonodular tumour of the tendon sheath, or localised/focal nodular synovitis 11,12. Pigmented villonodular synovitis (PVNS) is no longer a recommended term per the 2020 WHO classification 1."
"Tenosynovial giant cell tumour is the unifying term used in the 2020 WHO Soft Tissue and Bone Tumours Classification (5th ed.), with giant cell tumour of tendon sheath also being acceptable 1. They have previously been known as pigmented villonodular tumour of the tendon sheath (PVNTS), extra-articular pigmented villonodular tumour of the tendon sheath, or localised/focal nodular synovitis 11,12. Pigmented villonodular synovitis (PVNS) is no longer a recommended term per the 2020 WHO classification 1."
"The aetiology of tenosynovial giant cell tumours is unknown 1. The WHO classification classes this tumour into subtypes by growth pattern (localised-type vs diffuse-type) and location (intra-articular vs extra-articular) 1. Localised-type tenosynovial giant cell tumours are more common, with a predominance for the hand and wrist, whereas diffuse-type is less common and affects the large joints (e.g. knee, hip, ankle) more 3."
"Tenosynovial giant cell tumour is the unifying term used in the 2020 WHO Soft Tissue and Bone Tumours Classification (5th ed.), with giant cell tumour of tendon sheath also being acceptable 1. They have previously been known as pigmented villonodular tumour of the tendon sheath (PVNTS), extra-articular pigmented villonodular tumour of the tendon sheath, or localised/focal nodular synovitis 11,12. Pigmented villonodular synovitis (PVNS) is no longer a recommended term per the 2020 WHO classification 1."
"desirable: CSF1 rearrangement in selected cases"
"CSF1 translocation 1"
"Tenosynovial giant cell tumours (GCT) are a group of so-called fibrohistiocytic tumours that are usually benign, most often arise from the synovium of joints, bursae or tendon sheaths, and show synovial differentiation 1-5. Despite identical histology, two different subtypes have different clinical presentations and management, and are discussed separately 3,6:"
"essential: intra- or extra-articular location; varying proportions of small histiocytic cells, large amphiphilic cells, foam cells, multinucleated giant cells"
"Surgery is the mainstay of treatment. Recurrence rates are higher in diffuse-type (~35%) compared to localised-type (~18%) 1. Molecular therapy using CSF1 inhibitors such as pexidartinib and vimseltinib is available for treatment of symptomatic tenosynovial giant cell tumours associated with severe morbidity or functional limitations not amenable to improvement with surgery 12; however, pexidartinib carries the risk for serious and potentially fatal hepatotoxicity and is available only through a Risk Evaluation and Mitigation Strategy (REMS) program requiring close liver function monitoring 12."
"On microscopy, the appearance is variable due to differing proportions of mononuclear cells, multinucleated giant cells, foamy macrophages, inflammatory cells, haemosiderin deposition, and stromal collagenisation in different tumours 1. In localised-type tenosynovial giant cell tumours, osteoclast-like giant cells and xanthoma cells are usually frequent, whereas in diffuse-type tenosynovial giant cell tumours, osteoclast-like giant cells are less frequent and often absent 1."