Laurent Dercle MD, Presenter: Nothing to Disclose

Samy Ammari, Abstract Co-Author: Nothing to Disclose

Roland Chisin MD, Abstract Co-Author: Nothing to Disclose

Quentin Gillebert, Abstract Co-Author: Nothing to Disclose

Laurence Vilcot, Abstract Co-Author: Nothing to Disclose

Martin Schlumberger, Abstract Co-Author: Nothing to Disclose

Clarisse Dromain MD, Abstract Co-Author: Nothing to Disclose

Frederic Courbon, Abstract Co-Author: Nothing to Disclose

- Diagnosis of the local extent of the disease (surgery): MRI and/or FDG-PET/CT - Malignant transformations - Response to targeted therapies: FDG-PET/CT

Introduction: Tenosynovial giant cells tumors [T-GCT] are benign but locally aggressive tumours with a high recurrence rate. The main challenges are the diagnosis of the local extent of the disease, of malignant transformations and to monitor the response to targeted therapies. Teaching Points: The definitive diagnostic is based on biopsy-obtained histopathology. The main imaging features are the presence of a soft tissue mass or hypertrophy in the synovium or bursa or tendon sheath (MRI, CT-scan or 18F-FDG-PET/CT); hemosiderin deposition (MRI); increased FDG-uptake (PET); extrinsic erosion of bone with well-defined sclerotic margins on CT-scan. MRI is the current reference-standard for the pre-operative with a pattern highly specific of hemosiderin deposition in the macrophages (low T2-signal intensity and blooming artefact with gradient-echo sequences). The differential diagnoses include synovial haemangioma and haemophiliac arthropathy. Targeted therapies are responsible for a late symptomatic improvement. MRI and RECIST fail to predict the response to treatment. As a contrary, FDG-PET/CT and PERCIST are good predictor of the response.

http://abstract.rsna.org/uploads/2014/14018791/14018791_4uvh.pdf

Dercle, L, Ammari, S, Chisin, R, Gillebert, Q, Vilcot, L, Schlumberger, M, Dromain, C, Courbon, F, FDG-PET/CT, CT and MR Imaging of Tenosynovial Giant Cells Tumors.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14018791.html