Outcome of Surgical Treatment for Patients with Diffuse-Type Tenosynovial Giant Cell Tumours

OBJECTIVE: Diffuse-type Tenosynovial Giant Cell Tumour (TGCT) is a rare, locally aggressive and difficult to treat disease. An international multicentre-pooled retrospective study of individual patient data was developed to describe global treatment protocols, evaluate oncological outcome, complications and functional results. A secondary study aim was to identify risk factors for local recurrence after surgical treatment. METHODS: Patients treated in 31 sarcoma reference centres between 1990 and 2017, with histologically proven diffuse-TGCT of large joints were included. Of 1192 cases of diffuse-TGCT, 58% were female with a median age 35 years. 64% affected the knee and in 54% primary treatment was one-staged open synovectomy. Risk factors were tested in a univariate analysis and significant factors subsequently included for multivariate analysis, with first local recurrence after surgical treatment in a tertiary centre as the primary outcome. RESULTS: At a median follow-up of 54 (95%CI 50-58) months, recurrent disease developed in 44% of all surgically treated cases, with local recurrence free survival (RFS) at 3, 5, 10 years of 62%, 55% and 40%, respectively. The strongest risk factor for recurrent disease was prior recurrence (HR 3.5 95%CI 2.8-4.4, p 35years), bone-involvement (present;absent), surgical technique (open;arthroscopic) nor tumour size (<5cm;≥5cm) yielded an association with the first local recurrence. CONCLUSION: This largest international individual data study of patients with diffuse-TGCT, provides a comprehensive and up to date disease overview, evaluating the clinical profile and management of the disease. Since complete resection of diffuse-TGCT could be regarded as nearly impossible and recurrence rates are unacceptably high after both arthroscopy and open synovectomy in the knee, even in specialized centres, a multimodality approach in this disease, including adjuvant treatments, is warranted. FUNDING STATEMENT: The department of orthopaedics of the Leiden University Medical Centre (LUMC) receives research funding by Daiichi Sankyo. DECLARATION OF INTERESTS: Emanuela Palmerini, Daiichi Sankyo: advisory board and research funding to my Institution for clinical studies in which I am involved. Eris Staals, Daiichi Sankyo: advisory board and research funding to my Institution for clinical studies in which I am involved. Silvia Stacchiotti, Daiichi and Novartis: research funding to my Institution for clinical studies in which I am involved. The authors not stated above do not have a conflict of interest regarding this manuscript. ETHICS APPROVAL STATEMENT: This study is conducted according to the Declaration of Helsinki (October 2013) and approved by the institutional review board (CME) from the Leiden University Medical Center (LUMC) (May 4th, 2016; G16.015).