Therapy adherence after interdisciplinary tumour board discussion is associated with improved outcome in soft tissue...

Centralising soft tissue sarcoma (STS) treatment in expert centres and implementing comprehensive therapy concepts through interdisciplinary tumour boards (ITB) has led to significant treatment progress. However, our knowledge on the implementation of the ITB recommendations and its impact on patient outcome is limited. In this retrospective analysis, we examined a cohort of 222 adult patients (pts) with primary STS who were presented to the ITB of the Charité Comprehensive Cancer Centre between 2015 and 2020. In localised disease (n = 188), resection was recommended in 71% (n = 134) of pts. The treatment modalities chemotherapy with or without regional deep hyperthermia, and radiotherapy were recommended in 37% (n = 69), 26% (n = 48) and 52% (n = 97), respectively. Complex multidisciplinary concepts were established in 29% (n = 54) including ≥3 treatment modalities. Only partial adherence, either by choice of patient or treating physician, was associated with a higher risk of both progression (HR 4.0 95%-CI 1.6-9.7 p < .01) and mortality (HR 5.3 95%-CI 1.7-16.4 p < .01). Pts inable to follow the ITB recommendations due to complications or rapid progression showed a high-risk profile with increased mortality and progression rates (HR 18.1 95%-CI 8.5-38.2 p < .001; HR 21.5 95%-CI 8.5-54.7 p < .001). To our knowledge, this represents the first German Comprehensive Cancer Centre analysis of therapy adherence in STS. It provides further real-world evidence that full adherence to ITB recommendations and the ability to adhere to them are of prognostic value for patient outcome and underlines the importance of interdisciplinary decision-making and treatment planning for STS patients.