Impact of interdisciplinary sarcoma board evaluation on treatment outcome of primary soft-tissue sarcoma patients.
Authors: Striefler Jana Kaethe , Strönisch Annika , Rau Daniel , Kaul David , Koulaxouzidis Georgios , Oellinger Robert , Von Laffert Maximilian , Schäfer Frederik Maximilian , Keilholz Ulrich , Bullinger Lars , Märdian Sven , Flörcken Anne 
Published: June 2021

e23540 Background: Early presentation of soft-tissue sarcoma (STS) patients to a specialized sarcoma center including discussion in the interdisciplinary sarcoma board (ISB) prior to surgery is essential to the treatment of sarcomas. This approach significantly improves patient survival and guideline coherence. However, there exists only limited information on the adherence to the recommendations of the ISB. Accordingly, we decided to analyze a STS cohort at a large German sarcoma center focusing on outcome parameters and adherence to quality parameters defined by the German Cancer Society (Deutsche Krebsgesellschaft). Methods: In a retrospective data analysis, we identified n = 230 adult patients presented at the ISB of the Charité–Universitätsmedizin Berlin in Germany from January 2015 until December 2019. Inclusion criteria were as follows: newly diagnosed STS, presentation during first-line therapy and recommendation of at least one treatment modality such as surgery, chemotherapy, radiotherapy, regional hyperthermia or follow-up by the ISB. Clinical and follow up data was collected by using the hospital information system and the outpatient network. Results: Our patient cohort included 53% male and 47% female patients with a median age of 58 years (range 19-96). The majority (86%) showed a localized tumor stage, while 14% already had metastases. In 24% of the cases the sarcomas were classified as low-grade, in 76% as high-grade. Surgery was recommended for 66% of the cases, for 80% of them combined with chemotherapy, radiotherapy or hyperthermia. 14% of the patients received a recommendation for all 4 modalities. For 9% of the patients, chemotherapy alone was recommended. Both overall survival and progression-free survival was significantly higher in the group with complete adherence to the recommendations of the ISB (p < 0.001). The worst prognosis was found in patients unable to adhere to the recommendations due to rapid progression or complications of the therapy (HR for death 15.06, 95%CI 7.94-32.22). If one recommended modality was not carried out, there also was a higher risk of death (HR 4.38, 95%CI 1.75-10.96). Most common reasons were patient refusal or individual decision by the treating physician. A metastasized tumor stage was associated with an increased risk of death (HR 2.62, 95%CI 1.45-4.75). In contrast, neither the histological grading (low vs. high) nor age did influence the mortality significantly. Conclusions: In our cohort of STS patients, survival depends significantly on adherence to the recommendations of the ISB. Our analysis at a German sarcoma center is in line with previous international reports demonstrating the importance of interdisciplinary decisions and therapeutic adherence. We hereby underline the essential role of interdisciplinary approaches in care of STS patients and the effort to implement defined quality parameters.