e23571 Background: Soft tissue sarcomas (STS) are a rare, heterogenous group of cancers that tend to have a poor prognosis and few effective treatment strategies. Beta blockers (BB), in particular non-selective BB such as propranolol, have been shown to have an antitumor effect in different malignancies, including breast, colon, and angiosarcomas. The underlying mechanism is unclear but it is thought to be related to the inhibition of beta receptors on malignant cells, which leads to decrease in tumor vascularity and hematogenous spread. In this retrospective analysis, we examined the effect of BB on the outcomes of STS at a tertiary referral center. Methods: Adult patients from 2000 through 2019 with a diagnosis of STS with adequate follow up were included, and were divided into 2 groups: patients on BB at any point during treatment and/or up to 6 months prior to diagnosis, and patients without BB. The patient and tumor data were extracted and analyzed. The primary outcome was overall survival (OS). Statistical methods included descriptive analysis, univariable and multivariable Cox proportional hazard regression analyses and Kaplan-Meier survival plots. Results: 448 patient charts were analyzed. Median age at diagnosis was 55 (range 18-89). 54% were male. 4.9% of patients were diagnosed with stage 4 disease. Histologies included: undifferentiated pleomorphic sarcoma 26.1%, leiomyosarcoma 10%, synovial sarcoma 9.2%, liposarcoma 7.8%, osteosarcoma 2.7%, Ewing sarcoma 2% and others 42.2%. 18.1% of patients were on BB during treatment, with metoprolol the most commonly used (59%). 96% of patients on BB had HTN and 44% had coronary artery disease. Patients on BB were less likely to receive adjuvant therapy (18% vs 26%). Patients on BB were more likely to have stage 4 disease at presentation (9.9% vs 3.8%). Multivariate analysis showed there was no significant difference in overall survival between patients on BB and those not on BB, HR 1.3 (CI 0.8-2.1, p = 0.24). Conclusions: There is no difference in overall survival in patients on beta blockers during treatment for STS after controlling for stage, comorbidities, smoking, and age. Further studies are needed to evaluate the effect of specific beta blocker drugs on soft tissue sarcoma outcomes.
Treatment Strategies for Metastatic Soft Tissue Sarcomas
