Celebrating Sarcoma Awareness Month with the start of EU-funded STREXIT 2 project study

On Sarcoma Awareness Month, the European Organisation for Research and Treatment of Cancer (EORTC) and the Syreon Research Institute are delighted to announce the official start of STREXIT 2, an observational arm of the EORTC 1809 STRASS 2 clinical trial focusing on high-risk retroperitoneal sarcoma. 

STREXIT 2 is one of three research projects coordinated by the EORTC, alongside DE-ESCALATE and LEGATO, which have recently received funding from the EU Horizon programme. The study will span over a duration of five years. 

Sarcomas are a rare and aggressive form of cancer that affects the body's soft tissues. Specifically, retroperitoneal sarcomas impact the abdomen and constitute 15% of all soft-tissue sarcomas. Retroperitoneal sarcoma is an extremely rare and aggressive tumour occurring in 0.5 to 1.0 per 100,000 individuals in the population. Its diagnosis is challenging, and treatment proves difficult. Certain subtypes, such as high-grade dedifferentiated liposarcoma and leiomyosarcoma, present particularly high risks, with a 70% mortality rate five years after treatment. There is a clear need for new and better treatments for retroperitoneal sarcoma, which is generally treated with just surgery alone. 

STRASS 2 is a multicentre, open-label phase III international clinical trial that investigates treatment options (neoadjuvant chemotherapy followed by surgery versus surgery alone) for patients with high-risk retroperitoneal sarcoma (RPS). This is the first official trial looking into the potential benefits of chemotherapy before surgery to improve disease control and survival in patients burdened by this rare cancer.  

 In June 2023, work on the set-up of a new observational arm called STREXIT 2 officially started. This arm will be added to the ongoing STRASS 2 clinical trial to gather real-world data from patients who do not meet the eligibility criteria for STRASS 2. The objective is to compare the clinical outcomes between STRASS 2 and STREXIT 2 and to explore the possible combination of STRASS 2 and matched STREXIT 2 patients. This will strengthen the results obtained from the randomised clinical trial data and increase the power of subgroup analyses. 

The early incorporation of real-world data (STREXIT 2) into the trial (STRASS 2) will enrich the study population and provide a pragmatic approach to addressing crucial causal questions within a rare cancer population. 

A positive outcome of the trial will help to understand the clinical added value and cost-effectiveness of neoadjuvant chemotherapy before surgery for high-risk retroperitoneal sarcoma. To determine the latter, a health economics analysis will be performed assessing the economic value of different treatment scenarios based on STRASS 2 and STREXIT 2. 

The STRASS 2/STREXIT 2 study will run in 11 countries in Europe, including Cyprus, the Czech Republic, Denmark, France, Germany, Italy, the Netherlands, Poland, Slovakia, Spain, and the UK. Moreover, intergroup collaborations have been set in place with Canada (Canadian Cancer Trials Group), Australia (Australian and New Zealand Sarcoma), and the United States (ECOG-ACRIN Cancer Research Group). STRASS 2 aims to recruit 250 patients in total. 

The STRASS 2/STREXIT 2 study provides a unique opportunity to study the optimal treatment for retroperitoneal sarcoma patients with the possibility of changing clinical practice. This could lead to improved patient survival and quality of life but also improve health system sustainability. This is a multidisciplinary and multistakeholder consortium involving clinical oncologists, surgeons, health economists and patient representatives. 

Learn more about EORTC 1809 – STRASS 2/ STREXIT 2 here.