SIO Announces ACCLAIM Clinical Trial with Groundbreaking Support from Industry Partners




18 November 2021


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Nikki Bartoloni

Manager, Marketing & Communications


SIO Announces ACCLAIM Clinical Trial with
Groundbreaking Support from Industry Partners

Washington DC (18 November 2021) – The Society of Interventional Oncology (SIO) announces the launch of the society’s first clinical trial, “Ablation with Confirmation of Colorectal Liver Metastases (ACCLAIM) prospective Trial for Microwave Ablation as a Local Cure.” This multi-million-dollar trial is funded collectively through grants from Boston Scientific Corporation, NeuWave Medical, Inc., (part of Ethicon, Inc.), and Varian, a Siemens Healthineers Company.


In this prospective, multi-center, international trial SIO proposes to establish microwave ablation (MWA) as the preferred treatment option for selected colorectal liver metastases that can be ablated with sufficient margins. The study will be the first global, prospective trial to use an objective and reproducible technical outcome in its study design, which SIO believes will drive important changes to future treatment guidelines. The study will incorporate software to assess the ablation zone and margins and determine if achieving complete margins during an ablation equates to procedural success, where the primary outcome is local disease progression at two-years post-ablation.


Dr. Constantinos T. Sofocleous, MD, PhD, FSIR, FCIRSE, Memorial Sloan Kettering Cancer Center, is the Principal Investigator for the study.  “The ACCLAIM trial could impact patient guidelines with regards to the role of ablation as a treatment option for CRC liver metastases. The study is expected to raise the bar for the standard of care, establishing a reproducible method of achieving tumor ablation with local control,” said Sofocleous. “Clinical research is essential for the continued progress of interventional oncology and SIO will continue to drive such important and focused research efforts.”


Despite a favorable safety profile, historically, the inconsistent local tumor progression (LTP) rates after thermal ablation when compared to surgery have limited the widespread adoption of this treatment option in patients with metastatic colorectal cancer to the liver. Suboptimal outcomes and LTP have been attributed to insufficient coverage of the tumor by the ablation zone (tumor and margins). The ACCLAIM study will estimate disease-free survival of colorectal liver metastases treated with MWA incorporating 3D ablation margin confirmation intraoperatively and through a subsequent independent review centralized validation process.


Dr. Matthew Callstrom, MD, PhD, Professor and Department Chair of Radiology at Mayo Clinic, is President of the Society of Interventional Oncology.  “It’s important to drive what we do as a field forward together, and it takes collaboration and long-term relationships with our industry partners to enable the right studies to be successful,” said Callstrom. “The ACCLAIM Industry Partners are raising the bar for research investment by making an important commitment to support societies like SIO. Together, we are advancing our vision to establish interventional oncology as the fourth pillar of cancer therapy.”


Participants of the ACCLAIM trial will be patients with a diagnosis of colorectal cancer liver metastases. MWA will be performed using an FDA-cleared, commercially available MWA system and using margin confirmation (visualization) software. The ACCLAIM study is set to launch in 2022 with an expected 3-year enrollment period of 275 participants across sites in the United States and Europe.




About the Society of Interventional Oncology (SIO) 

SIO serves as the only membership-based organization dedicated to the emerging field of interventional oncology (IO), working to establish, nurture, and support IO as the fourth pillar of cancer therapy alongside medical, surgical, and radiation oncology worldwide. IO therapies, such as embolization and tumor ablation, combine the expertise of oncology and radiology and use imaging technology to diagnose and treat localized cancers in ways that are precisely targeted and minimally or non-invasive. For more information, please visit


About Boston Scientific, ACCLAIM Founding Trial Partner

Boston Scientific transforms lives through innovative medical solutions that improve the health of patients around the world. As a global medical technology leader for more than 40 years, we advance science for life by providing a broad range of high-performance solutions that address unmet patient needs and reduce the cost of healthcare. For more information, visit


About Ethicon, Inc., ACCLAIM Premiere Platinum Trial Partner

Ethicon, Inc., part of Johnson & Johnson Medical Device Companies, has made significant contributions to surgery for more than 100 years from creating the first sutures to revolutionizing surgery with minimally invasive procedures. Our support of this study aligns with our commitment to help address the world’s most pressing health care issues and improve and save more lives. Through Ethicon’s surgical technologies and solutions, including sutures, staplers, energy devices, trocars and hemostats, and our commitment to treat serious medical conditions like obesity worldwide, we deliver innovation to make a life-changing impact. For more information, visit


About Varian, ACCLAIM Premiere Platinum Trial Partner

At Varian, a Siemens Healthineers company, we envision a world without fear of cancer. For more than 70 years, we have developed, built and delivered innovative cancer care technologies and solutions for our clinical partners around the globe to help them treat millions of patients each year. With an Intelligent Cancer Care approach, we are harnessing advanced technologies like artificial intelligence, machine learning and data analytics to enhance cancer treatment and expand access to care. Our 11,000 employees across 70 locations keep the patient and our clinical partners at the center of our thinking as we power new victories in cancer care. Because, for cancer patients everywhere, their fight is our fight. For more information, visit and follow @VarianMedSys on Twitter.

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