“I do not want interventional radiology to be a treatment for the rich, nor for those who live in the wealthiest countries.” Yasuaki Arai is an interventional radiologist who was, until recently, executive advisor to the president at Japan’s National Cancer Center in Tokyo, where he is currently a member of the interventional radiology centre. He founded the Japan Interventional Radiology in Oncology Study Group (JIVROSG) and is a prolific physician-inventor, including of the tip-deflecting microcatheter. He answers some of Interventional News’ questions.
What attracted you to a career in interventional radiology (IR)?
IR attracted me because it was an area where I knew that my enthusiasm, skills, ideas and efforts could improve patient distress directly and quickly. No other medical specialty ever really appealed to me as much, but prior to deciding to become a doctor, I did think I would like to be a chef.
Who are, or were, your mentors?
When I started in IR, the specialty did not exist in Japan yet. So, I did not have a mentor. I learned angiography from a book, but I did the rest while thinking for myself. For me, my patients may have been a kind of mentor, as it was their conditions and also the patients themselves that would tell me whether the procedure I had done was right or wrong, good or not so good for them.
Could you describe a particularly memorable case of yours?
Selecting one case is not easy, but doing novel procedures that no one anywhere in the world has done before is always memorable. For example, the implantation of a catheter and port system via the left subclavian artery for hepatic arterial infusion chemotherapy; extra-anatomical shunt creation between the hepatic vein and the ascites cavity, the portal vein and the splenic vein, between biliary
trees, and so on.
You founded the JIVROSG: what prompted you to set this group up?
I learned the importance of clinical trials and evidence in discussion with medical oncologists when I presented the results of hepatic arterial infusion chemotherapy for liver metastasis at a conference. It was one of the international conferences of loco-regional treatment that took place during the 80s in Europe. The oncologists I met taught me that randomised controlled trials (RCTs) are necessary for proper scientific evaluation of emerging treatments. It made sense to me then that conducting clinical trials and presenting evidence is something that we should be doing in Japan too.
And what are some of the most exciting findings to come out of the JIVROSG?
There are two purposes of JIVROSG clinical trials. One is to answer clinical questions in IR. Another is to be able to use evidence to obtain approval for IR devices that, until that point, did not have sufficient evidence to support approval. In the case of the former, the positive results of an RCT of palliative IR procedures such as percutaneous vertebroplasty for painful bone metastases and percutaneous transoesophageal gastric tubing (PTEG) to relieve patients of the pain associated with standard nasogastric tubes were very exciting. An example of an exciting finding of the latter variety was a clinical trial of conventional transarterial chemoembolization (cTACE) for hepatocellular carcinoma (HCC) in collaboration with scientists in South Korea. With this clinical trial, lipiodol for TACE was approved in Japan, and then approved all over the world. Similarly, a clinical trial of the liquid embolic material N-butyl 2-cyanoacrylate (NBCA) is due to be approved in Japan. We hope it will go on to have an even wider-reaching impact on the world of IR.
What are the most challenging aspects of using IR techniques to diagnose and treat cancers?
Progress in IR happens at a rapid pace and sometimes this is even too fast for the evidence to be recognised by physicians outside of IR. As a result, sometimes IR procedures are not recommended, even when the patient is a good candidate for IR treatment. This is probably one of the most challenging aspects of using IR to diagnose and treat cancers. We will need to put in continual effort to make IR a standard treatment in modern medicine.
You have been involved in research and development to bring a number of medical devices to market such as the implantable port and the tip-deflecting microcatheter. What is an example of a cutting-edge device that is currently transforming how you treat patients in your field?
There are many fascinating, unsolved problems. Of most interest to me is how we treat stenotic lesions of the small intestine. With advances in endoscopy, the gastrointestinal tract and bile ducts are becoming less the domain of the interventional radiologist, and more the field of endoscopists. However, the small intestine, which the endoscope cannot reach, remains the realm of IR. I hope to establish techniques and devices to treat stenotic lesions of the small intestine percutaneously.
As former executive advisor to the president at Japan’s National Cancer Center, what are your hopes for the future of interventional radiology in oncology?
The recent progress of systemic medical treatments with molecular target agents and immunotherapies is tremendous. However, I feel that the importance of regional treatments such as surgery, radiation therapy and IR are sometimes forgotten about. There are not many cancers that can be completely treated with systemic medical therapy alone. So, I think it is very important to work on establishing guidelines for the appropriate combinations of systemic therapy and IR for particular types of patients. I hope that IR will, before too long, be recognised as one of the undisputed standard therapies in oncology.
You were named a distinguished fellow at Cardiovascular and Interventional Society of Europe (CIRSE) 2017. What would you like to see the 2022 meeting’s programme include?
Unfortunately, there is a big gap within the world of IR, not only between IR and other specialties. It is the gap between the economically rich and less rich countries. The progress of IR is great, but the costs involved are also growing rapidly. I do not want IR to be a treatment for the rich, or those who live in the wealthiest countries. I think it is very important to enable patients who live in poorer countries to be treated with IR. It will not be easy, but it would be great if we could start discussing how we go about bringing ‘cheaper IR’ into worldwide medical practice.
This year, the Japanese Society of Interventional Radiology (JSIR), the Asia Pacific Society of Cardiovascular and Interventional Radiology (APSCVIR), and the International Symposium of Interventional Radiology (ISIR) are holding a joint meeting. What are the most common issues facing IR in the widespread geographical region that is Asia and the Pacific?
The area of Asia is very large, and the economic situation, medical systems and social attitudes are very different country to country. So, the biggest problem with IR in Asia is that it is difficult to all come together as professionals working in diverse countries to make unified recommendations or establish common practices. However, more IR doctors than ever before will participate in APSCVIR 2022, which is a step in the right direction. Also, APSCVIR has been playing a central role in promoting educational programmes through webinars, and this has allowed IR professionals to share ideas and practices across geographical, cultural and economic borders.
What are your hobbies and interests outside of medicine?
Mountain climbing, playing music and cooking are some of my favourite pursuits. Mountain climbing and cooking are similar to IR, because I must make decisions quickly in order to achieve the best results; the results will clearly reveal whether my decision was a good one or not. As for music, I perform in a live ‘Beatles Night’ concert with professional musicians every four months. I play bass, piano and do vocals, and I think that music is more difficult than my work as an IR.