News Release

Low dose internal radiotherapy prevents artery narrowing

Peer-Reviewed Publication

ECCO-the European CanCer Organisation

One of the drawbacks of angioplasty, a procedure whereby a balloon catheter is used to widen blocked coronary arteries, is a re-narrowing of the treated artery (restenosis), which means patients have to undergo further treatment. The use of metallic stents* has reduced the frequency of restenosis to around 20%. For those patients who have a recurrence following stent implantation the risk of repeat narrowing is as high as 80% and many will undergo repeated angioplasties, or even heart bypass surgery. An international trial has now shown that intravascular brachytherapy (internal radiotherapy) using beta radiation can prevent this re-narrowing by reducing the re-growth of tissue within the stent.

Dr. Ian Crocker from the Department of Radiation Oncology at Emory University School of Medicine, Atlanta, USA, presented results from the START** trial, conducted in 50 North American and European centres, today (Tuesday 19 September) in Istanbul to delegates at the European Society for Therapeutic Radiology and Oncology conference. "This is the first clinical trial to evaluate the safety and effectiveness of beta, rather than gamma, radiation for patients with in-stent restenosis", he said.

Immediately following the procedure to open their blocked stents, 476 patients were randomised to receive either a beta radiation source (Strontium 90) for 3-5 minutes or placebo (no treatment). Eight months later, all patients returned for an angiogram, an X-ray technique used for diagnosing changes in the arteries.

Dr. Crocker said that patients treated with beta radiation had a significant reduction in major adverse cardiac events, as well as a 34% reduction in the number of repeat procedures. Within the stent itself, a 66% reduction in restenosis was observed.

In recent clinical trials of vascular brachytherapy, there has been some concern about late thrombosis (clot) in patients receiving new stents in conjunction with radiation. Of the 21% of patients in the START study who were implanted with new stents, no cases of clinical stent thrombosis were reported.

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19 September 2000

Notes for editors:

* A stent is a narrow, flexible tube made from metal that acts as a scaffold inside the artery to keep it open.

** START = STents And Radiation Therapy Trial

The European Society for Therapeutic Radiology and Oncology (ESTRO) was founded in 1980 as a society of individual members working in the field of radiotherapy and oncology. It aims to improve the treatment of cancer patients by establishing the integration of radiation oncology with other methods of treatment (e.g. surgery, chemotherapy), and by establishing best practice in radiotherapy. ESTRO has more than 5000 members throughout Europe.



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