LONDON, July 27, 2011 /PRNewswire/ --
New Guidance Could End Postcode Lottery on Innovative Cancer Treatment
The National Institute for Health and Clinical Excellence (NICE) has announced that it has produced guidance to support the routine use of SIRT (Selective Internal Radiation Therapy) for the treatment of patients with liver tumours resulting from colorectal cancer. This welcome decision culminates an extensive dialogue between patients, patient groups, clinical experts and parliamentarians.
SIRT is used for the treatment of inoperable liver tumours and involves injecting millions of tiny radioactive microspheres into the liver via the hepatic artery. Each microsphere is coated with a radioactive isotope which emits beta radiation. The radiation delivers a localised treatment to tumour cells whilst conserving normal liver cells. SIR-Spheres® microspheres, a form of SIRT, were approved in Europe in 2002 and at least 18,000 patients have been treated worldwide. 300 patients have received the treatment in Britain. The NICE guidance, released on 27th July 2011, found there is evidence that SIRT controls liver tumours from colorectal cancer meaning that eligible National Health Service (NHS) patients are now likely to have improved access to this treatment.
Disproportionate access to SIRT has been of great concern to many cancer patients as the treatment can potentially extend life by years. SIRT was originally assessed in 2004 and during the more recent reassessment there has been confusion amongst primary care trusts (PCTs) as to whether they should fund the treatment for eligible patients on the NHS. The reassessment of SIRT has taken NICE two years to complete.
In May 2010 the plight of Dr Becky Smith, a 30 year old NHS surgeon who was refused SIRT treatment by the Isle of Wight PCT because of funding issues, was highlighted by the national media. After receiving national support and offers of funding from individuals Dr Smith was told that the Isle of Wight PCT had made a dramatic U-turn and decided to fund her treatment. Dr Smith has been campaigning for the government to change the system to make this life saving treatment available to all who need it.
Speaking today, Dr Smith said:
"I have without doubt benefitted from treatment with SIRT which has given me precious time to live life to the full. It is great that NICE has supported the use of SIRT, however this decision should have been made much sooner. I hope that this means all eligible patients will get the treatment that they deserve on the NHS."
Dr Harpreet Wasan, Consultant Oncologist at Hammersmith Hospital, Imperial College said:
"SIRT is a pioneering treatment which provides an innovative therapy for patients with inoperable liver tumours that complements chemotherapy. It is excellent news that NICE has now clarified its guidance with the latest evidence and this should ensure appropriately eligible patients can access SIRT on the NHS. I hope that as a result, postcode prescribing and lengthy delays in approving eligible patients for the treatment will be eradicated."
NOTE TO EDITOR:
For full details of the NICE Guidance:http://guidance.nice.org.uk/IPG401
For more details on Sirtex Medical Limited: http://www.sirtex.com
BACKGROUND INFORMATION
Selective Internal Radiation Therapy (SIRT) or Radioembolisation
What is Selective Internal Radiation Therapy (SIRT) or radioembolisation?
Selective Internal Radiation Therapy or SIRT, also known as Radioembolisation, is an innovative therapy that has been developed for the treatment of unresectable primary and secondary liver cancer. The technique involves infusing between 40-80 million radioactive beads (Yttrium-90 resin microspheres) into the arterial blood supply of the liver.
What are SIR-Spheres microspheres?
SIR-Spheres microspheres are radioactive microspheres used in SIRT. SIR-Spheres microspheres deliver targeted internal radiation therapy directly to the tumour(s) with a dose of internal radiation up to 40 times higher than conventional radiotherapy, while sparing healthy tissue.
Direct delivery of SIR-Spheres microspheres via the hepatic arteries helps to achieve maximum disease control through optimal tumour coverage. Randomised controlled trials in patients with liver metastases from colorectal cancer have demonstrated that SIR-Spheres significantly increases the tumour response or disease control rates, as well as significantly extending the time to progression and overall survival.
How do SIR-Spheres microspheres work?
The SIRT procedure enables radiation to be targeted directly into the liver tumours by using the tumour's own blood supply. Healthy liver tissue derives up to 90% of its blood supply from the portal vein (the vein that delivers nutrients to the liver from the gut), with only a small amount of the blood supply being derived from the hepatic artery. In contrast, liver tumours derive up to 90% of their blood supply from the hepatic artery, since they need a profuse supply of highly oxygenated blood. The hepatic artery therefore provides an ideal channel to deliver targeted treatment to the tumour.
SIR-Spheres microspheres are approximately between 20 and 60μm (microns) in diameter which means that following infusion, they are small enough to become lodged in the arterioles within the growing rim of the tumour(s) where they emit a high dose of radiation, but are too large to pass through the capillaries and into the venous system. As SIR-Spheres microspheres are targeted directly at the liver tumours via the hepatic artery, exposure to the remaining healthy liver tissue is minimised. SIR-Spheres microspheres contain the radioactive element Yttrium-90, which delivers beta radiation over a relatively short distance: an average of 2.5mm in human tissue and a maximum of 11 mm. Yttrium-90 has a half-life of approximately two-and-a-half days (64.1 hours), therefore most of the radiation (over 94) is delivered to the tumour in the first two weeks following treatment.
How are SIR-Spheres microspheres different from conventional radiotherapy?
Radiation is an effective agent for destroying tumours and is widely used in cancer treatment. However, the use of external beam radiation to treat liver tumours is limited by the low radiation doses that can be applied to the liver without the risk of radiation damage to the normal liver tissue.
Unlike conventional external beam radiation, SIR-Spheres microspheres selectively irradiate liver tumours and therefore have the ability to deliver more potent doses of radiation directly to the cancer cells over a longer period of time. The therapeutic ratio with SIRT, compared to external beam radiotherapy, is significantly improved and the tumour-absorbed doses from SIRT are typically 4 to 6 times higher than those to the healthy liver tissue.
How is SIRT administered?
Under local anaesthetic, the specially trained interventional radiologist makes a small incision, usually into the femoral artery near the groin. A catheter is then guided through the artery into the liver. The SIR-Spheres microspheres are administered through this catheter. The whole procedure may take around 60-90 minutes. After the procedure is completed, patients may be sent to have a scan to check the level of radioactivity of the SIR-Spheres microspheres in the liver. Patients will be monitored for a few hours after the procedure and most patients are discharged within 24 hours.
What is the regulatory status of SIR-Spheres microspheres?
SIR-Spheres microspheres are approved for use in Australia, the European Union (CE Mark), New Zealand, Switzerland, Turkey and several other countries for the treatment of unresectable liver tumours.
SIR-Spheres microspheres are also fully FDA-approved and are indicated in the U.S. for the treatment of non-resectable metastatic liver tumours from primary colorectal cancer in combination with intra-hepatic artery chemotherapy using floxuridine.
SIR-Spheres® is a Registered Trademark of Sirtex SIR-Spheres Pty Ltd
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