On 29 August, the UK’s National Institute for Health and Clinical Excelence (NICE) published guidance supporting the use of contrast-enhanced ultrasound with SonoVue (Bracco) to diagnose liver cancer.
The guidance recommends the use of SonoVue in adults to investigate lesions to the liver that is detected incidentally, but not characterised, on an unenhanced ultrasound scan. The guidance also recommends its use in adults to investigate potential liver cancer that has spread from other cancers in the body, and to investigate liver damage in adults with cirrhosis where unenhanced ultrasound (US) scans are inconclusive, and if contrast-enhanced computed tomography (CT) and contrast enhanced-magnetic resonance imaging (MRI) respectively cannot be used.
Sometimes when liver lesions are found with an initial unenhanced US scan, the liver abnormality cannot be characterised and the patient is then usually referred for additional imaging using MRI and/or CT. This may lead to waits of several months with consequent distress to patients and families. In addition, there are potential drawbacks in using these other imaging techniques; CT uses ionising radiation and the intravenous contrast agent can, on rare occasions, cause kidney damage and some patients cannot have an MRI scan due to pacemakers while others find the examination causes claustrophobia.
SonoVue is a second generation contrast agent and is licensed for contrast-enhanced ultrasound imaging in adults in whom unenhanced ultrasound is inconclusive. It uses sulphur hexafluoride microbubbles which are injected into the bloodstream to enhance the blood’s ability to reflect ultrasound waves (echogenicity) and thus improve the signal to noise ratio in ultrasound. It improves display of the blood vessels in liver lesions during ultrasound scanning, allowing more specific characterisation of lesions.
Carole Longson, director, NICE Health Technology Evaluation Centre, said: “Ultrasound scanning, along with other imaging technologies such as CT and MRI, are important in diagnosing and planning treatment for many patients with liver disease. One drawback with unenhanced liver imaging is that it sometimes identifies damage to the liver which cannot be characterised initially and another test may therefore be needed to fully explain the abnormality. One important potential benefit of SonoVue is that it can be carried out at the same appointment as the initial scan, thereby minimising any delay to diagnosis and subsequent treatment, with associated reduction in anxiety for patients and their families.
“The independent Diagnostics Advisory Committee concluded that the evidence presented showed that contrast-enhanced imaging with SonoVue is less costly and more effective compared to contrast-enhanced CT and MRI for characterising incidentally detected liver lesions. The Committee also concluded that SonoVue is an effective use of NHS resources in patients with suspected cancer of the liver that has spread from other cancers in the body and in patients with liver cirrhosis for whom CT scanning or MRI scanning respectively are not suitable.”