World’s largest venous access trial commences in the UK

Jon Moss
Jon Moss

Interventional News has learned that the UK CAVA trial, a four-way randomised controlled trial of long-term venous access devices for the delivery of chemotherapy (Ports versus tunnelled central lines versus peripherally inserted central catheters) has begun. 

The CAVA (Cancer and venous access) trial seeks to determine which device—subcutaneously tunnelled central catheters (Hickmans), peripherally inserted central catheters (PICCs) or implantable chest wall ports (Ports)—offers the best outcome from safety, clinical effectiveness and cost-effectiveness perspectives. The trial will randomise 2000 patients over three years and will be the world’s largest venous access trial.


There is currently no evidence-based guidance to help choose between these devices and the decision-making processes behind choice of device, which varies from centre to centre, is poorly understood.

The four-way randomisation is divided into PICC vs. Port (superiority design) in one arm, PICC vs. Hickman (inferiority design) in the second arm, Port vs. Hickman (superiority design) in the third arm and Port vs. PICC vs. Hickman. “This covers all eventualities; i.e. if a patient is not suitable for one device, (for instance, haematologists generally do not like Ports) then they can still be randomised into one of the other arms,” said Moss.

The investigating team in Glasgow, led by Jon G Moss, Interventional Radiology Unit, NHS Greater Glasgow and Clyde, Gartnavel General Hospital, Scotland, say venous access is seen by many interventionalists as a low key topic increasingly delegated to nurse practitioners and falling well below, for example, aortic stent grafting in the “wow” factor. However the National Institute of health Research (NIHR) took a different view and in 2011 put out a commissioned call for research to compare PICCs, Hickmans and Ports in patients receiving chemotherapy of more than 12 weeks duration.


“Interventional radiologists must engage with venous access. Although its bread and butter stuff it is a very high activity sport, important to patients and healthcare systems worldwide. EVAR and TEVAR might make the headlines for doctors and a small number of patients, venous access impacts on millions of patients. In this high tech world, it is the EVARs and TEVARs that take the limelight, but interventional radiologists must not ignore venous access— it is a duty to millions of patients,” Moss told Interventional News.

The National Chemotherapy Advisory Group estimated approximately 65,000 chemotherapy programmes per year and Hospital Activity Data for England reported 425,000 deliveries of chemotherapy for cancer in the year 2009–2010.

The trial has randomised 32 patients from Glasgow, Manchester, Leeds and Newcastle to date. “Birmingham and Durham will open recruitment shortly and St George’s will join as the London site,” Moss added. He explained that the centres have all been chosen because of the significant number of venous access devices they use plus their strong commitment to a research ethic and deliverability. 

“The dominant strategy at present is a Hickman, followed by PICC with Ports being used infrequently. There is a gradual shift away from Hickman towards PICC in some centres which may be due to evolving nurse-led delivery. Ports offer many potential advantages which include fewer complications, less maintenance, reduced treatment interruption, improved quality of life and patient satisfaction. However Ports are the most expensive device and their cost-effectiveness is unknown. It is likely that the initial cost and the slightly more complex insertion procedure is limiting usage. The decision-making processes behind choice of device is poorly understood and varies from centre to centre. In addition to clinical factors, the views of the oncologist, nurse or radiologist, the availability of staff, cost pressures and who places the device all play an unknown role. Currently there is no evidence-based guidance to help choose between them. Venous access services are evolving and there is an increasing input from dedicated nurse specialists. In some of the more proactive centres, these nurses will discuss the options with a patient and then place the device. This nurse-driven service is usually under the supervision of either anaesthetists or interventional radiologists. Surgeons rarely have any significant input in UK practice,” the investigators write.