Global cancer study to explore link between gas anaesthesia and likelihood of relapse
Melbourne scientists will spearhead a global study to see whether the use of gas anaesthetics on cancer patients who undergo surgery could contribute to a higher risk of the cancer recurring.
- A previous study on mice linked gas anaesthesia with an increased risk of cancer relapse
- Patients should not be concerned that anaesthetics are unsafe, the lead researcher said
- Some hospitals are already choosing to use intravenous anaesthetic in favour of gas anaesthetic for cancer surgeries
The study, which will run for five years and include 5,700 patients, is likely to shape the way cancer surgeries are managed worldwide, according to Peter MacCallum Cancer Centre’s Bernhard Riedel, who is a chief investigator on the project.
Professor Riedel said there was “mounting evidence” that gas-based anaesthetics — also known as “volatile anaesthetics” — could promote the growth of any cancer cells left in the body after surgery.
He said a study on mice had found that those who were given intravenous anaesthesia had higher rates of cancer survival than those who were treated with anaesthetic gases, suggesting gas anaesthetics could increase the risk of a cancer relapse.
“There’s some literature that’s suggesting … that some of the volatile gases may drive some of the cancer pathways, and so if there’s any residual disease or cancer that’s left undiagnosed at the time of surgery, this has a chance to get a foothold and lead to recurrence,” he said.
“These gases don’t cause cancer … these gases [may] add fuel to the fire.”
Professor Riedel said some hospitals were already favouring the use of intravenous anaesthesia over gas-based anaesthesia in light of those studies, but there was still no “robust” evidence available to warrant a ban on the use of volatile anaesthesia.
Gas-based anaesthetic has been the most commonly used form in surgeries for decades. (ABC News: Jessica Longbottom)
Gas anaesthetic still ‘safe’
He said despite the need for the study to improve anaesthetists’ best practice, patients should not be concerned that gas-based anaesthetics are unsafe.
“The workhorse of anaesthesia has always been volatile-based anaesthesia, it’s used by the majority of anaesthetists, it’s safe … the opportunity to study this and see whether we can make it a little bit safer for the cancer patient is important,” Professor Riedel said.
“The volatiles are easy to turn on, they’re titratable … they’re easy to switch off, they’ve been the primary technique used by anaesthetists for decades.”
The study’s synopsis said 80 per cent of anaesthetists routinely used inhaled anaesthesia and 50 per cent of respondents felt that the anaesthetic technique used impacted cancer outcomes.
“This lack of clinical consensus on optimal anaesthesia reflects the need for a definitive randomised clinical trial,” the synopsis stated.
The trial — which will involve international collaboration between scientific centres — will examine whether the already widely used intravenous anaesthetic propofol could reduce inflammation and cancer relapse in patients being treated for lung and colorectal cancers.
The Federal Government has committed $4.88 million towards the research, which is being jointly coordinated by the Peter MacCallum Cancer Centre and the University of Melbourne.