Propofol-based anaesthesia does not improve cancer-related outcomes.Propofol-based anaesthesia does not improve cancer-related outcomes in patients undergoing surgical resection of malignancies in the GA-CARES* trial.
In 2015, experts called for prospective investigations on whether the anaesthetic technique used during oncologic resections affects cancer-related outcomes. [Br J Anaesth 2015;114:2-3]
“In response to this call, we [conducted the GA-CARES trial] to test the hypothesis that the use of propofol (vs volatile anaesthesia) improves overall survival (OS) and disease-free survival (DFS) in patients with biologically aggressive cancers,” the researchers explained. “[W]e found no evidence that propofol-based anaesthesia improves cancer-related outcomes compared with volatile anaesthesia.”
In the intention-to-treat (ITT) population, propofol recipients did not show improved survival (26.1 percent vs 22.9 percent deaths; hazard ratio [HR], 1.16; p=0.115 by exact stratified log-rank test). [Anesthesiology 2026;144:51-62]
In the per-protocol (PP) cohort, more patients in the propofol group died through the 2-year follow-up (25.5 percent vs 20 percent; HR, 1.31; p=0.017). A similar pattern was observed for DFS (HR, 1.10; p=0.428) and was consistent across various subgroups.
“These two separate analyses can be useful for different reasons. The ITT analysis, which is the accepted standard for many large randomized controlled trials, minimizes several sources of potential bias that might be introduced by investigators/clinicians. However, it can include patients with factors (eg, no confirmed cancer at surgery) that could dilute the effect size,” the researchers explained.
Conversely, the PP analysis is an attempt to give the intervention the best chance of showing a benefit—if it does exist, they continued. “For this reason, it made sense for us to exclude [certain] patients from this analysis.” These patients were those who had benign pathology, aborted surgery, or those who did not receive the assigned anaesthetic.
Moreover, although volatile anaesthesia had an edge over the propofol-based approach in the PP analysis, the result was statistically fragile, they highlighted. “[T]herefore, our interpretation is that propofol anaesthesia does not confer a beneficial effect [in the PP analysis].”
“In conclusion, our trial does not support the hypothesis that propofol-based anaesthesia improves cancer-related outcomes in patients undergoing resection of biologically aggressive malignancies,” the researchers concluded.
The study included 1,766 adult patients (mean age 65.6 years, 58.4 percent men) from five US centres undergoing surgical resection of cancers associated with poor outcomes (bile ducts, bladder, liver, lung, oesophagus, pancreas, peritoneal surface, or stomach).
The participants were randomized 1:1 to propofol or a volatile halogenated ether (ie, desflurane, isoflurane, or sevoflurane) for the maintenance of general anaesthesia. Most patients in the volatile group received sevoflurane (65.8 percent). The PP cohort comprised 1,411 participants.
A majority of the participants (n=1,316) received surgery as part of their first treatment course, 219 did so for recurrent or progressive disease (bladder, liver, lung, or peritoneal sites), and 140 had aborted or cancelled surgery (usually for unresectable disease).
In-hospital mortality rates were similar between groups (n=11 each), as was median postoperative hospital length of stay (5 days for both; p=0.755).
In the ITT population, the overall mortality rate through 2 years after randomization was highest in aborted cases (58.6 percent), followed by surgery for recurrent disease (22.8 percent). The mortality rate through 2 years was highest for biliary cancer surgery (radical cholecystectomy or bile duct resection; 50 percent). For the other planned surgeries**, the mortality rates were as follows: 44 percent (peritoneal), 38.7 percent (pancreas), 34.3 percent (oesophagus), 29.2 percent (bladder), 27.8 percent (stomach), 22.7 percent (liver), and 13.6 percent (lung).