The Chinese University of Hong Kong said on Thursday it is the first in the world to make use of robotic arms to help doctors remove a tumour in the bladder in one piece rather than fragmenting it.

The success came after researchers from CUHK’s faculty of medicine unveiled a new surgical technique, called en bloc resection of bladder tumour (ERBT), which they said can lower the chance of a bladder cancer recurrence compared to old methods.

The medical team said they had since worked with the engineering department to build a robotic system tailored for this surgery, which could help surgeons carry out the procedure with much greater precision.

Professor Kwok Ka-wai, chief engineer of the robotic system, said doctors would have more room to manoeuvre with robotic assistance and reduce the chances of cutting into a tumour during surgery.

“With our robot, we provide extra autonomy," Kwok said.

"Each arm will have five degrees of freedom, a total of 10 degrees of freedom on the left and right, so that you can apply your new strategy of dissecting the tumour in a single piece,” he said.

Peter Chiu is one of three doctors who performed the robot-assisted ERBT operations in a clinical trial that started in December.

He said doctors typically need to observe and assist surgeons in 30 to 50 manual ERBT operations before being able to perform them independently and that the robotic system can help reduce training times significantly.

“For urologists or endoscopists who have experience in using conventional instruments, [experience in] three to five cases should be good," Chiu said.

"And so far, we have done a total of eight cases in this trial.

"And in this trial, we plan to finish 10 cases and then we'll review and move on to the next stage.”

Six of the patients in the trial have been discharged, Chiu said, with no significant complications found a month after surgery.

The research team also said the robotic arms can be used in the future in surgeries involving treatment of gastrointestinal cancers, uterine conditions and biliary diseases.