Scientists have succeeded in creating 3D printed models of tumors by employing the cells of brain cancer patients, allowing for efficacy tests of potential treatments to be run outside of the patient's body before they are implemented for real.

The scientists extract "a chunk" of the tumor from the brain of a patient with glioblastoma – an aggressive cancer with a very poor prognosis – and use it to print a model matching their MRI scans, said professor Ronit Satchi-Fainaro, who led the research at Tel Aviv University.

The patient's blood is then pumped through the printed tumor, made with a compound that mimics the brain, followed by a drug or therapeutic treatment.

While previous research has used such "bioprinting" to simulate cancer environments, the Tel Aviv University researchers say they are the first to print a "viable" tumour.

"We have about two weeks (to) test all the different therapies that we would like to evaluate (on) that specific tumor, and get back with an answer – which treatment is predicted to be the best fit," Satchi-Fainaro said.

A treatment is deemed promising if the printed tumor shrinks or if it lowers metabolic activity against control groups.

The research was published on Wednesday in the journal Science Advances.

Glioblastoma is the most common form of brain cancer in adults. It spreads quickly to other parts of the brain, making it difficult to treat.

Survival is around 40% in the first year after diagnosis and 17% in the second, according to the American Association of Neurological Surgeons.

Researchers have often 3D printed tumor models to plan for surgery, but more recent innovations have focused on bioprinting, which uses live cells as a sort of ink to build up the layers.

Ofra Benny, who leads similar research at the Hebrew University of Jerusalem, said the use of a patient's own cells to develop 3D tumor models could be "a game-changer in the field of personalized medicine."

"The more physiological mimicry you create, the better prediction you get in terms of how drug treatments will work on the actual tumor in the patient's body," she said.