Cancer trap grabs wandering tumour cells to warn of early spread

The trouble with cancer is it spreads – sometimes even before someone knows they are ill. A small implant that traps cancer cells as they migrate through the blood could make a lifesaving early-detection system.

“This could be the canary in the coal mine,” says Lonnie Shea of the University of Michigan at Ann Arbor, one of the developers.

So far the idea has been tested in mice. If it translates to people, then once it is in place the implant could be scanned for cancer cells while inside the body – either by doctors, or one day perhaps just with a smartphone. “That’s the fantasy,” says Shea.

Shea devised the approach along with Jacqueline Jeruss, a breast cancer surgeon. Jeruss had noticed how common it was for her patients’ first symptom to be breathlessness – as the cancer had already spread to their lungs.

They and their colleagues devised an implant made from an inert porous material already used in medical devices, and loaded it with a signalling molecule called CCL22. This attracts certain immune cells, which encourages cancer cells to follow suit.

They implanted the device under the skin of mice with a version of breast cancer – and found tumour cells in it after two weeks.