High-intensity focused ultrasound (HIFU) can enable the immune system to fight cancer, a report in this month's Journal of Translational Medicine has revealed.
HIFU is already used to kill cancerous cells by heating them, but researchers from Duke University's Pratt School of Engineering - in collaboration with cancer experts from the Duke Comprehensive Cancer Center - have found that the technique is even more effective if it is used in the first instance to make the cells vibrate.
The shaking causes the membrane to rupture, so that the cells spill their contents.
This then triggers an alarm which activates the immune defences, generating tumour-contending white blood cells.
Pei Zhong, an author of the study, said: "Our results show that while mechanical HIFU is not as effective as thermal HIFU in killing tumour cells directly, it has the potential to induce a stronger anti-tumor immune response.
"These preliminary findings open up the possibility that we could use heat from HIFU to treat the primary tumour and HIFU-boosted immunotherapy for combating any residual and metastatic tumour cells."
Cancer cells often remain undetected by the immune system for reasons which are not fully understood.