Scientists have identified a brief window after brain tumour surgery during which a treatment for glioblastoma can cross the brain’s protective barrier and reach the cancer cells most likely to trigger tumour regrowth. 

The discovery could pave the way for more effective treatments for glioblastoma, the most common and aggressive form of brain cancer in adults. 

Researchers from The University of Manchester found that surgery itself creates two short-lived periods when the protective membrane, known as the blood-brain barrier, becomes temporarily more permeable around the edge of the surgical cavity. 

By administering cancer treatments packaged inside nanomedicines during these windows, the team showed they could selectively deliver chemotherapy to the edge of the tissue that was removed during surgery, while largely sparing healthy brain tissue. 

The approach could potentially repurpose nanomedicines that are already used in clinical practice by administering them during this newly identified window. 

Glioblastoma remains one of the most difficult cancers to treat. More than 70% of patients undergo surgery, yet the disease almost invariably returns because infiltrating tumour cells cannot be completely removed. Average survival remains around 12–18 months despite advances in surgery, radiotherapy and chemotherapy. 

Dr Thomas Kisby, who is co-lead on the study at The University of Manchester said: “For the first time, we’ve shown that glioblastoma surgery briefly exposes a vulnerability we can exploit. If treatment is timed during specific windows we identified, it is able to halt the disease significantly before it regrows. We suggest that the hours and days immediately after surgery may hold the key to stopping glioblastoma from returning. It also raises the possibility that other established medicines could be redeployed in smarter, more strategic ways.”