Researchers identify brain cancer weakness that could prevent relapse

Studies conducted on mice have identified a brief window after surgery for incurable brain cancer during which drugs can cross the brain's protective barrier and reach remaining cancer cells that are likely to cause the disease to return.

Surgery to remove glioblastoma tumors is typically performed within days of diagnosis, followed by chemotherapy and radiation therapy four to six weeks later. Some cancer cells inevitably remain, and this delay allows them time to grow. Chemotherapy and radiation have limited effectiveness in eliminating these residual cells, which is why tumors often recur.

Researchers found that after removing glioblastoma tumors in mice, the area where the tumor was excised—known as the resection margin—experienced disruption of the blood-brain barrier in the first hours after surgery, and again 48 to 72 hours later.

According to a report published in the journal Science Translational Medicine, drug-carrying nanoparticles were able to accumulate at the resection margin during these periods, which is the area most likely for tumors to return.

During the times when the blood-brain barrier was most disrupted after surgery, delivering nanoparticles loaded with the chemotherapy drug doxorubicin was more effective, helping to reduce tumor recurrence.

Dr. Thomas Kisby, a co-author of the study from the University of Manchester in the UK, said in a statement, "For the first time, we have shown that glioblastoma surgery briefly exposes a vulnerability we can exploit."

He added, "If treatment is synchronized within the specific time windows we identified, it can significantly suppress the disease before it regrows."