Daijiworld Media Network - New Delhi

New Delhi, May 13: A groundbreaking study from Stanford University has revealed that CAR-T cell therapy, a promising cancer treatment, may cause mild cognitive side effects such as forgetfulness and difficulty focusing—commonly described as "brain fog."

CAR-T cell therapy works by modifying a patient’s own T cells to better recognize and destroy cancer. While it's been a game-changer in treating aggressive cancers, the new research shows it may impact brain function, regardless of whether the cancer originates in or spreads to the brain.

Published in the journal Cell, the study involved mice with tumors in various parts of the body—including brain, skin, blood, and bone. The researchers tested the mice before and after CAR-T treatment using basic memory and navigation tasks. They found that most mice developed signs of mild cognitive impairment following therapy, even when tumors were located far from the brain.

The only exception was mice with bone cancer that triggered minimal inflammation, suggesting that cognitive issues are linked more to the immune response than the tumor location. The brain’s immune cells—microglia—were identified as central to the issue.

Lead author Michelle Monje, professor of pediatric neuro-oncology at Stanford, emphasized the need to better understand and treat this side effect. “CAR-T cell therapy is saving lives. Now, we must address the lasting effects on brain function,” she said.

Encouragingly, the team also found potential strategies to reverse these cognitive effects, hinting at future treatments that can mitigate brain fog without compromising cancer care outcomes.