Brain Cancer Begins Years Before Tumors Appear, Study Finds

Doctors may soon catch deadly brain tumors years before they become visible, thanks to a discovery that changes everything we thought we knew about how brain cancer begins.

Scientists in Korea found that IDH-mutant glioma, the most common malignant brain tumor in adults under 50, doesn't suddenly appear out of nowhere. Instead, it starts silently in normal-looking brain cells and spreads through the brain long before forming a detectable tumor.

The research team from the Korea Advanced Institute of Science and Technology and Yonsei University examined brain tissue from surgery patients. They found mutant cells hiding in areas that looked completely normal to the naked eye.

These "cells of origin" are called Glial Progenitor Cells, a type of cell that exists naturally in healthy brains. When these cells acquire a single genetic mutation, they can quietly spread throughout the brain's cortex for years before accumulating enough additional mutations to form a visible tumor mass.

The team used spatial transcriptomics, a cutting-edge technology that maps which genes are active and exactly where in the tissue. They confirmed their findings by recreating the same process in mice, watching as the same genetic mutation triggered the early steps of tumor development.

The Ripple Effect

This discovery opens doors that were previously locked. If doctors can detect these early mutant cells before they become tumors, they might prevent brain cancer from taking hold in the first place.

The finding is already creating real-world impact. A KAIST startup called Sovagen is developing an RNA-based drug to stop these tumors from evolving and coming back after treatment. Meanwhile, researchers at Severance Hospital are working on technologies to detect and control these early mutant cells through a Korea-US collaboration.

The breakthrough also solves a medical mystery. In 2018, the same research team discovered that a different type of brain cancer, IDH wildtype glioblastoma, originates from neural stem cells in a completely different part of the brain. This proves that different brain cancers have fundamentally different origins, which explains why they behave so differently and why one-size-fits-all treatments often fail.

For the thousands of young adults diagnosed with IDH-mutant glioma each year, this research brings something that's been in short supply: hope. The cancer has long frustrated doctors because it tends to return even after aggressive treatment and surgery.

The research appears in the journal Science, representing years of collaboration between world-class scientists and surgeons who refused to accept that brain tumors were inevitable once they appeared.