Niigata, Japan – A group led by the Department of Neurosurgery, Brain Research Institute, Niigata University succeeded in the diagnosis of leptomeningeal disease in diffuse midline gliomas by detecting H3K27M-mutant droplets from circulating tumor DNA of cerebrospinal fluid taken from these patients. In two patients, leptomeningeal disease was diagnosed earlier than with traditional methods such as MRI and cerebrospinal fluid cytology. In one patient, long term survival after the diagnosis of leptomeningeal disease by early and aggressive intervention including surgery, radiation, and intrathecal delivery of chemotherapeutic agents led to long term survival.
A team led by Dr. Manabu Natsumeda used droplet digital PCR, a highly sensitive PCR system, to detect trace amounts of circulating tumor DNA from the cerebrospinal fluid of these patients. "We found that detecting circulating tumor DNA in the cerebrospinal fluid of diffuse midline glioma patients was more difficult than other brain tumor patients such primary central nervous system lymphoma and glioblastoma. However, when we were able to detect mutant tumor DNA, often the tumor had already spread to the cerebrospinal fluid, causing leptomeningeal disease. We think that early diagnosis and treatment of leptomeningeal disease in diffuse midline gliomas can improve survival." explains Dr. Natsumeda. The results of the study were published online in journal Pediatric Blood and Cancer on January 9, 2025.