The most common malignant brain tumors in children, medulloblastomas, are usually incurable if they recur. Even with surgery, chemotherapy, radiation and stem cell transplantation, children with recurrent medulloblastoma have a two-year overall survival rate of less than 20%.To improve these odds, MD Anderson researchers are testing a new therapy that infuses natural killer (NK) cells directly into the brain. The clinical trial is currently enrolling patients younger than age 22 who are diagnosed with recurring malignant brain tumors like medulloblastoma that originate in the posterior fossa — the small space in the skull found near the brain stem and the cerebellum.
These tumors tend to spread to other parts of the brain and to the spinal cord.
“Medulloblastomas recur in 20 to 30% of pediatric patients,” said Soumen Khatua, M.D., chief of Pediatric Neuro-oncology at MD Anderson and principal investigator of the trial. “We need to find novel therapies for posterior fossa tumors that can have a meaningful effect on survival.”
During the study, natural killer cells are harvested from each patient’s own blood. The cells are multiplied, then frozen until the time of infusion when they are fed back into the patient’s brain through a catheter.
Patients receive three infusions per week for three weeks followed by one week of rest. Three months after the completion of treatment, patients undergo magnetic resonance imaging to assess the tumor response.
More than 50 infusions have been performed so far, Khatua said. Preliminary results are not yet available, but laboratory tests performed prior to the clinical trial showed that natural killer cells had antitumor activity against medulloblastoma and other posterior fossa tumors.
Read more about this study for childhood brain tumors in Oncolog.