Researchers go deep to understand treatment response

Medulloblastoma is among the most common malignant childhood brain tumors. St. Jude was part of a 10-year clinical trial for this type of cancer. The study was organized by the Children’s Oncology Group. It enrolled patients ages 3–21 with average-risk disease. St. Jude scientists analyzed tumor samples from the trial.

This included whole exome sequencing and methylation profiling. The approaches helped scientists determine each patient’s molecular group. Prior research at St. Jude found medulloblastoma has four molecular groups. The groups are WNT, SHH, Group 3 and Group 4.

Breaking down the trial data by molecular group shows differences in how patients respond to treatment. Some subgroups may be spared some radiation. Others need such treatment. The findings will affect the design of new clinical trials.

“These results show the importance of understanding how each molecular group responds to therapy,” said Paul Northcott, PhD, of St. Jude Developmental Neurobiology.

Journal of Clinical Oncology published this work.