Jezabel Rodriguez-Blanco, PhD, at the Medical University of South Carolina, focuses some of her research on one of the four molecular groups of medulloblastoma, known as the SHH subgroup. Researchers are now trying to find out how to use what they know about these molecular subgroups to improve treatment. Some types have better outlooks than others. Medulloblastomas are divided into 4 molecular groups based on how the tumor looks under a microscope and on which gene mutations the cells have. With recurrence, there aren’t any other effective treatment options. But for the around 30% of children whose cancer recurs, the 5-year survival is close to zero. The 5-year survival rate for medulloblastoma is about 70%. These tumors are fast growing and tend to spread through the cerebrospinal fluid, mostly to the spinal cord. They can occur at any age but most often occur in babies and young children. Medulloblastomas are the most common type of malignant brain tumor in children, though it is still considered rare, with fewer than 500 new cases diagnosed a year.