Study population
We retrospectively reviewed the charts of children ages 3 to 18 years
with histopathologically confirmed MB at the INCA in Rio de Janeiro,
Brazil. The inclusion criteria was patients with confirmed diagnosis of
MB between January 1997 through December 2016, with ages 3-18 years. The
sample was limited to patients who received full adjuvant tratement at
INCA, therefore we excluded patients who had previously received
chemotherapy or radiation therapy elsewhere. Patients with surgeries in
other hospitals were included. An initial search revealed 134 patients
who met inclusion criteria. After 20 patients being excluded (5 due to
missing data; 6 due to lack of any treatment besides surgery, because of
clinical conditions; 5 due to treatment in another institution; 4 with
admission just for radiation therapy), a total of 114 patients were
included for analysis. The study was approved by the Hospital ethics
committee.