Correspondence regarding "Epidemiology, management and treatment outcome of medulloblastoma in Singapore".

Dear Editor, We read with some disquiet the article published by your journal entitled “Epidemiology, Management and Treatment Outcome of Medulloblastoma in Singapore” by Chan et al.1 It succinctly reviewed the 39 paediatric patients with medulloblastoma seen over a 9-year period in Singapore, and made 2 statements: 1. The clinical outcomes seen “were inferior to reported outcomes in established centres in the world, “ and 2. “It is uncertain if some patients received suboptimal treatment by current standards” because the radiotherapy was not necessarily risk-adapted. However, before these 2 points are accepted, it might be instructive to take a closer look at the data and compare the results of published trials with similar patient characteristics, and briefly evaluate risk-adapted treatment in medulloblastoma. In the current study, the 5-year overall survival in the cohort without metastases was 78.7%, similar to the 76.7% reported by the International Society of Paediatric Oncology/ UK Children’s Cancer Study Group PNET-3 Study2 for non-metastatic patients receiving postoperative radiotherapy and chemotherapy. Similarly, the 28.8% 5-year event-free survival for patients under 36 months of age compares well with the results from the Phase II French Society of Paediatric Oncology (SFOP)3 trial, in which patients aged under 5 years received postoperative chemotherapy but no radiotherapy. They reported a 5-year progression-free survival ranging from 6% to 29%. The authors also raised the issue of risk-adapted radiotherapy. Many centres, including ours, currently stratify patients into average-risk or high-risk groups. Those diagnosed after the age of 3 years with non-metastatic and totally, or near totally, resected disease (<1.5 cm2 on postoperative magnetic resonance imaging) are considered to be at average risk. All other patients who do not meet these criteria are classified as high-risk. For average-risk patients, some centres have in recent years lowered the radiotherapy dose received by the craniospinal axis from 35-36Gy to 23.4Gy, though some European centres have kept the dose at 35Gy.4 The Pediatric Correspondence Regarding “Epidemiology, Management and Treatment Outcome of Medulloblastoma in Singapore”