Medulloblastomas develop in the cerebellum, the lower rear part of the brain that controls movement, balance, posture, and coordination. It is a grade IV, high-grade tumour that generally affects children under the age of 14.
Medulloblastoma account for up to around 20% of all childhood central nervous system (CNS) tumours. They tend to be fast-growing tumours and often spread to other parts of the brain or spinal cord. It is now recognised that there are four main distinct subgroups of medulloblastoma called WNT medulloblastoma, Sonic Hedgehog (SHH) medulloblastoma, Group 3 medulloblastoma and Group 4 medulloblastoma.
Alarmingly there have been significantly increasing trends in incidence rates of Medulloblastoma which have increased by 1.4% per year on average over the past three decades, this may initially sound like a small percentage but in total it equates to a shocking 58% increase over a thirty-five-year period. (Australian Childhood Cancer Registry, 2020)
Sadly, the reasons behind this trend are unclear: advances in diagnostic technology and increasing population may very slightly contribute.