Brain and Spinal Cord Tumours

Introduction Brain and spinal cord tumours are increasingly being diagnosed in Africa and other developing countries as more centres acquire more sophisticated and less invasive diagnostic facilities. Improvement in the number and expertise of medical personnel also plays a significant role. In addition, advances in anaesthesia and surgical techniques have allowed for increased survival of children with these otherwise dismal clinical conditions. However, the situation in Africa is still far from the ideal, that obtains in the developed nations because only very few centres have the facilities and manpower to manage these conditions. Even in developed centres, however, the poor prognoses of some tumour types have not changed despite all the advances.1 Brain tumours are much more common than spinal tumours; this is more so in the paediatric age group. Available data show brain tumours as the second most common tumour after leukaemia (20%), and the most common solid paediatric tumours.2,3,4 Brain tumours comprise 40–50% of all tumours.5 One-quarter of all childhood cancer deaths is caused by brain tumours.1 Although paediatric brain tumours are predominantly infratentorial (60%), the location of tumours depends highly on age. Children under 6 months of age are more likely to have a supratentorial tumour (75%). The nature of the tumour also depends on location as well as age. In the infratentorial region, there is a relatively equal incidence of primitive neuroectodermal tumour (PNET); most commonly, medulloblastoma); brain-stem gliomas; and pilocytic astrocytomas. In the supratentorial region, astrocytomas are significantly more common. Concerning age, congenital tumours presenting in neonates are more likely to be neuroectodermal in origin, with teratomas being most common, whereas in older children, astrocytomas, PNET, and ependymomas predominate. Some glial tumours, such as mixed gliomas, are unique to children. They are located more frequently in the cerebellum (67%) and are usually benign.