These gliomas tend to occur more frequently in children.
Pilocytic Astrocytoma (Grade I)
These grade I tumours are most commonly diagnosed in children. They are slowly growing and have a benign behaviour.
The main treatment approach for these tumours is surgery. A gross total resection should be obtained. If residual disease is present, repeat surgery is indicated if safe.
Radiotherapy may be used if further surgery is not possible. A dose of 50.4 Gy in 28 fractions is used. The decision for radiotherapy should take into account the age of the patient and the potential for further surgery.
Myxopapillary Ependymoma (Grade I)
An uncommon tumour even amoung ependymomas, with a median age at presentation of 36. Surgery is the mainstay of treatment and radiotherapy is usually not indicated.
Ependymoma (Grade II)
Ependymomas often present in young children (posterior fossa most commonly); they are less common in adults but make up 50-60% of primary spinal cord tumours. Rare cases of the posterior fossa may extk Widespread dissemination throughout the CSF is possible but uncommon (<10%).
Surgery
Surgical excision is essential but difficult due to the location of these tumours. The surgeon must take into account the benefit of complete resection compared to the potential sequelae of the treatment; patients who
Radiotherapy
Radiotherapy is offered for all ependymoma cases; it may be delayed for children under 3 years. The total dose is 54 Gy.
In patients with tumour cells within the CSF, or with distant CNS metastases, craniospinal irradiation is offered (36 Gy in 20#). A boost to the tumour bed and any macroscopic sites of disease follows (to 54 Gy).
In the absence of other guidelines, I would imagine fields are similar to those used for Grade II astrocytomas.
Chemotherapy
Systemic therapy only has a role in young children
Anaplastic Ependymoma (Grade III)
These tumours are of higher grade than ependymomas due to their histological features. They are associated with an earlier onset.
Management
Management is similar to ependymoma, except that a dose of 60 Gy is used instead of 54 Gy.
Diffuse Pontine Glioma (Grade II-IV; rarely biopsied)
This designtation is not present in the WHO Classifiaction of Brain Tumours. These tumours are highly aggressive and are unresectable.
Radiotherapy
These tumours are treated as per high grade gliomas (although dose is limited due to the location within the brainstem). The PTV is the enchancing tumour on MRI with a 2 cm expansion. Regardless of treatment the outcome is poor.
Localised Brainstem Glioma (Grade II-IV)
These are gliomas that occur in the brainstem as a discrete lesion. They typically occur in older patients.
Surgery
If possible, surgery is the ideal treatment.
Radiotherapy
Radiotherapy is reserved for unresectable tumours or if gross total resection is not acheived.
Optic Glioma
These tumours most commonly occur in children, often in patients with mutation in the NF1 gene (neurofibromatosis type 1). The gliomas are usually low grade (pilocytic astrocytoma) in children but may be of higher grade in adults.
Management in Children
Management depends on the site of disease and symptoms. Observation is possible for small lesions with serial MRI. If patients have already lost vision then surgery is indicated. If progression occurs and vision is still present, radiotherapy is the treatment of choice (50.4 Gy in 28 fractions).
Chemotherapy is used in children under five to delay the need for radiotherapy (if possible). Numerous schedules are used, including carboplatin with procarbazine.
Management in Adults
Adults typically have higher grade disease (except in cases of NF1 mutation). More aggressive treatment is usually indicated.
