Treatment of Gliomas  

Low grade gliomas

(astrocytomas, oligodendrogliomas or oligoastrocytoma)

Surgery: The initial treatment in almost all cases
• Maximal safe resection with the aim of total excision whenever feasible.
• Open or stereotactic biopsy for very extensive and diffuse tumours or those in eloquent areas where near total excision could result in significant deficit.
• Histologic proof may not be required in diffuse pontine gliomas or Neurofibromatosis type 1 associated optic pathway gliomas.

Radiotherapy:

Most patients require RT to prevent / delay tumour progression.

Target Volume: Hypodensity on CT or hyperintense area on T2/FLAIR MRI + 1.5 - 2 cm margin
Planning: Preferably 3D CT planning, multiple beams and whenever required MLC/conformal blocks.
Dose: 54Gy in 30 fractions over 6 weeks using ICRU guidelines. For very large brain volumes or very young age, the total dose may be reduced to 45 or 50 Gy with 1.67 to 1.8 Gy per fraction.

Post operative observation with deferred radiotherapy until progression.

Indications for deferred radiation:

• Reliable for clinical / radiologic follow up

• No adverse / equivocal histology or unusual enhancement

• At any age: Completely excised tumours, confirmed on immediate or 6 week post op MRI.

• In children and young adults: Near totally or sometimes partially excised tumour in non-eloquent areas, no or minimal neurologic deficit and no mass effect.

• In adults: particularly for incompletely excised fibrillary astrocytomas (grade I and II) and oligodendrogliomas with no mass effect and no focal neurologic deficit. Patients with typical low grade astrocytomas may be screened for eligibility for MRI perfusion (rCBV) study.
  (Pignatti’s criteria are used to assist in decision making for observation: If more than 2 criteria are present then patients to be offered immediate radiotherapy, otherwise to consider for observation and to make judgment individually.  Criteria: age> 40 years, tumor > 6 cm, tumor crossing midline, neurologic deficit and presence of oligo component.)

• MIB-1 is done in Grade 2 tumors and if it is less than 6% then, to consider for observation, otherwise to offer immediate RT.

• Children < 3 years of age: Post operative chemotherapy with deferred radiotherapy till children attain 3 years. For partially excised or only biopsied tumours in critical sites such as optic pathway, hypothalamus or thalamus, or presence of neurologic deficit or mass effect: Initial chemotherapy (Packer’s regimen or ICE) for 6 – 12 months and to defer radiotherapy till the age of 3 years for minimizing the late radiation sequelae.

High grade gliomas

(anaplastic astrocytoma and glioblastoma multiforme)

Surgery:

The initial treatment in almost all cases. Extent of surgery as in low-grade glioma.

Radiotherapy:

Almost all high-grade glioma patients require radiotherapy,

Dose and fractionation: Depends upon the patient's prognosis as per the following table.

• Favorable Prognosis patients: 60Gy in 30 fractions over 6 weeks.
• Poor Prognosis patients: 45Gy in 18 fractions over 4 weeks or 35Gy in 7 fraction over 6 weeks (once weekly).

The prognostic system for high grade gliomas (Grade III & IV) is based on age & neurologic function.

*Patients who are independent (NPS 0,1) are considered as favourable prognosis, irrespective of age.

*Patients who are dependent (NPS 3,4) are considered as poor prognosis, irrespective of age.

*Patients who are Semi-dependent (NPS 2) are considered as favourable prognosis if <50 years and poor prognosis if >50 years of age.

Temozolomide

For favourable prognosis patients with Glioblastoma multiforme (grade IV), affording ones are started on concomitant temozolomide 75 mg/m2 daily (7 days a week) during radiotherapy with weekly blood count checks. These patients are reviewed at 4 weeks after RT completion and a baseline imaging (preferably MRI) is done and a blood count is repeated. Patients are then started on adjuvant temozolomide for 5 days every 28 days for 6 cycles. (150 mg/m2 for 1st and 200 mg/m2 for rest of the cycles) with blood count check before every cycle.

Treatment of Ependymomas

Low grade (any site)

Involved field RT-54 Gy in 30# (hypodensity on CT or hyperintense area on T2 MRI+ 2 cms)

High grade (any site)

Involved field RT-54 Gy in 30#

For anaplastic ependymoma, CSF cytology and MRI spine is done to rule out spinal dissemination. No need for CSI if no spinal metastasis For children and young adults, we try to use 3D conformal techniques.

Home

<Previous || Next>