Gliomas Diagnostic Criteria and Prognosis

Staging and Prognosis

• IDH-mutant and 1p/19q-codeleted oligodendrogliomas are associated with favourable response to therapy and median survival times of > 10 years.
• Patients with CNS WHO grade 3 IDH-mutant and 1p/19q-codeleted oligodendroglioma who participated in prospective clinical trials and were treated with a combination of radiotherapy and procarbazine, lomustine, and vincristine (PCV) chemotherapy showed a median survival of ≥ 14 years.

Prognostic Factors

• Younger patient age at diagnosis, frontal lobe location, presentation with seizures, high postoperative Karnofsky score, and macroscopically complete surgical removal are associated with a more favourable outcome.
• High mitotic count (≥ 2.5 mitoses/mm^2) is linked to shorter PFS and OS in IDH-mutant and 1p/19q-codeleted CNS WHO grade 3 oligodendrogliomas.
• The presence of microvascular proliferation and/or necrosis is of prognostic significance in cases lacking CDKN2A homozygous deletion.

CNS WHO Grading

• Older studies reported CNS WHO grade as an independent predictor of survival for patients with oligodendroglial tumours.
• Recent studies have shown that patients with grade 2 tumours had longer survival times than those with grade 3 tumours.

Treatment

• The optimal postoperative treatment of patients with IDH-mutant and 1p/19q-codeleted oligodendrogliomas of CNS WHO grade 2 is a matter of ongoing discussion.
• Radiotherapy and chemotherapy are often deferred until tumour progression in patients with CNS WHO grade 2 tumours.
• Patients with symptomatic and progressive tumours, with CNS WHO grade 3 tumours, or with large residual tumours after surgery usually receive immediate further treatment with radiotherapy and/or chemotherapy.
• Adjuvant radiotherapy prolonged PFS but not OS in patients with progressive CNS WHO grade 2 gliomas.
• Long-term follow-up data from randomized trials showed a major increase in OS after radiotherapy plus PCV chemotherapy in patients with CNS WHO grade 3 oligodendrogliomas.

Staging and Prognosis

• IDH-mutant and 1p/19q-codeleted oligodendrogliomas are associated with favourable response to therapy and median survival times of > 10 years.
• Patients with CNS WHO grade 3 IDH-mutant and 1p/19q-codeleted oligodendroglioma who participated in prospective clinical trials and were treated with a combination of radiotherapy and procarbazine, lomustine, and vincristine (PCV) chemotherapy showed a median survival of ≥ 14 years.

Prognostic Factors

• Younger patient age at diagnosis, frontal lobe location, presentation with seizures, high postoperative Karnofsky score, and macroscopically complete surgical removal are associated with a more favourable outcome.
• High mitotic count (≥ 2.5 mitoses/mm^2) is linked to shorter PFS and OS in IDH-mutant and 1p/19q-codeleted CNS WHO grade 3 oligodendrogliomas.
• The presence of microvascular proliferation and/or necrosis is of prognostic significance in cases lacking CDKN2A homozygous deletion.

CNS WHO Grading

• Older studies reported CNS WHO grade as an independent predictor of survival for patients with oligodendroglial tumours.
• Recent studies have shown that patients with grade 2 tumours had longer survival times than those with grade 3 tumours.

Treatment

• The optimal postoperative treatment of patients with IDH-mutant and 1p/19q-codeleted oligodendrogliomas of CNS WHO grade 2 is a matter of ongoing discussion.
• Radiotherapy and chemotherapy are often deferred until tumour progression in patients with CNS WHO grade 2 tumours.
• Patients with symptomatic and progressive tumours, with CNS WHO grade 3 tumours, or with large residual tumours after surgery usually receive immediate further treatment with radiotherapy and/or chemotherapy.
• Adjuvant radiotherapy prolonged PFS but not OS in patients with progressive CNS WHO grade 2 gliomas.
• Long-term follow-up data from randomized trials showed a major increase in OS after radiotherapy plus PCV chemotherapy in patients with CNS WHO grade 3 oligodendrogliomas.