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[IDH1 mutation and MGMT expression in astrocytoma and the relationship with prognosis after radiotherapy]
Mengwan Jiang1, Xianghui Dong1, Jiayao Li1
1Department of Pathology, Harbin Medical University First Hospital, Harbin 150001, China.
Objective:
To study the correlation between IDH1 mutation, MGMT expression, clinicopathologic features and post-radiotherapy prognosis in patients with astrocytoma.
Methods:
Detection of IDH1 mutation and MGMT expression was carried out in 48 cases of astrocytoma (WHO grade II to III) by EnVision method with immunohistochemical staining. Follow-up data, including treatment response and overall survival time, were analyzed.
Results:
The rates of IDH1 mutation and MGMT expression in astrocytomas were 62.7% (30/48) and 47.9% (23/48), respectively. There was a negative correlation between IDH1 mutation and MGMT expression (r = -0.641, P < 0.01). The age of patients with IDH1 mutation was younger at disease onset. The IDH1 mutation rate in patients with WHO grade II astrocytoma was higher than that in patients with WHO grade III tumor (P < 0.05). The age at onset was an independent factor affecting the expression of mutant IDH1. After radiotherapy, patients with IDH1 mutation+/MGMT- tumor carried a longer overall survival time than patients with IDH1 mutation-/MGMT+ tumor (P < 0.05).
Conclusions:
There is a correlation between IDH1 mutation and MGMT expression in WHO grade II to III astrocytoma. Age at onset is an independent factor affecting the expression of mutant IDH1. Tumors with IDH1+/MGMT- pattern show better response to radiotherapy than tumors with IDH1-/MGMT+ pattern. Detection of IDH1 mutation and MGMT protein expression can provide some guidance in choice of treatment modalities in patients with astrocytoma.
Insights
Isocitrate dehydrogenase 1 (IDH1) mutation and O-6-methylguanine-DNA methyltransferase (MGMT) expression correlate in astrocytoma. IDH1+/MGMT- tumors show better radiotherapy response than IDH1-/MGMT+ tumors, guiding treatment decisions.
Area of Science:
- Neuro-oncology
- Molecular diagnostics
- Cancer genetics
Background:
- Astrocytomas are primary brain tumors with variable prognosis.
- IDH1 mutations and MGMT expression are key molecular markers influencing treatment response and survival.
- Understanding their interplay is crucial for personalized therapy in astrocytoma.
Purpose of the Study:
- To investigate the correlation between IDH1 mutation status and MGMT expression in astrocytomas (WHO grades II-III).
- To analyze the relationship between these markers, clinicopathologic features, and post-radiotherapy prognosis.
- To assess the potential of these markers in guiding treatment strategies.
Main Methods:
- Immunohistochemical staining was used to detect IDH1 mutations and MGMT expression in 48 astrocytoma samples.
- Clinicopathologic data and follow-up information on treatment response and overall survival were collected and analyzed.
Main Results:
- IDH1 mutations were found in 62.7% and MGMT expression in 47.9% of cases.
- A significant negative correlation was observed between IDH1 mutation and MGMT expression (r = -0.641, P < 0.01).
- Patients with IDH1 mutation+/MGMT- tumors exhibited longer overall survival post-radiotherapy compared to those with IDH1 mutation-/MGMT+ tumors (P < 0.05).
Conclusions:
- IDH1 mutation and MGMT expression are correlated in WHO grade II-III astrocytomas.
- Age at onset is an independent factor influencing IDH1 mutation expression.
- The IDH1+/MGMT- molecular pattern predicts a better response to radiotherapy, informing therapeutic choices.
