TURKISH JOURNAL OF ONCOLOGY 2021 , Vol 36 , Num 2
Impact of Seizures and Anti-epileptic Drug Use on Survival in Patients with World Health Organization Grade II Glioma
Sezin YÜCE SARI1,Ahmetcan ÇAĞLAR2,Gözde YAZICI1,Mustafa CENGİZ1,Faruk ZORLU1
1Department of Radiation Oncology, Hacettepe University Faculty of Medicine, Ankara-Turkey
2Department of Radiotherapy, Hatay State Hospital, Hatay-Turkey
DOI : 10.5505/tjo.2021.2660 OBJECTIVE
Epileptic seizures are prognostic for low-grade gliomas. However, the impact of anti-epileptic drug use (AED) on outcomes is unclear. We aimed to evaluate the impact of epileptic seizures and AED use on tumor control and survival rates after radiotherapy (RT) in patients with World Health Organization Grade II glioma.

METHODS
A total of 182 patients who underwent RT either early after surgery or in case of progression were retrospectively evaluated. The primary end point was the impact of seizures on overall survival (OS), local control (LC), and progression-free survival (PFS) rates. The secondary end point was the impact of AED use on these rates.

RESULTS
Median follow-up was 80 months. The number of patients with epileptic seizures at the time of diagnosis was 113 (62%). The 2-, 5-, and 10-year OS, LC, and PFS rates were significantly higher in patients with seizures (p=0.022 and p=0.001, respectively). When patients that did and did not use AED were compared, OS, LC, and PFS rates were similar. Besides, using AEDs in patients without seizures did not affect the OS, LC, and PFS rates. Carbamazepine use was associated with higher OS and PFS rates with a non-significant increase in LC. Phenytoin use yielded an increase in the PFS and LC rates in the first 2 years which turned to opposite after the 6th year.

CONCLUSION
Seizures at the time of diagnosis and using AEDs for the treatment of seizures both increase survival rates in patients with Grade II glioma. Patients using carbamazepine had increased survival rates. Keywords : Anti-epileptic drug; epilepsy; glioma; radiotherapy