Clinical and molecular genetic factors affecting postoperative seizure control of 183 Chinese adult patients with low-grade gliomas

Background and purpose: Seizures are a common symptom of patients with primary brain tumors, particularly low‐grade gliomas (LGGs). Poor seizure control after surgery has a great adverse impact on quality of life in these patients. The present study aimed to identify clinical and molecular genetic factors that influence postoperative seizure control. Methods: A series of 183 LGGs were analyzed by denaturing high‐performance liquid chromatography (DHPLC) for 1p and 19q status and by immunohistochemical staining for expression of several molecular markers (P53, Ki‐67, MMP‐9 and MGMT), with particular emphasis on correlations with postoperative seizure control. Univariate and multivariate logistic regression analyses were used for statistic analysis. Results: Of the 183 patients, 134 (73.2%) patients presented with seizures. Most of oligodendrogliomas and oligoastrocytomas had LOH 1p and LOH 19q, which were rarely seen in combination in astrocytomas (P < 0.001). Oligodendroglial tumors were more likely to locate in frontal lobe (P = 0.011) and present calcification on MRI (P = 0.024). Temporal location (P = 0.014), and high expression of mutated P53 (P = 0.011) were associated with astrocytomas. Patients achieved much better seizure control after gross‐total resection (P < 0.001) than after subtotal resection. Patients without LOH 19q were more likely to have poor seizure control (P = 0.004) than those with this alteration. Ki‐67 was an independent molecular marker predicting poor seizure control (P = 0.016) if over expressed. Conclusions: Gross total resection of the tumor, LOH 19q and low Ki‐67 expression were associated with favorable seizure control after surgery for the patients with LGGs. The possible involvement of other factors should be investigated further.