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.