LIMBIC AND NEOCORTICAL GLIOMAS ASSOCIATED WITH INTRACTABLE SEIZURES -A DISTINCT CLINICOPATHOLOGICAL GROUP

THE AUTHORS STUDIED 65 patients with intractable seizures and glial tu mors who were treated between 1978 and 1991. Most of the tumors were i n the temporal (63%) or occipital lobe (18%) and were commonly found i n limbic or perilimbic neocortical locations. The majority of these gl iomas (83%) involved the gray matter of allocortex, neocortex, or tran sitional cortex. These tumors spanned a wide range of glial differenti ation: Most (61%) were low-grade astrocytomas, but 17% were histologic ally malignant. However, their biological behavior was strikingly indo lent, as suggested by a stable clinical history during many years of c hronic seizures (mean, 15 yr). The median follow-up time since the ons et of symptoms in these patients was 17.2 years, and only one patient in the entire series died from the tumor. The mainstay of the surgical treatment was resection of the gliomas to histologically confirmed, t umor-free margins. The resection was not guided by intraoperative elec trocorticography. Of the 60 patients who had a postoperative follow-up of more than 1 year, 82% were seizure free. Of the 31 patients who ha d auras with their seizures, 87% did not retain their auras postoperat ively. Of the patients who were rendered seizure free, only one patien t continued to have auras. Failure in seizure control was associated w ith an incomplete resection of the lesion. In patients with temporal l obe tumors, seizure outcome was not significantly related to the exten t of medial temporal resection. It is suggested that limbic and perili mbic gliomas associated with intractable seizures constitute a distinc t clinicopathologic group of glial tumors that involve the gray matter , arise in a young host, and exhibit stable biological behavior over m any years. Surgical treatment that includes complete resection of thes e tumors can achieve excellent seizure control.