SEATTLE -- For patients with drug-refractory epilepsy who are eligible for surgical treatment, their outcomes end up better than continuing on medical therapy in most cases, two new studies suggested.
In the first study, which was based on published data from various sources, researchers led by , of Boston Children's Hospital calculated that the average 10-year-old undergoing surgery for drug-refractory temporal lobe epilepsy has a life expectancy of 55.2 additional years -- versus 49.3 years for those managed with drug therapy.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
Results were similar for modeled outcomes in patients with extratemporal lobe epilepsy, he reported here at the American Epilepsy Society's (AES) annual meeting, with a nearly 6-year extension in life expectancy with surgical treatment.
A second study by researchers at the Cleveland Clinic, reviewing outcomes of 36 children with Lennox-Gastaut syndrome, found that 15 became seizure-free (shortly after surgery in most cases) and another nine had reductions in seizure frequency in excess of 90%. An additional 10 patients showed reductions of 50% to 90%.
Although the study did not have a medically managed control group, senior investigator , said at an AES press briefing that these outcomes could not have been achieved solely with drug therapy.
He said the findings were important because it is only recently that children with Lennox-Gastaut syndrome have not been considered candidates for surgical therapy.
Of the 36 patients included in the study, 21 had undergone hemispherectomy while the other 15 had received lobar or multilobar resections. Patients receiving vagal nerve stimulator implants or corpus callosotomy were excluded from the analysis. Mean follow-up was a little less than 2 years, ranging from 6 months to more than 6 years.
The Boston Children's study was a modeling effort using data on mortality in patients with and without refractory epilepsy over their lifetimes, as well as on mortality associated with the surgical procedures usually performed for epilepsy treatment. The model also included data on the likelihood of achieving seizure freedom after surgery and on recurrence of regular seizures after initially successful surgery, all from previously published studies.
Computer simulations indicated that, for a cohort of 10-year-olds with temporal lobe epilepsy, 92.8% would benefit more from surgery than medical management in terms of overall life expectancy. In other forms of epilepsy, surgery would be optimal for 88%.
Sánchez Fernández said a sensitivity analysis suggested that perioperative mortality rates would have to be about 10% before medical management would become the better option for most patients.
Both studies reinforce what epileptologists have been saying for some time, which is that surgery is a curative option whereas medical management is not, and that surgery should be considered -- and discussed with patients (or their parents) -- when drug therapy is not providing seizure freedom.
Both Moosa Naduvil and , senior investigator on the Boston Children's study, said that parents are usually receptive to surgical therapies when offered for their children with drug-resistant epilepsy.
Although there remains a minority of patients who don't benefit from these procedures, adverse effects from surgery are infrequent and parents tend to favor the prospect of cure or near-cure offered with surgery, as opposed to the indefinite daily pill-taking that is medical management.
Loddenkemper noted that perisurgical mortality rates are now at or below 1%, and Moosa Naduvil said that surgery -- even with hemispherectomy, a radical procedure -- seldom leads to cognitive or behavioral impairments relative to baseline. He noted as well that Lennox-Gastaut syndrome and other severe seizure disorders in children have their own adverse cognitive effects, which surgery usually doesn't worsen and can reverse.
Disclosures
Neither study had commercial funding. Authors reported no relevant relationships with industry.
Primary Source
American Epilepsy Society Annual Meeting
Suwanpakdee P, et al "Seizure outcomes after resective epilepsy surgery in children with Lennox-Gastaut syndrome" AES 2014; Abstract 1.362.
Secondary Source
American Epilepsy Society Annual Meeting
Sanchez Fernandez I, et al "Management of children with refractory epilepsy. A decision analysis comparing medical versus surgical treatment" AES 2014; Abstract A.05.