Dysembryoplastic neuroepithelial tumors: a model for examining the effects of pathology versus seizures on cognitive dysfunction in epilepsy

Sex differences in the pre and postoperative neuropsychological function of epilepsy surgery candidates

Objective: As programs expand globally, epilepsy surgery is becoming increasingly available as an effective treatment for some people with medically intractable seizures. Prospective candidates require careful neuropsychological evaluation and follow-up. The aim of this study was to examine the sex differences in neuropsychological function in presurgical presentation and postoperative outcomes in people with temporal lobe epilepsy referred for epilepsy surgery. Methods: Three hundred and seventy-two patients (202 Female; 170 Male) with a homogenous underlying pathology (hippocampal sclerosis) underwent a preoperative assessment on tests of intellectual, language, and memory function and were followed up one year after undergoing a unilateral temporal lobe resection; n = 169 Right (RTL), n = 203 Left (LTL). Results: There was no impact of sex or laterality of surgery on seizure outcome; 84% of males and 80% of females were seizure free at follow-up. Before surgery, sex effects were evident on tests of verbal memory with females performing better than males. Declines in verbal memory function following surgery were greater in females than males. Being female had a stronger association with postoperative decline on immediate prose recall (partial eta squared η2 = 0.029), than side of surgery (η2 = 0.018) albeit with a small effect size. Conclusions: There are subtle but significant sex differences in the neuropsychological profiles of people with temporal lobe epilepsy, before and following surgery. Whilst females generally perform better than males on tests of verbal memory function before surgery they demonstrate greater post-operative declines on these measures following surgery.

The who, what, when and why of cognitive difficulties in epilepsy

Cognitive complaints are very common in people diagnosed with epilepsy. These difficulties are often another manifestation of the same pathology responsible for seizures. They can be further exacerbated by treatments aimed at seizure control. Other common comorbidities of epilepsy such as low mood and elevated anxiety can also contribute to cognitive complaints. There is surprisingly little overlap between memory complaints and performance on formal memory tests in this population. This article examines the multifactorial and heterogeneous nature of cognitive difficulties in epilepsy and makes the case for the provision of basic psychoeducation as the foundation for all interventions aimed at ameliorating these difficulties in this patient population.

Long-Term Seizure Outcomes and Predictors in Patients with Dysembryoplastic Neuroepithelial Tumors Associated with Epilepsy

OBJECTIVE

To determine the predictors and the long-term outcomes of patients with seizures following surgery for dysembryoplastic neuroepithelial tumors (DNTs); Methods: Clinical data were collected from medical records of consecutive patients of the Department of Neurosurgery of Sanbo Brain Hospital of Capital Medical University with a pathological diagnosis of DNT and who underwent surgery from January 2008 to July 2021. All patients were followed up after surgery for at least one year. We estimated the cumulative rate of seizure recurrence-free and generated survival curves. A log-rank (Mantel-Cox) test and a Cox proportional hazard model were performed for univariate and multivariate analysis to analyze influential predictors; Results: 63 patients (33 males and 30 females) were included in this study. At the final follow-up, 49 patients (77.8%) were seizure-free. The cumulative rate of seizure recurrence-free was 82.5% (95% confidence interval (CI) 71.8-91.3%), 79.0% (95% CI 67.8-88.6%) and 76.5% (95% CI 64.8-87.0%) at 2, 5, and 10 years, respectively. The mean time for seizure recurrence-free was 6.892 ± 0.501 years (95% CI 5.91-7.87). Gross total removal of the tumor and a short epilepsy duration were significant predictors of seizure freedom. Younger age of seizure onset, bilateral interictal epileptiform discharges, and MRI type 3 tumors were risk factors for poor prognosis; Conclusions: A favorable long-term seizure outcome was observed for patients with DNT after surgical resection. Predictor analysis could effectively guide the clinical work and evaluate the prognosis of patients with DNT associated with epilepsy.

The cognitive functions and seizure outcomes of patients with low-grade epilepsy-associated neuroepithelial tumors

PURPOSE

The aim of the study was to evaluate the cognitive functions and seizure outcomes of patients with low-grade epilepsy-associated neuroepithelial tumors (LEATs).

METHODS

We retrospectively reviewed the clinical data of patients who underwent preoperative neuropsychological evaluations and subsequent epilepsy surgery for LEATs. The neuropsychological results of full-scaled intelligence quotient (FSIQ) and full-scaled memory quotient (FSMQ) were analyzed, as well as the postoperative seizure outcomes.

RESULTS

Of the 138 patients included in the study, 59 patients (40.4%) were female and 47 (36.6%) patients were children. Preoperatively, 138 patients received FSIQ assessments and 30 patients (21.7%) had an intellectual deficit (FSIQ < 80 scores); 124 patients received FSMQ assessments and 32 patients (25.8%) had a memory deficit (FSMQ < 80 scores). Younger age at seizure onset (OR 0.93; P = 0.035) and discordant ictal electroencephalography (EEG) findings (OR 5.26; P = 0.001) were found to predict intellectual deficits, while abnormal hippocampus (OR 2.36; P = 0.051) as well as discordant ictal EEG findings (OR 4.03; P = 0.007) tended to cause memory deficits. During postoperative follow-up, 123 patients (90.7%) were followed up at least 12 months, and among them, 105 patients (85.4%) got seizure-free (Engel class I), while 18 patients (14.6%) were not (Engel class II-IV); longer duration of epilepsy (OR 1.01; P < 0.001) and discordant interictal EEG findings (OR 5.91; P = 0.005) were found to be related to poor seizure outcomes in patients with LEATs.

CONCLUSION

Cognitive deficits commonly occur in patients with LEATs, especially in patients with early or childhood seizures. Early surgical intervention, however, could prevent most of patients from repeated seizure onsets and thus cognitive impairments.

Neuropsychology of temporal lobe epilepsies

This chapter focuses on the neuropsychology of adults with temporal lobe epilepsy (TLE). First, a thorough description of the brain-behavior relationship characterizing focal TLE with and without hippocampal sclerosis is presented. Then, the aim and the specificity of the NPA in the care of epilepsy are described. Considering the high frequency of medically intractable TLE that can be treated by surgery, an assessment carried out in the context of pre- and postoperative evaluation is presented and discussed in light of insights from functional neuroimaging findings. Finally, we propose concluding remarks about the place of neuropsychology in the care of epilepsy in improving our understanding of the cognitive and emotional phenotypes associated with TLE.

Association of CT and MRI Manifestations with Pathology in Dysembryoplastic Neuroepithelial Tumors

Objective

To investigate the CT, MRI and pathological features of dysembryoplastic neuroepithelial tumor (DNET).

Methods

The CT and MRI features of six cases of pathologically confirmed DNET were retrospectively analyzed and compared with pathology.

Results

All six cases of DNET were solitary, and lesion in one case was located in the right parietal lobe, one case in the right frontal lobe, one case in the cerebellar vermis, one case in the right temporo-parietal occipital lobe, one case in the left basal ganglia, and one case in the pineal gland. CT and MRI showed cystic solid tumor in all six cases, of which four showed calcification. In CT images, the cystic components appeared low-density, solid nodules, septa, and cyst walls were slightly high-density, and calcifications were high-density. In MRI images, the cystic components were hypointense on T1WI and hyperintense on T2WI, solid nodules, septa and cyst walls were iso-intense or slightly hyperintense on T1WI and T2WI sequences, and calcifications were all hypointense. On enhanced scan, the cystic components were not enhanced, and the solid nodules, septa, and cyst walls were inhomogeneously enhanced.

Conclusion

The imaging manifestations of DNET are characteristic, and the combination of clinical and imaging features can greatly improve diagnostic accuracy.

Cognitive impairment in temporal lobe epilepsy: contributions of lesion, localization and lateralization

BACKGROUND

Cognitive impairment is an important comorbidity of refractory temporal lobe epilepsy (TLE). We aimed to explore the impact of (i) specific lesions, such as dysembryoplastic neuroepithelial tumor (DNET), dysplasia, or hippocampal sclerosis, (ii) focus localization (medial versus lateral) and (iii) focus lateralization (right versus left) on the neuropsychological profile of refractory TLE adult patients.

METHODS

We examined the neuropsychological characteristics of 312 adults with refractory TLE: 100 patients without hippocampal sclerosis (HS) and 212 with HS. Scores on tests of intelligence (Global IQ, Verbal IQ and Performance IQ), working memory, episodic memory (verbal and visual learning and forgetting), executive functions and language abilities were analyzed.

RESULTS

Three main factors influenced the neuropsychological profile of refractory TLE patients: (i) the lesion, patients with HS obtaining poorer cognitive performances than patients without HS and specifically DNET patients performing better than patients with HS, (ii) the focus side, that seems only relevant for verbal memory abilities which are affected in left but not right TLE patients and (iii) the localization of seizure focus, patients with medial TLE exhibiting lower memory performances than patients with lateral TLE.

CONCLUSION

Lesion, localization and lateralization are major contributors of the cognitive impairment depicted in TLE. Hippocampal sclerosis appears as the main contributor.

Avaliação Neuropsicológica em Pacientes com Tumores Cerebrais: revisão sistemática da literatura

Os tumores cerebrais (TC) são causados pelo crescimento anormal de células. As consequências dos TC podem envolver prejuízos físicos, cognitivos e emocionais. Objetiva-se identificar e descrever os prejuízos cognitivos associados aos TC, através de uma revisão sistemática da literatura. As buscas realizaram-se nas bases de dados internacionais PubMed/MEDLINE, LILACS, e SCOPUS, incluindo abstracts de artigos publicados de 2006 a 2016. Encontrou-se 501 artigos desses, 31 cumpriram os critérios de inclusão. Os TC, representam 5% das neoplasias, sendo alguns mais agressivos que outros. Apresenta-se como sintomas severos: déficits cognitivos, motores. A avaliação neuropsicológica auxilia na identificação de possíveis alterações cognitivas e no acompanhamento dos efeitos do tratamento, contribuindo para melhor qualidade de vida desses pacientes. Os resultados encontrados indicaram as Escalas Wechsler de Inteligência; Matrizes Progressivas de Raven, Figuras Complexas de Rey, Teste de Retenção Visual de Benton, e Token Test como os mais utilizados, e que evidenciaram como prejuízos os envolvendo a memória, a atenção e funções executivas. A localização mais frequente destes TC eram as regiões frontais e temporais e os gliomas o tipo de tumor mais investigado.

Cognitive features and surgical outcome of patients with long-term epilepsy-associated tumors (LEATs) within the temporal lobe

OBJECTIVE

The objective of the study was to evaluate cognitive and epilepsy-related features in 166 surgically treated patients with epilepsy with long-term epilepsy-associated tumors (LEATs) located in the temporal lobe.

METHOD

Pre- and postsurgical cognitive as well as the one-year seizure outcome of adult patients with histopathologically confirmed LEATs (28 grade-I dysembryoplastic neuroepithelial tumors (DNET), 95 grade-I gangliogliomas (GG), 24 grade-I pilocytic astrocytomas (PA), 9 grade-II pleomorphic xanthoastrocytoma (PXA), 10 grade-II diffuse astrocytoma (DA)) who underwent epilepsy surgery in Bonn/Germany between 1988 and 2012 were evaluated.

RESULTS

At baseline, tumor groups differed in regard to age at epilepsy onset and location within the temporal lobe. Postoperative seizure freedom was achieved most frequently (>77.8%) in DNET, GG, and DA, less often in PXA (62.5%) and the least in PA (56.5%). Preoperative memory was impaired in 67.1% of all patients, executive functions in 44.7%, and language in 45.5%. Patients with PA displayed the poorest cognitive performance. Individual significant memory decline that was observed in 27.1% of all patients was predicted by left-sided surgery, a mesial pathology, and extended hippocampal resection. Executive functions depended on antiepileptic drug (AED) load and remained stable (72.0%) or even improved (21.6%) after surgery. Language functions were unchanged in 89.5% of patients.

CONCLUSION

Patients with LEATs in the temporal lobe frequently show cognitive impairments. Predictors for pre- and postoperative cognition mostly correspond to what is known for temporal lobe epilepsy and resections in general. However, different tumor types appear to be associated with different cognitive and seizure outcomes with astrocytoma as the least benefitted group.