RESUMEN
A palette of copy number changes in long-term epilepsy-associated tumors (LEATs) have been reported, but the data are heterogeneous. To better understand the molecular basis underlying the development of LEATs, we performed array-comparative genomic hybridization analysis to investigate chromosomal imbalances across the entire genome in 8 cases of LEATs. A high number of aberrations were found in 4 patients, among which deletions predominated. Both whole-chromosome and regional abnormalities were observed, including monosomy 19, deletion of 1p, deletions of 4p, 12p, and 22q, and gain of 20p. The common altered regions are located mainly on chromosomes 19 and 4p, identifying genes potentially involved in biological processes and cellular mechanisms related to tumorigenesis. Our study highlights new genomic alterations and reinforces others previously reported, offering new molecular insights that may help in diagnosis and therapeutic decision-making.
Asunto(s)
Epilepsia , Neoplasias , Aberraciones Cromosómicas , Hibridación Genómica Comparativa , Epilepsia/genética , Genómica , Humanos , Monosomía , Hibridación de Ácido NucleicoRESUMEN
INTRODUCTION: Over recent decades, brain resection for drug-resistant epilepsy has proven to be a valuable treatment option. The histopathological classification was of paramount value for patient management. The aims of this study were to characterize our resective epilepsy surgical series including the histopathological diagnoses and to understand the differences in clinical practice between two different periods of our epilepsy surgical programme. MATERIAL AND METHODS: We performed a retrospective cohort study, including patients with drug-resistant epilepsy that underwent resective surgery between 1997 and 2021 in the Coimbra University Hospital Centre. Histopathological diagnoses were classified into seven major conventional categories. For comparison purposes, the cohort was divided into two consecutive periods of 12 years. RESULTS: A total of 259 patients were included, from which 228 (88%) were adults at the time of surgery. The median disease duration prior to surgery was 14 (interquartile range 23) years. Fifty-five (21%) patients performed pre-surgical invasive work-up. The temporal lobe was the most frequently operated region (73%). Major and minor post-surgical complications were identified in 21 (8%) patients. A reduction in the number of antiepileptic drugs was possible in 96 (37%) patients after surgery. The most common histopathological diagnosis was hippocampal sclerosis, but among children it was long-term epilepsy associated tumour. Long-term epilepsy associated tumours, hippocampal sclerosis and vascular malformations had the best post-operative outcomes. Malformations of cortical development and glial scars had the worst outcomes. Regarding differences between the two periods, the absolute number of operated patients increased (119 versus 140), and the age at surgery was higher in the second period (p = 0.04). The number of malformations of cortical development increased (p = 0.01), but the number of other tumours (p = 0.01) and specimens with no lesion (p = 0.03) decreased in the same period. CONCLUSION: This study is in line with contemporaneous research, reinforcing the previous knowledge on the underlying structural aetiologies, clinical practice, and surgical outcomes over more than two decades of experience. Our data provide realistic expectations about epilepsy surgery and highlight the need for further improvements in diagnosis and treatment paradigm for people with chronic epilepsy.
Introdução: Nas últimas décadas, a cirurgia ressectiva demonstrou ser uma opção valiosa no tratamento da epilepsia farmacorresistente. A classificação histopatológica foi de grande importância na orientação do doente. Os objetivos deste estudo foram caracterizar a nossa série de cirurgia de epilepsia ressectiva incluindo os diagnósticos histopatológicos, e compreender as diferenças na prática clínica entre dois períodos diferentes do programa de cirurgia da epilepsia. Material e Métodos: Realizou-se um estudo de coorte retrospetivo, incluindo doentes com epilepsia farmacorresistente submetidos a cirurgia ressectiva entre 1997 e 2021 no Centro Hospitalar e Universitário de Coimbra. Os diagnósticos histopatológicos foram classificados em sete categorias. Para análise comparativa, a coorte foi dividida em dois períodos consecutivos de 12 anos. Resultados: Um total de 259 doentes foram incluídos, sendo 228 (88%) adultos aquando da cirurgia. A mediana da duração da doença antes da cirurgia foi de 14 (amplitude interquartil 23) anos. Cinquenta e cinco (21%) doentes realizaram investigação invasiva pré-cirúrgica. O lobo temporal foi a região mais frequentemente operada (73%). Complicações pós-cirúrgicas major e minor foram identificadas em 21 (8%) doentes. Uma redução no número de antiepiléticos foi observada em 96 (37%) doentes após a cirurgia. O diagnóstico histopatológico mais comum foi a esclerose do hipocampo, mas nas crianças foi o tumor associado a epilepsia de longa duração. Tumores associados a epilepsia de longa duração, esclerose do hipocampo e malformações vasculares tiveram os melhores resultados pós-operatórios. Malformações do desenvolvimento cortical e cicatrizes gliais tiveram os piores resultados. Relativamente às diferenças entre os dois períodos, o número absoluto de doentes operados aumentou (119 versus 140), e a idade aquando da cirurgia foi maior no segundo período (p = 0,04). O número de malformações do desenvolvimento cortical aumentou (p = 0,01), mas o número de outros tumores (p = 0,01) e amostras sem lesão (p = 0,03) diminuiu no mesmo período. Conclusão: Este estudo está de acordo com a literatura atual, reforçando o conhecimento prévio sobre as etiologias estruturais, prática clínica e resultados cirúrgicos ao longo de mais de duas décadas de experiência. Os dados analisados fornecem expectativas realistas sobre a cirurgia de epilepsia e destacam a necessidade de melhorias no paradigma de diagnóstico e tratamento destes doentes.