ABSTRACT Extranodal NK/T-cell lymphoma, nasal type (ENKTL-NT) is a rare type of Non-Hodgkin’s lymphoma, which usually presents with extranodal involvement and affects the nasal/upper aerodigestive tract in the classical presentation. Herein, we report the case of a 31-year-old, previously healthy, male patient diagnosed with ENKTL-NT with the involvement of the lung parenchyma and heart. Unfortunately, due to the rapid disease progression, the diagnosis was performed only at the autopsy. The authors highlight the rare clinical presentation of this type of lymphoma, as well as the challenging anatomopathological diagnosis in necrotic samples.

RESUMO. A encefalite de Rasmussen (ER) é um distúrbio clássico da faixa etária infantil e apenas 10% dos casos são descritos em adultos. Trazemos dois casos comprovados de ER em idosos, com idade acima de 55 anos de idade. Objetivo: Descrever as características clínicas, evolução, avaliação diagnóstica, achados neuropatológicos e tratamento da ER em dois casos clínicos com mais de 55 anos de idade. Além disso, atentar para o declínio cognitivo progressivo como uma característica importante na apresentação ER idosos em associação à epilepsia focal. Métodos: Série de casos de dois Hospitais Terciários em São Paulo, Brasil. Dados retrospectivos foram coletados de um caso. Resultados: Dois indivíduos do sexo masculino com idade >55 anos e apresentação clínica de epilepsia focal associada a deterioração cognitiva progressiva. Conclusão: A ER pode ser considerada a causa do declínio cognitivo progressivo em idosos, especialmente se for descrita epilepsia focal associada a achados assimétricos em neuroimagem.

ABSTRACT. Rasmussen encephalitis (RE) is a classic disorder in the child age group, and only 10% of cases are described in adults. We bring two proven cases of RE in older adults aged over 55 years. Objective: To describe the clinical characteristics, progression, diagnostic assessment, neuropathological findings, and treatment of RE in two clinical cases of patients over 55 years of age. Furthermore, we address progressive cognitive decline as an important feature of the RE presentation in older adults in association with focal epilepsy. Methods: This is a case series from two tertiary hospitals from São Paulo – Brazil. Retrospective data were collected from one case. Results: Two male individuals aged >55 years with clinical presentation of focal epilepsy along with progressive cognitive deterioration. Conclusions: RE could be considered the cause of progressive cognitive decline in older adults, especially if focal epilepsy is described together with asymmetrical neuroimaging findings.