RESUMO
PURPOSE: Radiation-induced pseudoprogression is a subacute clinical entity that is distinct from radiation necrosis and mimics tumor progression. Bevacizumab is a well-described treatment option for radiation necrosis, but its role in pseudoprogression is not clearly defined. METHODS: We report a case of radiation-induced pseudoprogression rescued with bevacizumab in a 20-year-old man with a biopsy-proven low-grade astrocytoma of the tectum. A review of the literature was also conducted specific to bevacizumab as a treatment for symptomatic pseudoprogression after radiotherapy for CNS tumors. RESULTS: This patient was treated with definitive intensity modulated stereotactic radiotherapy at a total dose of 54 Gy delivered in 30 daily fractions. Six weeks after radiotherapy the patient developed progressive headache, weakness and a documented deterioration in vision, which was accompanied by worsening of radiographic findings. A diagnosis of pseudoprogression was made and after limited benefit from a trial of dexamethasone, four cycles of bevacizumab were administered which resulted in rapid clinical and radiographic improvement. CONCLUSIONS: Our findings support the potential use of bevacizumab as a rescue agent for symptomatic pseudoprogression.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Lesões por Radiação/tratamento farmacológico , Radioterapia de Intensidade Modulada/efeitos adversos , Teto do Mesencéfalo/efeitos da radiação , Adulto , Neoplasias Encefálicas/patologia , Progressão da Doença , Glioma/patologia , Humanos , Masculino , Prognóstico , Lesões por Radiação/etiologia , Lesões por Radiação/patologia , Teto do Mesencéfalo/patologia , Adulto JovemRESUMO
Astrocytoma arising from the tectum of the mesencephalon is an unusual tumor that is different from other brain stem tumors in clinical features. We describe two patients with tectal low-grade astrocytoma. Each patient underwent CSF diversion and biopsy followed by radiation therapy. A review of the literature on the clinical, radiographic, and pathological findings and the management of tectal tumor is presented.
Assuntos
Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Teto do Mesencéfalo/patologia , Adolescente , Astrocitoma/radioterapia , Astrocitoma/cirurgia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Angiografia Cerebral , Pré-Escolar , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Teto do Mesencéfalo/efeitos da radiação , Teto do Mesencéfalo/cirurgia , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Derivação VentriculoperitonealRESUMO
The histochemical methods were used to study alkaline phosphomonoesterase of capillaries, glycosaminoglycanes of vascular walls, and tissular basophils of rat brain after local gamma-irradiation of the head with doses of 51.6-645 mC/kg. During the first minutes and hours after irradiation, the actively functioning capillary network lengthened and secretion of indolylamines by tissular basophils increased. It is assumed that the changes observed are compensatory.
