Gamma Knife radiosurgery for brain metastasis: review of 103 patients / Radiocirurgia com Gamma Knife para metástases cerebrais. Análise de 103 casos

Objective: To assess clinical and imaging outcomes in patients treated with Gamma Knife stereotactic radiosurgery (SRS) for brain metastasis. Methods: One hundred and three patients with 158 intracranial metastasis consecutively underwent Gamma Knife SRS between January, 2004 and December, 2006. The results were based on last imaging and the date of the last visit. Average age of the patients was 56 years (range 32-84 years). Karnofsky performance status average was 87.6. Fifty-eight (56.3%) patients had single brain metastasis. The average tumor volume was 2.5cc (range 0.02-16.6 cc). The SRS marginal dose average was 23.4 Gy (range 15-25 Gy). Results: Treatment sequence was SRS alone (89 patients) or SRS plus whole-brain radiotherapy (WBRT) (14 patients). The 1-year local control was 80%, being better for tumors with volume <5cc than for >/5 cc: 86% vs 53% (p<0.05). The 1-year distant brain metastasis-free survival incidence was 73%. The initial number of brain lesions (single vs multiple) was not a significant factor on distant brain metastasis: free survival at 1 year was 75% for single metastases and 70% for multiple lesions. Renal cancer was the only factor with a significant effect on distant brain metastasis. The median overall survival was 15 months. According to unifactorial and multifactorial analysis, three prognostic factors for overall survival were retrieved recursive partitioning analysis (RPA) class, Karnofsky index performance and tumor volume. Conclusion: In this series, SRS provided excellent local control with relatively low morbidity in patients with brain metastases.

Objetivo: Avaliar o seguimento clínico e imaginológico de pacientes tratados com radiocirurgia estereotáxica (RC) utilizando Gamma Knife para metástases cerebrais. Casuística e método: Cento e três pacientes com 158 metástases intracranianas tratados com Gamma Knife entre janeiro de 2004 e dezembro de 2006. Os resultados foram baseados no último exame de imagem e na visita mais recente. A média de idade foi 56 anos (32 a 84 anos). O índice de Karnofsky médio foi 87,6. Cinquenta e oito (56,3%) pacientes tiveram metástases cerebrais únicas. A média de volume do tumor foi 2,5cc (0,02-16,6cc). A dose marginal média foi 23.4Gy (15-25Gy). Resultados: Em 89 pacientes foi realizado apenas RC isolada e em 14 pacientes, RC e radioterapia craniana total (RCT). A taxa de controle local em um ano foi 80%, sendo melhor para tumores de volume <5cc do que quando >/ 5 cc: 86% versus 53% (< 0,05). A sobrevida de um ano livre de metástase cerebral distante foi observada em 73%. O número inicial de lesões cerebrais (única versus múltipla) não foi fator significativo para o desenvolvimento de metástases a distância: a sobrevida livre em um ano foi 75% para metástases únicas e 70% para lesões múltiplas. O câncer renal foi o único fator de efeito significativo para o desenvolvimento de metástases cerebrais a distância. A sobrevida global em um ano foi 70%. De acordo com a análise unifatorial e multifatorial, três fatores prognósticos foram encontrados: classe RPA (recursive partitioning analysis), índice de Karnofsky e volume tumoral. Conclusão: Nesta série, a RC proporcionou um excelente controle local com baixa morbidade relativa em pacientes com metástases cerebrais.

Clinical outcomes after Gamma Knife surgery for idiopathic trigeminal neuralgia: review of 76 consecutive cases.

OBJECT: Stereotactic radiosurgery is an increasingly used, and the least invasive, surgical option for patients with trigeminal neuralgia (TN). In this study, the authors performed a retrospective evaluation of the safety and efficacy of this method for idiopathic TN. METHODS: The authors reviewed data from 76 patients with idiopathic TN who underwent Gamma Knife surgery (GKS). The mean age of the patients was 64 years (range 27-83 years). All patients had typical features of TN. Thirty patients (39.5%) had previously undergone surgery. The intervention consisted of GKS on the retrogasserian cisternal portion of the fifth cranial nerve. The mean maximum GKS dose used was 85.1 Gy (range 75-90 Gy). RESULTS: Patients were followed-up from 6 to 42 months (mean 20.3 months) after GKS. Complete pain relief was achieved in 83.1% of the patients within 1 year, 70.9% within 2 years, and 62.5% within 3 years. Patients who underwent previous surgery demonstrated a lower rate of pain relief (p < 0.05). Twenty patients (26.3%) reported pain recurrence between 6 and 42 months after treatment. New or worsened persistent trigeminal dysfunction developed after GKS in 16 patients (21%); 8 of these patients described some facial numbness/not bothersome, and 8 reported some facial numbness/somewhat bothersome. None of the patients developed troublesome dysesthesia or anesthesia dolorosa. CONCLUSIONS: Gamma Knife surgery for idiopathic TN proved to be safe and effective and was associated with a particularly low rate of complications.