ABSTRACT
Summary Objective: To provide a quantitative profile of the indications and use of stereotactic body radiotherapy (SBRT) in a developing country oncology-based institution. In addition, to describe the patients' and treatment characteristics, and to provide a temporal analysis. Method: SBRT patients treated from 2007 to 2015 were retrospectively evaluated by two independently investigators. Data were stratified and compared in two periods: first experience (FE) (May 2007 to April 2011), and following experience (FollowE) (May 2011 to April 2015). The following parameters were compared between the groups: total number of treated patients and lesions, treatment site, additional image fusion used, formal protocol adoption, and SBRT planning technique. Results: One hundred and seventy-six (176) patients with 191 lesions were treated: 34 (18%) lesions in the FE and 157 (82%) lesions in FollowE. The majority of lesions were metastases (60.3%), and lung (60.2%) was the most common treatment site, followed by spine (31%), and others (8.8%). An average of 1.4 (±0.6) additional imaging exams for delineation was performed. Conformal 3D radiotherapy planning technique was used in 64.4%, and intensity modulated radiotherapy (IMRT) or volumetric-modulated arc therapy (VMAT) in the remaining 35.6% (p=0.0001). Higher rates of curative treatments were observed in FE, as well as more lung lesions, patients ≥ 70 years, 3D conformal, number of additional images and ECOG 0, and all presented p<0.05. The global rate of protocol statement was 79%, lung treatment being the most stated. Conclusion: SBRT application is rapidly increasing in our setting. Treatment sites and planning techniques are becoming more diversified and complex.
Resumo Objetivo: realizar uma análise quantitativa das indicações e do uso de SBRT (stereotactic body radiotherapy) em uma instituição filantrópica. Além disso, descrever temporalmente as características dos pacientes e tratamentos. Método: retrospectivamente, foram coletados, por dois investigadores independentes, os dados de todos os pacientes tratados com SBRT na instituição no período de maio de 2007 a fevereiro de 2015. Dados foram estratificados e comparados em dois períodos: inicial (P1) (maio de 2007 a abril de 2011) e período seguinte (P2) (maio de 2011 a abril de 2015). Os seguintes parâmetros foram comparados entre os grupos: número total de pacientes e lesões tratadas, local de tratamento, uso de imagens adicionais, adoção formal de protocolo e técnica de planejamento. Resultados: foram avaliados 176 pacientes e 191 lesões, sendo 34 (18%) no P1 e 157 (82%) no P2, tratados com SBRT. A maioria das lesões eram metastáticas (60,3%), sendo pulmão o sítio mais prevalente, contabilizando 115/191 (60,2%) lesões, seguida de lesões ósseas (30,8%). Uma média de 1,4 (±0,6) exame de imagem adicional foi usada para o delineamento. Uso formal de protocolo/recomendações foi descrito em 79% das lesões. A técnica 3D-conformada (3DCRT - three-dimensional conformal radiotherapy) foi a mais utilizada para planejamento [123/191 (64,4%) lesões] quando comparada à intensidade modulada e ao arco dinâmico (p=0.0001). O P1 esteve associado a maior número de lesões primárias tratadas (OR 2,09; p=0,0005), lesões pulmonares (OR 3,85; p=0,0198), pacientes ≥ 70 anos (OR 2,77; p=0,0005), uso de planejamento 3D (OR 16; p=0,0001), menor uso de imagens adicionais [0 ou 1 (versus > 1)] (OR 7,5; p=0,0001) e ECOG 0 (vs. > 0) (OR 0,21; p=0,0431). Conclusão: o uso de SBRT aumentou ao longo do tempo na instituição. No P2, notou-se uma evolução técnica, com indicações mais diferenciadas, maior uso de imagens auxiliares para definição do alvo e técnicas de planejamento mais sofisticadas.
Subject(s)
Humans , Male , Female , Aged , Radiotherapy Planning, Computer-Assisted/statistics & numerical data , Radiosurgery/statistics & numerical data , Radiotherapy, Conformal/statistics & numerical data , Neoplasms/radiotherapy , Radiotherapy Dosage , Spinal Neoplasms/radiotherapy , Time Factors , Brazil , Survival Analysis , Retrospective Studies , Radiosurgery/methods , Radiosurgery/trends , Developing Countries , Radiotherapy, Intensity-Modulated , Liver Neoplasms/radiotherapy , Lung Neoplasms/radiotherapy , Lung Neoplasms/secondary , Neoplasm Metastasis/radiotherapyABSTRACT
Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and nonrandomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future.