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The role of prophylactic radiotherapy in prevention of brain metastasis

Despite of these side effects, many studies concluded that the benefits of prophylactic brain radiation in prevention and delaying the spread of cancer overcome its harmful effects. This review aimed to evaluate the literature assessing the role of prophylactic radiotherapy in prevention of metastasis to the brain tissues, measure its incidence and the overall survival rates in patient with lung cancer to provide evidence-based data 
Methods: 
Electronic search was performed in Medline using Pubmed resulted in 107 eligible studies. The titles and abstracts of all these articles, was screened and based on this reading studies excluded due to irrelevancy or duplication. 
Results: 
Search of the literature identified total of 107 studies, after exclusion of irrelevant, duplicated and review studies, five studies were included in the review as they met the inclusion criteria. The included studies pointed to assess the effect of prophylactic radiotherapy in avoidance of brain metastasis. All included studies were randomized controlled trials. Total numbers of 1399 patients were recruited in the included studies. Age of patients range from 39 up to 84 years old or more.  Small-cell lung cancer was the primary cancer in three of the included studies. One of the included studies assessed patients with non-small cell lung cancer and one study included patients with small cell anaplastic bronchogenic carcinoma. 
Conclusions: 
The use of prophylactic radiotherapy is effective in reduction of incidence of brain metastasis, but it had no role in rising of the overall survival.