***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Survival data of 114 patients treated for malignant brain tumors with 125I interstitial radiation therapy at Henry Ford Hospital , Detroit , Mich. ( 1986 - 1990 ) , are presented . The first 64 patients were treated with temporary 125I implants with a total prescribed dose of 60 Gy at a dose rate of 40 cGy/h . In order to reduce the risk of injury to the surrounding normal tissue associated with high-dose brachytherapy , a new approach was initiated using permanent implants with a lower dose rate ; 50 patients were treated after surgical resection  with permanent implantation of 125I seeds at a lower dose rate of 4 - 7 cGy/h , with a total dose of 10,000 - 12,000 cGy , and concurrent external radiation therapy of 5,000 cGy . The rationale of this protocol was to increase the effectiveness of the low-dose-rate implant by a concurrent ' daily ' boost of external radiation , thus inhibiting the proliferation of tumor cells during the protracted low-dose radiation treatment . Survival was compared between groups with permanent and temporary implants in terms of effectiveness in tumor control as well as impact on clinical condition . Low-dose-rate implant with concurrent external radiation therapy seems to offer the best chance for long-term survival without deterioration in the clinical condition 
    Output:
    
Results Most data focused on 125I and suggested that it offers rates of local control and overall survival comparable to st and ard of care modalities such as SRS .
However , radiation necrosis and regional recurrence were often high with this isotope .
Studies using photon radiosurgery modality of brachytherapy have also been completed , result ing superior regional control as compared to SRS , but worse local control and higher rates of radiation necrosis than 125I .
More recently , studies using the 131Cs for brachytherapy offered similar local control and survival benefits to 125I , with low rates of radiation necrosis .
Conclusions For a variety of reasons including absence of physician expertise in brachytherapy , lack of published data on treatment outcomes , and rates of radiation necrosis , brachytherapy is not presently a part of st and ard paradigm for brain metastases .