Benefits and drawbacks of specific approaches:
High dose rate prostate brachytherapy
(HDR brachytherapy)
High dose rate brachytherapy entails the placement of hollow tubes into the prostate, through the skin behind the scrotum, through which a high intensity radiation source is delivered and precisely moved through up to several hundred computer controlled “dwell positions,” allowing very precise radiation dose sculpting in and around the prostate. Due to the precision of the radiation dosimetry allowed by this method, a short course of radiotherapy, using large doses per treatment, may be effectively delivered (9).
This approach is known as hypofractionated radiotherapy, and appears well suited to treat prostate malignancy, which appears particularly radiobiologically sensitive to hypofractionation (21). In a prospective comparitive study, HDR brachytherapy provided a 98% 3-year PSA disease-free survival rate, comparable to that seen with Palladium-103 permanent source prostate brachytherapy in the same series, but with significantly decreased urinary tract and sexual symptoms (9).
The major drawback of HDR brachytherapy includes the necessity of a hospital admission for HDR tube placement and maintenance, which increases the expense significantly. Pain control is also challenging, due to the obvious discomfort created by the indwelling tubes themselves. Finally, the tubes may move over time, potentially degrading the accuracy of the radiation delivery by this method (22)
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