Apparatus, systems and methods for delivering brachytherapy to a target tissue region of a human or other mammalian body. In some embodiments, a flexible brachytherapy device is implanted that includes a therapy delivery portion having one or more radioactive sources securely retained thereto, and a tail portion extending from the therapy delivery portion. Once implanted, the tail portion may extend outside the body, where it may be folded and secured flat against the skin. The device may be removed at therapy completion. Other embodiments of the invention are directed to systems and methods for delivering brachytherapy devices to the body.