Radiation therapy or brachytherapy devices, systems and methods are in general catheter form and include at least one balloon that assists in placement of radio therapeutic members at desired treatment locations within an existing body cavity or at a site that was formed under a patient's skin for treatment purposes. One or more detectors, such as microdiodes, are present on the device, and a hyperthermia tube or the like is also included that delivers hyperthermia treatment for the target treatment site or sites. Data collected by the detector allows the medical professional to monitor radiation treatment and, when desired, interaction between hyperthermia treatment and radiation delivery by the radiation treatment member.