Biodegradable inflatable balloon for reducing radiation adverse effects in prostate cancer

Carcinoma of the prostate is one of the most abundant killers for men in the western world, and it is frequently treated via Radiation therapy. Unfortunately, radiotherapy side effects include rectal irritation and bleeding, erectile dysfunction and urinary frequency. Because radiation intensity decays rapidly as a function of distance, displacing irradiated prostate away from normal tissues would reduce damage and therefore side effects. The objective of this study is to develop an inflatable balloon that is implanted via a minimal invasive procedure. The balloon is made of a biodegradable polymer called poly(lactide-co-ε-caprolactone). The implant is inserted rolled throughout the perineum; inflated in situ with a physiological saline; sealed and placed between the rectum wall, and the prostate gland. Balloon's mechanical and chemical properties were extensively characterized both in vitro and in vivo. The balloon's preparation ensures no bonding across surfaces as these may endanger the implant mechanical stability. Moreover, the coating method does not alter the polymer's molecular weight and therefore preserve its mechanical properties. Balloon's sterilization was carried out using ethylene oxide which, as our results show and in comparison with γ-irradiation, doesn't damage the mechanical stability of the implant. The proper functionality of the insertion-mounting device as well as the balloon capability to retain its inflated form during patients' radiation session was demonstrated both in vitro and in vivo.