title: Potential of using cerium oxide nanoparticles for protecting healthy tissue during accelerated partial breast irradiation (APBI).
abstract: The purpose of this study is to investigate the feasibility of using cerium oxide nanoparticles (CONPs) as radical scavengers during accelerated partial breast irradiation (APBI) to protect normal tissue. We hypothesize that CONPs can be slowly released from the routinely used APBI balloon applicators-via a degradable coating-and protect the normal tissue on the border of the lumpectomy cavity over the duration of APBI. To assess the feasibility of this approach, we analytically calculated the initial concentration of CONPs required to protect normal breast tissue from reactive oxygen species (ROS) and the time required for the particles to diffuse to various distances from the lumpectomy wall. Given that cerium has a high atomic number, we took into account the possible inadvertent dose enhancement that could occur due to the photoelectric interactions with radiotherapy photons. To protect against a typical MammoSite treatment fraction of 3.4Gy, 5ng·g(-1) of CONPs is required to scavenge hydroxyl radicals and hydrogen peroxide. Using 2nm sized NPs, with an initial concentration of 1mg·g(-1), we found that 2-10days of diffusion is required to obtain desired concentrations of CONPs in regions 1-2cm away from the lumpectomy wall. The resultant dose enhancement factor (DEF) is less than 1.01 under such conditions. Our results predict that CONPs can be employed for radioprotection during APBI using a new design in which balloon applicators are coated with the NPs for sustained/controlled in-situ release from within the lumpectomy cavity.
authors.affiliation: University of Massachusetts Lowell, Lowell, MA, USA. Electronic address: Zi_Ouyang@student.uml.edu.
authors.forename: Zi
authors.initials: Z
authors.lastname: Ouyang
authors.affiliation: University of Massachusetts Boston, Boston, MA, USA.
authors.forename: Madan Kumar
authors.initials: MK
authors.lastname: Mainali
authors.affiliation: Wentworth Institute of Technology, Boston, MA, USA.
authors.forename: Neeharika
authors.initials: N
authors.lastname: Sinha
authors.affiliation: University of Massachusetts Lowell, Lowell, MA, USA.
authors.forename: Guinevere
authors.initials: G
authors.lastname: Strack
authors.affiliation: University of Massachusetts Lowell, Lowell, MA, USA.
authors.forename: Yucel
authors.initials: Y
authors.lastname: Altundal
authors.affiliation: University of Massachusetts Lowell, Lowell, MA, USA.
authors.forename: Yao
authors.initials: Y
authors.lastname: Hao
authors.affiliation: Space Coast Cancer Center, Titusville, FL, USA.
authors.forename: Thomas Andrew
authors.initials: TA
authors.lastname: Winningham
authors.affiliation: University of Massachusetts Lowell, Lowell, MA, USA.
authors.forename: Erno
authors.initials: E
authors.lastname: Sajo
authors.affiliation: University of Massachusetts Boston, Boston, MA, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Celli
authors.affiliation: University of Massachusetts Lowell, Lowell, MA, USA; Brigham and Women's Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA.
authors.forename: Wilfred
authors.initials: W
authors.lastname: Ngwa
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism / Q000532:radiotherapy*; D002563:Cerium / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D008954:Models, Biological; D053758:Nanoparticles / Q000008:administration & dosage* / Q000378:metabolism; D011837:Radiation-Protective Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D011880:Radiotherapy Planning, Computer-Assisted; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; D002563:Cerium; C030583:ceric oxide
keywords: APBI; Cerium oxide; Radiolysis; Radioprotectant