title: Targeted radiotherapy enhancement during electronic brachytherapy of accelerated partial breast irradiation (APBI) using controlled release of gold nanoparticles.
abstract: Several studies have demonstrated low rates of local recurrence with brachytherapy-based accelerated partial breast irradiation (APBI). However, long-term outcomes on toxicity (e.g. telangiectasia) and cosmesis remain a major concern. The purpose of this study is to investigate the dosimetric feasibility of using targeted non-toxic radiosensitizing gold nanoparticles (GNPs) for localized dose enhancement to the planning target volume (PTV) during electronic brachytherapy APBI while reducing normal tissue toxicity. We propose to incorporate GNPs into a micrometer-thick polymer film on the surface of routinely used lumpectomy balloon applicators and provide subsequent treatment using a 50 kVp Xoft device. An experimentally determined diffusion coefficient was used to determine space-time customizable distribution of GNPs for feasible in-vivo concentrations of 7 mg/g and 43 mg/g. An analytical approach from previously published work was employed to estimate the dose enhancement due to GNPs as a function of distance up to 1 cm from the lumpectomy cavity surface. Clinically significant dose enhancement values of at least 1.2, due to 2 nm GNPs, were found at 1 cm away from the lumpectomy cavity wall when using electronic brachytherapy APBI. Higher customizable dose enhancement was also achieved at other distances as a function of nanoparticle size. Our preliminary results suggest that significant dose enhancement can be achieved to residual tumor cells targeted with GNPs during APBI with electronic brachytherapy.
authors.affiliation: Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts at Lowell, 1 University Ave., Olney Science Center, Lowell, MA 01854, USA; Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, 450 Brookline Ave., Jimmy Fund Building, Boston, MA 02215, USA. Electronic address: gizemcifter@gmail.com.
authors.forename: G
authors.initials: G
authors.lastname: Cifter
authors.affiliation: Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts at Lowell, 1 University Ave., Olney Science Center, Lowell, MA 01854, USA.
authors.forename: J
authors.initials: J
authors.lastname: Chin
authors.affiliation: Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, 450 Brookline Ave., Jimmy Fund Building, Boston, MA 02215, USA.
authors.forename: F
authors.initials: F
authors.lastname: Cifter
authors.affiliation: Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts at Lowell, 1 University Ave., Olney Science Center, Lowell, MA 01854, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Altundal
authors.affiliation: Department of Sciences, Wentworth Institute of Technology, 550 Huntington Ave., Boston, MA 02115, USA.
authors.forename: N
authors.initials: N
authors.lastname: Sinha
authors.affiliation: Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts at Lowell, 1 University Ave., Olney Science Center, Lowell, MA 01854, USA.
authors.forename: E
authors.initials: E
authors.lastname: Sajo
authors.affiliation: Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts at Lowell, 1 University Ave., Olney Science Center, Lowell, MA 01854, USA; Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, 450 Brookline Ave., Jimmy Fund Building, Boston, MA 02215, USA.
authors.forename: W
authors.initials: W
authors.lastname: Ngwa
mesh_terms: D001918:Brachytherapy / Q000295:instrumentation*; D001940:Breast / Q000187:drug effects* / Q000528:radiation effects*; D001943:Breast Neoplasms / Q000532:radiotherapy; D003692:Delayed-Action Preparations; D055615:Electrical Equipment and Supplies; D005240:Feasibility Studies; D006046:Gold / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology*; D006801:Humans; D053768:Metal Nanoparticles; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D011874:Radiometry; D011879:Radiotherapy Dosage
chemical_list: D003692:Delayed-Action Preparations; D011838:Radiation-Sensitizing Agents; D006046:Gold
keywords: 50 kVp; APBI; Dose enhancement; Gold; Nanoparticles; Xoft electronic brachytherapy