Development and international multicentre pilot testing of a postal dosimetry audit methodology for high dose rate brachytherapy.

Background And Purpose: Dosimetry audits are essential for reducing errors in brachytherapy. A postal dosimetry audit methodology was developed and tested in an international multicentre pilot, to assess the accuracy of the Reference Air Kerma Rate of Ir and Co brachytherapy sources.

Materials And Methods: A compact phantom made of polymethyl methacrylate was developed to accommodate two catheters, a radiophotoluminescence dosimeter (RPLD) for dose measurements and a Gafchromic (RTQA2) film strip for source position verification.

Accounting for radiation-induced indirect damage on DNA with the Geant 4-DNA code.

The use of Monte Carlo (MC) simulations remains a powerful tool to study the biological effects induced by ionizing radiation on living beings. Several MC codes are commonly used in research fields such as nanodosimetry, radiotherapy, radiation protection, and space radiation. This work presents an enhancement of an existing model [1] for radiobiological purposes, to account for the indirect DNA damage induced by ionizing particles.

Targeted alpha therapy with Pb or Ac: Change in RBE from daughter migration.

Targeted α-therapy (TAT) could be delivered early to patients who are at a high-risk for developing brain metastases, targeting the areas of the vasculature where tumor cells are penetrating into the brain. We have utilized a Monte Carlo model representing brain vasculature to calculate physical dose and DNA damage from the α-emitters Ac and Pb. The micron-scale dose distributions from all radioactive decay products were modeled in Geant4, including the eV-scale interactions using the Geant4-DNA models.

Dosimetric evaluation of radionuclides for VCAM-1-targeted radionuclide therapy of early brain metastases.

Unlabelled: Brain metastases develop frequently in patients with breast cancer, and present a pressing therapeutic challenge. Expression of vascular cell adhesion molecule 1 (VCAM-1) is upregulated on brain endothelial cells during the early stages of metastasis and provides a target for the detection and treatment of early brain metastases. The aim of this study was to use a model of early brain metastasis to evaluate the efficacy of α-emitting radionuclides, Tb, At, Pb, Bi and Ac; β-emitting radionuclides, Y, Tb and Lu; and Auger electron (AE)-emitters Ga, Zr, In and I, for targeted radionuclide therapy (TRT).