Clinical implementations of 4D pencil beam scanned particle therapy: Report on the 4D treatment planning workshop 2016 and 2017

In 2016 and 2017, the 8th and 9th 4D treatment planning workshop took place in Groningen (the Netherlands) and Vienna (Austria), respectively. This annual workshop brings together international experts to discuss research, advances in clinical implementation as well as problems and challenges in 4D treatment planning, mainly in spot scanned proton therapy. In the last two years several aspects like treatment planning, beam delivery, Monte Carlo simulations, motion modeling and monitoring, QA phantoms as well as 4D imaging were thoroughly discussed. This report provides an overview of discussed topics, recent findings and literature review from the last two years. Its main focus is to highlight translation of 4D research into clinical practice and to discuss remaining challenges and pitfalls that still need to be addressed and to be overcome

Improving proton therapy by metal-containing nanoparticles: nanoscale insights

Thomas Schlathölter,1 Pierre Eustache,2 Erika Porcel,2 Daniela Salado,2 Lenka Stefancikova,2 Olivier Tillement,3 Francois Lux,3 Pierre Mowat,3 Aleksandra K Biegun,4 Marc-Jan van Goethem,4 Hynd Remita,5 Sandrine Lacombe2 1Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands; 2Institut des Sciences Moléculaires d’Orsay (ISMO), Univ. Paris Sud, CNRS, Université Paris Saclay, Orsay Cedex, 3Institut Lumière Matière, Villeurbanne Cedex, France; 4Kernfysisch Versneller Instituut – Center for Advanced Radiation Technology (KVI-CART), University of Groningen, Groningen, the Netherlands; 5Laboratoire de Chimie Physique, Universite Paris-Sud, Orsay Cedex, France Abstract: The use of nanoparticles to enhance the effect of radiation-based cancer treatments is a growing field of study and recently, even nanoparticle-induced improvement of proton therapy performance has been investigated. Aiming at a clinical implementation of this approach, it is essential to characterize the mechanisms underlying the synergistic effects of nanoparticles combined with proton irradiation. In this study, we investigated the effect of platinum- and gadolinium-based nanoparticles on the nanoscale damage induced by a proton beam of therapeutically relevant energy (150 MeV) using plasmid DNA molecular probe. Two conditions of irradiation (0.44 and 3.6 keV/µm) were considered to mimic the beam properties at the entrance and at the end of the proton track. We demonstrate that the two metal-containing nanoparticles amplify, in particular, the induction of nanosize damages (>2 nm) which are most lethal for cells. More importantly, this effect is even more pronounced at the end of the proton track. This work gives a new insight into the underlying mechanisms on the nanoscale and indicates that the addition of metal-based nanoparticles is a promising strategy not only to increase the cell killing action of fast protons, but also to improve tumor targeting. Keywords: gadolinium-based nanoparticles, platinum nanoparticles, nanosensitization, theranostic