| Question 1: Which of the following most correctly reflects our understanding of clinical RBE in proton and carbon ion therapy? |
| Reference: | Stewart RD, Carlson DJ, Butkus MP, Hawkins R, Friedrich T, Scholz M. A comparison of mechanism-inspired models for particle relative biological effectiveness (RBE). Med Phys. 2018 Nov;45(11):e925-e952. doi: 10.1002/mp.13207. PMID: 30421808
Paganetti H, Blakely E, Carabe-Fernandez A, Carlson DJ, Das IJ, Dong L, Grosshans D, Held KD, Mohan R, Moiseenko V, Niemierko A, Stewart RD, Willers H. Report of the AAPM TG-256 on the relative biological effectiveness of proton beams in radiation therapy. Med Phys. 2019 Mar;46(3):e53-e78. doi: 10.1002/mp.13390. Epub 2019 Feb 14. PMID: 30661238 |
| Choice A: | A constant RBE of 1.1 and 3 is optimal in proton and carbon ion therapy, respectively |
| Choice B: | A three-fold increase in particle LET corresponds to a three-fold increase in the RBE for cell survival |
| Choice C: | Tumor control and organ-at-risk (OAR) damage is unrelated to cell survival |
| Choice D: | RBE is a complex function of biological endpoint, particle type, energy, physics dose, and tissue radiosensitivity |
| Question 2: Linear energy transfer (LET) is |
| Reference: | ICRU. (2011). Report 85: Fundamental Quantities and Units for Ionizing Radiation. Journal of the International Commission on Radiation Units and Measurements, 11(1) |
| Choice A: | The linear relationship between energy transferred by a charged particle and cell kill |
| Choice B: | The mean energy lost by charged particles per unit length |
| Choice C: | The energy lost in a single interaction by a charged particle |
| Choice D: | The median energy transferred along a charged particle track |
| Question 3: Which ion types are considered for RBE predictions in carbon ion radiation therapy? |
| Reference: | Kamp F, Cabal G, Mairani A, Parodi K, Wilkens JJ, Carlson DJ. Fast Biological Modeling for Voxel-based Heavy Ion Treatment Planning Using the Mechanistic Repair-Misrepair-Fixation Model and Nuclear Fragment Spectra. Int J Radiat Oncol Biol Phys. 2015 Nov 1;93(3):557-68. doi: 10.1016/j.ijrobp.2015.07.2264. Epub 2015 Jul 20. PMID: 26460998 |
| Choice A: | Only Carbon ions |
| Choice B: | Carbon ions and protons |
| Choice C: | Carbon ions, protons, helium ions, lithium ions, beryllium ions and boron ions |
| Choice D: | Electrons, photons, neutrons, carbon ions, protons, helium ions, lithium ions, beryllium ions and boron ions |
| Question 4: Clinical data from proton therapy patients |
| Reference: | Wang CC, McNamara AL, Shin J, Schuemann J, Grassberger C, Taghian AG, Jimenez RB, MacDonald SM, Paganetti H. End-of-Range Radiobiological Effect on Rib Fractures in Patients Receiving Proton Therapy for Breast Cancer. Int J Radiat Oncol Biol Phys. 2020 Mar 30:S0360-3016(20)30935-4. doi: 10.1016/j.ijrobp.2020.03.012. Online ahead of print. PMID: 32240774 |
| Choice A: | do show a clear increase of RBE as LET increases |
| Choice B: | do not show any RBE variations |
| Choice C: | do show an increasing RBE at the end of range in some clinical data |
| Choice D: | do show that the current RBE of 1.1 is underestimated |
| Question 5: LET optimization of particle therapy |
| Reference: | Unkelbach J, Botas P, Giantsoudi D, Gorissen BL, Paganetti H. Reoptimization of Intensity Modulated Proton Therapy Plans Based on Linear Energy Transfer. Int J Radiat Oncol Biol Phys. 2016 Dec 1;96(5):1097-1106. doi: 10.1016/j.ijrobp.2016.08.038. Epub 2016 Sep 1. PMID: 27869082 |
| Choice A: | does make RBE based optimization obsolete |
| Choice B: | allows decreasing the LET in organs at risk |
| Choice C: | mainly allows increasing the LET in the tumor |
| Choice D: | requires Monte Carlo based treatment planning |
| Question 6: Which of the following statement is most correct regarding particle RBE |
| Reference: | Stewart RD, Carlson DJ, Butkus MP, Hawkins R, Friedrich T, Scholz M. A comparison of mechanism-inspired models for particle relative biological effectiveness (RBE). Med Phys. 2018 Nov;45(11):e925-e952. doi: 10.1002/mp.13207. PMID: 30421808
Kamp F, Cabal G, Mairani A, Parodi K, Wilkens JJ, Carlson DJ. Fast Biological Modeling for Voxel-based Heavy Ion Treatment Planning Using the Mechanistic Repair-Misrepair-Fixation Model and Nuclear Fragment Spectra. Int J Radiat Oncol Biol Phys. 2015 Nov 1;93(3):557-68. doi: 10.1016/j.ijrobp.2015.07.2264. Epub 2015 Jul 20. PMID: 26460998 |
| Choice A: | the RBE for DNA double strand break induction (RBEDSB) is greater than the RBE for cell survival |
| Choice B: | the RBE for cell survival has no predictive value for clinical endpoints |
| Choice C: | the RBE for cell survival is a linear function of proton and carbon ion LET |
| Choice D: | plans with multiple ions and energy (or LET) distributions need to consider the appropriate dosimetric LET or RBE weighting as it relates to clinical endpoints of interest |
