| Question 1: According to the Poisson model, the tumor control probability TCP=e-[S] where [S] is |
| Reference: | Bentzen S. “Dose-response relationships in radiotherapy” in “Basic Clinical Radiobiology” edited by Joiner M. and van der Kogel A. |
| Choice A: | The initial number of clonogenic cells in the tumor |
| Choice B: | The total dose administered to the tumor |
| Choice C: | The average number of surviving clonogens after the radiation treatment |
| Choice D: | The number of days after the treatment |
| Choice E: | The probability of zero survival clonogenic cells |
| Question 2: In the LQ model formula for the surviving fraction S=exp?(-aD-ßGD^2 ), the Lea-Catheside factor G |
| Reference: | Sachs R.K., Hahnfeld P. and Brenner D. J. “The link between low LET dose-response relations and the underlying kinetics of damage production/repair/misrepair” Int. J. Radiat. Biol. 72(351-374) 1997. |
| Choice A: | is always equal or larger than 1 |
| Choice B: | is always equal or smaller than 1 |
| Choice C: | Not used for fractionated radiotherapy |
| Choice D: | Accounts for sub-lethal damage repair during or between radiation fractions |
| Choice E: | B and D |
| Question 3: The a/ß ratio in the LQ model |
| Reference: | “Radiobiology for the Radiologist”. E. Hall |
| Choice A: | accounts for the sensitivity of the cells to fractionation changes |
| Choice B: | has units of dose |
| Choice C: | is the dose at which the linear and quadratic terms in the LQ model are equal |
| Choice D: | is always higher for normal tissues than for tumors |
| Choice E: | A, B and C |
| Question 4: If organ and response are described as parallel (n˜1), equivalent uniform dose (EUD) for a highly non-uniform dose distribution is close to: |
| Reference: | Wu Q et al. “Optimization of Intensity-Modulated Radiotherapy Plans Based on the Equivalent Uniform Dose”, IJROBP, 2002, 52:224-235 |
| Choice A: | Maximum dose |
| Choice B: | Mean dose |
| Choice C: | Prescribed dose |
| Choice D: | Minimum dose to the hottest 0.035 cc |
| Choice E: | 95% of prescribed dose |
| Question 5: Identifying structures in an OAR, for example, white matter tract structures in the brain, will allow us to: |
| Reference: | Fried DV et al. “Imaging Radiation-Induced Normal Tissue Injury to Quantify Regional Dose Response”, Seminars Radiat Oncol, 2017, 27:325-331 |
| Choice A: | Connect toxicity, for example, a decline in cognitive function, to a particular structure |
| Choice B: | Develop sophisticated planning goals to selectively avoid specific structures rather than optimizing on an organ as a whole |
| Choice C: | Build sophisticated NTCP models accounting for dose to structures rather than organ as a whole |
| Choice D: | Propose clinical trials to test if selective sparing of structures rather than organ as a whole leads to improved outcomes |
| Choice E: | A, B, C and D |
| Question 6: Function-weighted mean dose for an organ at risk (OAR) allows us to: |
| Reference: | Seppenwoolde Y et al. “Optimizing radiation treatment plans for lung cancer using lung perfusion information”, Radiother Oncol, 2002, 63: 165-177 |
| Choice A: | Account for functionality and importance of a particular OAR relative to other OARs |
| Choice B: | Eliminate dose from predicting NTCP |
| Choice C: | Identify location of stem cells in normal tissue |
| Choice D: | Account for distribution of function in OAR by weighing dose to voxels by fractional function |
| Choice E: | Delineate functional region of OAR that has to be preferentially spared |
