| Question 1: Which of the following are not the key challenges in epidemiological studies of late effects in radiotherapy patients?
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| Reference: | Gonzalez A B D, Wong J, Kleinerman R, Kim C, Morton L and Bekelman J E 2015 Risk of Second Cancers According to Radiation Therapy Technique and Modality in Prostate Cancer Survivors Radiation Oncology Biology 91 295–302
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| Choice A: | A large number of patients are required to obtain enough statistical power. |
| Choice B: | Dosimetry must be highly individualized for accurate risk analysis. |
| Choice C: | Lack of epidemiological and statistical methods developed for radiotherapy patients. |
| Choice D: | Radiation-related second cancer may take 10 or more years to develop. |
| Question 2: Which of the following is not one of the remaining questions in epidemiological studies in radiotherapy patients? |
| Reference: | Newhauser W D, de González A B, Schulte R and Lee C 2016 A Review of Radiotherapy-Induced Late Effects Research after Advanced Technology Treatments Front. Oncol. 6 E359–11 |
| Choice A: | Impact of advanced radiotherapy modalities on the risk of late effects. |
| Choice B: | Risk of subsequent breast cancer after radiotherapy of Hodgkin’s lymphoma. |
| Choice C: | Long-term health problems of pediatric radiotherapy patients. |
| Choice D: | Applicability of population-based risk models to individual patients. |
| Question 3: Why are computational phantoms necessary for calculating out-of-field organ doses? |
| Reference: | 1. R.M. Howell, S.B. Scarboro, S.F. Kry, D.Z. Yaldo, "Accuracy of out-of-field dose calculations by a commercial treatment planning system," Phys Med Biol 55, 6999-7008 (2010).
2. J.Y. Huang, D.S. Followill, X.A. Wang, S.F. Kry, "Accuracy and sources of error of out-of field dose calculations by a commercial treatment planning system for intensity-modulated radiation therapy treatments," J Appl Clin Med Phys 14, 186-197 (2013).
3. M. Stovall, R. Weathers, C. Kasper, S.A. Smith, L. Travis, E. Ron, R. Kleinerman, "Dose reconstruction for therapeutic and diagnostic radiation exposures: use in epidemiological studies," Radiat Res 166, 141-157 (2006).
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| Choice A: | CT scans generally only include anatomy close to the treatment area. |
| Choice B: | Treatment planning systems are generally not accurate far from the edge of the treatment field, i.e., below the 10% isodose. |
| Choice C: | CT scans are often not available. |
| Choice D: | All of the above. |
| Question 4: What level of dosimetry is commonly used to assess temporal trends in late effects with time? |
| Reference: | L.M. Turcotte, Q. Liu, Y. Yasui, M.A. Arnold, S. Hammond, R.M. Howell, S.A. Smith, R.E. Weathers, T.O. Henderson, T.M. Gibson, W. Leisenring, G.T. Armstrong, L.L. Robison, J.P. Neglia, "Temporal Trends in Treatment and Subsequent Neoplasm Risk Among 5-Year Survivors of Childhood Cancer, 1970-2015," Jama-J Am Med Assoc 317, 814-824 (2017).
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| Choice A: | Organ specific dosimetry based on Monte Carlo simulations. |
| Choice B: | Organ specific dosimetry based on analytical models. |
| Choice C: | Radiation yes or no. |
| Choice D: | Body region dosimetry calculated with analytical models. |
| Question 5: For organ dose estimations in late effects studies, when is uncertainty of as much as 50% sometimes acceptable?
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| Reference: | P.D. Inskip, L.L. Robison, M. Stovall, S.A. Smith, S. Hammond, A.C. Mertens, J.A. Whitton, L. Diller, L. Kenney, S.S. Donaldson, A.T. Meadows, J.P. Neglia, "Radiation Dose and Breast Cancer Risk in the Childhood Cancer Survivor Study," J Clin Oncol 27, 3901-3907 (2009).
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| Choice A: | Patients with the outcome of interest will be grouped together in wide dose bins, e.g., 1-10 Gy, 10 – 20 Gy, 20 – 30 Gy, >30 Gy. |
| Choice B: | This level of uncertainty is never acceptable, uncertainties should be consistent with standard of care for treatment, i.e., <5%. |
| Choice C: | This type of uncertainty is only acceptable for in-field and near-field organs. |
| Choice D: | This level of uncertainty is only acceptable for out-of-field organs. |
| Question 6: Which of the following is true about the computational human phantoms?
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| Reference: | Lee C, Jung J W, Pelletier C, Pyakuryal A, Lamart S, Kim J O and Lee C 2015 Reconstruction of organ dose for external radiotherapy patients in retrospective epidemiologic studies 60 2309–24
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| Choice A: | ICRP reference phantoms have simplified material compositions (only water, lung, bone, and air) |
| Choice B: | ICRP reference phantoms cannot be imported into the commercial treatment planning system. |
| Choice C: | Computational phantoms can be used to augment the missing patient anatomy outside of the treatment volume. |
| Choice D: | D. Computational phantoms are not flexible and only available for the reference size. |
| Question 7: Which of the following is NOT true about the advantages and disadvantages of dose calculation using the commercial treatment planning system (TPS) vs. Monte Carlo radiation transport codes?
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| Reference: | Xu X G, Bednarz B and Paganetti H 2008 A review of dosimetry studies on external-beam radiation treatment with respect to second cancer induction Phys. Med. Biol. 53 R193–241
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| Choice A: | TPS is not very well suited for the out-of-the-field dose estimation. |
| Choice B: | Monte Carlo calculation may take significantly longer time than TPS. |
| Choice C: | If correctly modeled, Monte Carlo can estimate the dose out-of-the-field accurately. |
| Choice D: | Monte Carlo algorithm is not currently available in commercial TPS. |
| Question 8: Which of the following is NOT true about the advantages and disadvantages of dose estimation using the measurement vs. calculation? |
| Reference: | Xu X G, Bednarz B and Paganetti H 2008 A review of dosimetry studies on external-beam radiation treatment with respect to second cancer induction Phys. Med. Biol. 53 R193–241 |
| Choice A: | In-vivo phantom measurement requires patient-like physical phantoms and small detectors for patient-specific dose reconstruction. |
| Choice B: | In-vivo phantom measurement can be affected by setup errors. |
| Choice C: | Calculation based approach is always more accurate than the measurement. |
| Choice D: | Calculation based approach can be free from various measurement uncertainties (such as setup errors). |
| Question 9: The sources of stray radiation from linac-based photon therapy include: |
| Reference: | Jagetic L and Newhauser WD, A simple and fast analytical method to calculate doses to the whole body from external beam, megavoltage x-ray therapy. Phys Med Biol. 60 (2015) 4753–4775.
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| Choice A: | The stopping length target that converts electron kinetic energy to Bremsstrahlung photons. |
| Choice B: | The flattening filter that increases the lateral uniformity of the photon beam. |
| Choice C: | The collimators and jaws that limit the beam laterally. |
| Choice D: | The patient receiving the photon beam treatment. |
| Choice E: | The shielding barriers of the treatment vault. |
| Choice F: | All of the above. |
| Question 10: Which of the following are needed calculateradiation exposure in a patient who received proton therapy?
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| Reference: | Newhauser WD, Berrington de Gonzalez A, Schulte R, and Lee C. A Review of Radiotherapy-Induced Late Effects Research After Advanced-Technology Treatments. (Invited review), Frontiers in Oncology. Vol 6, article 13 (2016).
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| Choice A: | Knowledge of the major sources of proton and neutron radiation. |
| Choice B: | Knowledge of the anatomy of the patient’s whole body. |
| Choice C: | Knowledge of treatment factors, such as the proton beam energy and field size. |
| Choice D: | A commercial clinical treatment planning system. |
| Choice E: | A, B and C. |
