2017 AAPM Annual Meeting
Back to session list

Session Title: 90Y-Microsphere Therapy: Emerging Trends and Future Directions
Question 1: According to the NRC, what are the release criteria for patients receiving Y-90 microsphere therapy?
Reference:Release of Patients Administered Radioactive Materials. Regulatory guide 8.39. NRC; April 1997. Available at https://www.nrc.gov/docs/ML0833/ML083300045.pdf
Choice A:Patients can be released provided they agree to minimize contact with other individuals for 3 days (~1 half-life) post-treatment.
Choice B:Patients must be provided with written instructions regarding exposure to other individuals.
Choice C:Patients may be released provided the measured dose rate at 1 meter is less than 0.07 mSv/h.
Choice D:There are no release criteria for patients receiving Y-90 microsphere therapy.
Question 2: In a Y-90 microsphere therapy treatment plan, an average lobe dose of 90 Gy is prescribed to the right lobe (1500 mL). Most of the right lobe consists of normal tissue except for a small 15 mL tumor. The pre-treatment Tc-99m MAA study reveals a tumor/normal tissue uptake ratio of 3. The dose to the tumor will be around:
Reference:Dezarn, William A., et al. "Recommendations of the American Association of Physicists in Medicine on dosimetry, imaging, and quality assurance procedures for Y-90 microsphere brachytherapy in the treatment of hepatic malignancies." Medical Physics 38.8 (2011): 4824-4845.
Choice A:30 Gy.
Choice B:90 Gy.
Choice C:180 Gy.
Choice D:270 Gy.
Question 3: The physical properties of Yttrium-90 that makes it well suited for internal radionuclide therapy are that Y-90 is a pure b- emitter with a maximum energy of 2.28 MeV corresponding to a maximum tissue penetration depth of:
Reference:Sarfaraz M, Kennedy AS, Lodge MA, Li XA, Wu X, Yu CX, “Radiation absorbed dose distribution in a patient treated with yttrium-90 microspheres for hepatocellular carcinoma,” Medical Physics 31(9):2449-53, 2004
Choice A:~0.1 mm
Choice B:~1 mm
Choice C:~10 mm
Choice D:~100 mm
Question 4: The dosimetry model capable of providing the spatial distribution of absorbed doses within tumors and normal liver volumes is:
Reference:Smits MLJ, et al., “Radioembolization dosimetry: The road ahead,” Cardiovasc Intevent Radiol 38:261-269, 2015; D’Arienzo M, et al., “Y-90 PET based dosimetry after SIRT,” Nuc Med Comm 33:633-640, 2012
Choice A:Body Surface Area (BSA) Model.
Choice B:MIRD Model.
Choice C:Partition Model.
Choice D:Voxel Dosimetry Model.
Question 5: Several techniques (in addition to coil embolization) have been used to decrease the incidence of extrahepatic microsphere deposition. Other than avoiding the GDA, standard recommendations suggest that SPECT/CT of intra-arterial administered [Tc99m] MAA (or HSA) be used to determine extrahepatic deposition of microspheres. What imaging technique is strongly recommended and may become the standard of care for determining extrahepatic deposition?
Reference:Siddharth A. Padia, MD, et al. Radioembolization of Hepatic Malignancies: Background, Quality Improvement Guidelines, and Future Directions. J Vasc Interv Radiol 2017; 28:1–15
Choice A:PET/CT with free yttrium-90.
Choice B:MRA.
Choice C:FPCBCT-flat panel cone beam CT.
Choice D:Bremsstrahlung Angiography.
Question 6: The 2016 Modified RECIST for hepatocellular carcinoma discusses the modification to the criteria standard based on evaluating tumour necrosis. To incorporate this criteria, the residual viable tumour must be quantified, and was defined as uptake of what?
Reference:L.H. Schwartz et al. RECIST 1.1 e Standardisation and disease-specific adaptations: Perspectives from the RECIST Working Group. Eur J Cancer 2016; 62:138-145
Choice A:FDG based on PET/CT.
Choice B:contrast agent in the arterial phase of dynamic CT or MRI.
Choice C:contrast agent following delayed FPCBCT.
Choice D:MAA in the tumor using SPECT/CT.
Back to session list