- Email: [email protected]
Resource, Administrator or Clinical Expert? An Examination of Radiation Therapy Unit Supervisor Roles
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Resource, Administrator or Clinical Expert? An Examination of Radiation Therapy Unit Supervisor Roles Amanda Bolderston, RTT, MSc, FCAMRT, Karen Yendley, RTT, BSc, Cheryl McGregor, RTT, ACT, CTIC, Anthony Slowey, RTT, BSc and Sharan Manship, RTT, MBA British Columbia Cancer Agency E-mail: [email protected] Background: Canadian radiation therapy departments usually have flat organizational structures, with relatively few administrative/managerial levels. The ‘‘unit supervisor’’ (US) level is a typical job role that provides direct supervision of one or more treatment units with a mixture of clinical and administrative duties. Methods: At the British Columbia Cancer Agency (BCCA) the US role was recently evaluated using telephone interviews to examine similar roles across Canada (n¼9), qualitative face-to-face interviews with the BCCA unit supervisors (n¼22) and a quantitative electronic survey (n¼140) comparing the views of the US role between clinical radiation therapists and department managers. Results: Data indicated that departmental administrative tasks seem to be increasing significantly and there is a move towards the addition of more administrative ‘‘middle’’ roles across the country to deal with these. US roles are subsequently becoming less clinical but there is an emerging tension with moving away from solely clinical responsibilities and assuming more administrative work. As time elapses, hands on clinical skills are often eroded but this expertise continues to be an expectation of the US role. The most prevalent interview theme was ‘‘clinical practice,’’ the ability or inability to be truly a clinical expert/resource with the administrative expectations, and other stakeholder’s expectations regarding it. This tied in to the ‘‘jack of all trades’’ theme that spoke to the difficulty of being a generalist in the current technological environment. However despite this trend, 65% of radiation therapist survey respondents felt strongly that the roles should be more clinical and less administrative. Role clarity (internal and external) was another preoccupation borne out by both the interviews and survey. For example, only 46% of the radiation therapists surveyed felt they had a good idea of what the US role entailed. Conclusions: The historical US role was part of the team and did little administrative work. This model is becoming difficult to sustain, and tensions can arise in this new environment when still using old organizational models. Role expectations need to be examined, clarified and communicated within departments. If US roles are deemed clinical experts, then clinical time needs to be protected for expertise to be sustained. ORAL ABSTRACTS PERSONALIZED RADIOTHERAPY
Impact of Image Registration Surrogates on PTV Geometry for Bladder Radiotherapy Vickie Kong, MTS, MRT(T) Princess Margaret Cancer Center E-mail: [email protected] Tara Rosewall, MSc, MRT(T) Princess Margaret Cancer Center, University of Toronto Joanne Moseley, BSc Princess Margaret Cancer Center Tim Craig, PhD, Michael Milosevic, MD, Robert Bristow, MD and Peter Chung, MD Princess Margaret Cancer Center, University of Toronto Purpose: Lipiodol is a radiopaque marker that has been used as the image registration surrogate for partial bladder radiotherapy to generate patient-specific PTV (PS-PTV) in order to facilitate dose reduction to normal tissue. However, injecting Lipiodol to demarcate the target volume is an invasive procedure.
Center of Bladder (COB) and Bladder Wall Surface encompassed by the CTV (BWS) are proposed to be the alternative non-invasive surrogates. This study examines the impact of using these three surrogates for image registration on the resultant geometry of PS-PTV. Materials/Methods: Twenty bladder cancer patients who had Lipiodol injection prior to planning CT were included. Lipiodol, CTV and bladder were delineated on the planning CT. In addition, CTVs were delineated on 5 CBCTs from each patient. CBCTs were registered to planning CT using three different surrogates: Lipiodol, COB and BWS. Occupancy volume was generated by combining all 5 CTVs after each registration method, and a 3mm expansion was then applied to create the Lipiodol-PTV, COB-PTV and BWS-PTV. Using the LipiodolPTV as the reference, discrepancies between the PTVs were quantified using volumes, Dice Similarity Coefficient (DSC) and Distance between Surfaces. Results: A total of 60 volumes were generated for analysis. BWS-PTV has a more comparable volume and shape to Lipiodol-PTV (mean ratio and DSC: 1.01 and 0.87) than COB-PTV (mean ratio and DSC: 1.11 and 0.79). There were 5 COB-PTVs (25%) and 10 BWS-PTV (50%) in which the volumes were smaller than Lipiodol-PTV. Mean distance between surfaces (mm) were 1.1, 1.0 and 1.1 for BWS-PTV and 1.5, 1.4 and 1.7 for COB-PTV in the left-right, anterior-posterior and superior-inferior direction, respectively. Mean percentage frequency of distance between surfaces >3mm and >5mm was significantly lower for BWS-PTV than COB-PTV (>3mm: 41% vs 58% and >5mm: 21% vs 39%, p < 0.03). Conclusion: Larger variation both in volume and shape from the LipiodolPTV was observed when COB was used for image registration. BWS is the preferred non-invasive surrogate for partial bladder radiotherapy. Further investigation on the interobserver variability of these image registration surrogates is needed to identify the optimal method. Gold Nanoparticles for Radiation Therapy Charmainne Cruje Ryerson University and Peel Regional Cancer Centre E-mail: [email protected] Devika B. Chithrani, PhD Ryerson University Li Ka Shing Knowledge Institute Background: The use of inorganic nanoparticles (NPs) for improved cancer therapeutics has been studied extensively. However, further optimizations of NP-based treatments have yet to be done to achieve clinical implementation. These include minimizing damage to healthy organs such as the kidney, spleen and liver. The key to minimizing side effects is NP-targeting to cancer cells for maximized chemotherapy or radiation results. It must be noted that before NPs can enter cancer cells, entry into tumour interstitial tissue must be accomplished first. This work investigates the entry of such targeting gold NPs (GNPs) in cervical and breast cancer cells (HeLa and MDA-MB-231) in vitro. Radiation therapeutic enhancement was observed using an orthovoltage photon energy and will be observed for a megavoltage photon energy. Summary: Spherical GNPs were synthesized and characterized to be 14, 50 and 70 nm in diameter. GNPs were either coated with polyethylene glycol (PEG) alone or in addition to a targeting peptide. GNPs were incubated with HeLa and MDA-MB-231 cells. This was followed by quantification of GNPs in cells and microscopy. PEG, which increases tumour interstitial tissue targeting but decreases cancer cell entry, was found to reduce cell entry when used to coat GNPs alone. GNPs coated with peptides and PEG had improved cell entry for all GNP sizes in HeLa cells and for 14 nm GNPs in MDA-MB-231 cells. Preliminary results show therapeutic enhancement with 50 nm NPs in an orthvoltage photon energy of 220 kVp for HeLa cells. Prospective therapeutic improvement with the same NPs will be studied using the more commonly used megavoltage photon energy of 6 MVp. Conclusion: Since cell targeting peptides improve NP entry into cells, there are improved radiation results for an orthvoltage photon energy. The same is expected for a megavoltage photon energy. Results from this study may be used to design NPs with longer blood circulation times and improved cancer cell entry. Such an optimized design will advance the clinical use of NP-based platforms in radiation therapy.
Conference Proceedings from RTi3 2015/Journal of Medical Imaging and Radiation Sciences 46/S1 (2015) S2-S30
S3
Resource, Administrator or Clinical Expert? An Examination of Radiation Therapy Unit Supervisor Roles Amanda Bolderston, RTT, MSc, FCAMRT, Karen Yendley, RTT, BSc, Cheryl McGregor, RTT, ACT, CTIC, Anthony Slowey, RTT, BSc and Sharan Manship, RTT, MBA British Columbia Cancer Agency E-mail: [email protected] Background: Canadian radiation therapy departments usually have flat organizational structures, with relatively few administrative/managerial levels. The ‘‘unit supervisor’’ (US) level is a typical job role that provides direct supervision of one or more treatment units with a mixture of clinical and administrative duties. Methods: At the British Columbia Cancer Agency (BCCA) the US role was recently evaluated using telephone interviews to examine similar roles across Canada (n¼9), qualitative face-to-face interviews with the BCCA unit supervisors (n¼22) and a quantitative electronic survey (n¼140) comparing the views of the US role between clinical radiation therapists and department managers. Results: Data indicated that departmental administrative tasks seem to be increasing significantly and there is a move towards the addition of more administrative ‘‘middle’’ roles across the country to deal with these. US roles are subsequently becoming less clinical but there is an emerging tension with moving away from solely clinical responsibilities and assuming more administrative work. As time elapses, hands on clinical skills are often eroded but this expertise continues to be an expectation of the US role. The most prevalent interview theme was ‘‘clinical practice,’’ the ability or inability to be truly a clinical expert/resource with the administrative expectations, and other stakeholder’s expectations regarding it. This tied in to the ‘‘jack of all trades’’ theme that spoke to the difficulty of being a generalist in the current technological environment. However despite this trend, 65% of radiation therapist survey respondents felt strongly that the roles should be more clinical and less administrative. Role clarity (internal and external) was another preoccupation borne out by both the interviews and survey. For example, only 46% of the radiation therapists surveyed felt they had a good idea of what the US role entailed. Conclusions: The historical US role was part of the team and did little administrative work. This model is becoming difficult to sustain, and tensions can arise in this new environment when still using old organizational models. Role expectations need to be examined, clarified and communicated within departments. If US roles are deemed clinical experts, then clinical time needs to be protected for expertise to be sustained. ORAL ABSTRACTS PERSONALIZED RADIOTHERAPY
Impact of Image Registration Surrogates on PTV Geometry for Bladder Radiotherapy Vickie Kong, MTS, MRT(T) Princess Margaret Cancer Center E-mail: [email protected] Tara Rosewall, MSc, MRT(T) Princess Margaret Cancer Center, University of Toronto Joanne Moseley, BSc Princess Margaret Cancer Center Tim Craig, PhD, Michael Milosevic, MD, Robert Bristow, MD and Peter Chung, MD Princess Margaret Cancer Center, University of Toronto Purpose: Lipiodol is a radiopaque marker that has been used as the image registration surrogate for partial bladder radiotherapy to generate patient-specific PTV (PS-PTV) in order to facilitate dose reduction to normal tissue. However, injecting Lipiodol to demarcate the target volume is an invasive procedure.
Center of Bladder (COB) and Bladder Wall Surface encompassed by the CTV (BWS) are proposed to be the alternative non-invasive surrogates. This study examines the impact of using these three surrogates for image registration on the resultant geometry of PS-PTV. Materials/Methods: Twenty bladder cancer patients who had Lipiodol injection prior to planning CT were included. Lipiodol, CTV and bladder were delineated on the planning CT. In addition, CTVs were delineated on 5 CBCTs from each patient. CBCTs were registered to planning CT using three different surrogates: Lipiodol, COB and BWS. Occupancy volume was generated by combining all 5 CTVs after each registration method, and a 3mm expansion was then applied to create the Lipiodol-PTV, COB-PTV and BWS-PTV. Using the LipiodolPTV as the reference, discrepancies between the PTVs were quantified using volumes, Dice Similarity Coefficient (DSC) and Distance between Surfaces. Results: A total of 60 volumes were generated for analysis. BWS-PTV has a more comparable volume and shape to Lipiodol-PTV (mean ratio and DSC: 1.01 and 0.87) than COB-PTV (mean ratio and DSC: 1.11 and 0.79). There were 5 COB-PTVs (25%) and 10 BWS-PTV (50%) in which the volumes were smaller than Lipiodol-PTV. Mean distance between surfaces (mm) were 1.1, 1.0 and 1.1 for BWS-PTV and 1.5, 1.4 and 1.7 for COB-PTV in the left-right, anterior-posterior and superior-inferior direction, respectively. Mean percentage frequency of distance between surfaces >3mm and >5mm was significantly lower for BWS-PTV than COB-PTV (>3mm: 41% vs 58% and >5mm: 21% vs 39%, p < 0.03). Conclusion: Larger variation both in volume and shape from the LipiodolPTV was observed when COB was used for image registration. BWS is the preferred non-invasive surrogate for partial bladder radiotherapy. Further investigation on the interobserver variability of these image registration surrogates is needed to identify the optimal method. Gold Nanoparticles for Radiation Therapy Charmainne Cruje Ryerson University and Peel Regional Cancer Centre E-mail: [email protected] Devika B. Chithrani, PhD Ryerson University Li Ka Shing Knowledge Institute Background: The use of inorganic nanoparticles (NPs) for improved cancer therapeutics has been studied extensively. However, further optimizations of NP-based treatments have yet to be done to achieve clinical implementation. These include minimizing damage to healthy organs such as the kidney, spleen and liver. The key to minimizing side effects is NP-targeting to cancer cells for maximized chemotherapy or radiation results. It must be noted that before NPs can enter cancer cells, entry into tumour interstitial tissue must be accomplished first. This work investigates the entry of such targeting gold NPs (GNPs) in cervical and breast cancer cells (HeLa and MDA-MB-231) in vitro. Radiation therapeutic enhancement was observed using an orthovoltage photon energy and will be observed for a megavoltage photon energy. Summary: Spherical GNPs were synthesized and characterized to be 14, 50 and 70 nm in diameter. GNPs were either coated with polyethylene glycol (PEG) alone or in addition to a targeting peptide. GNPs were incubated with HeLa and MDA-MB-231 cells. This was followed by quantification of GNPs in cells and microscopy. PEG, which increases tumour interstitial tissue targeting but decreases cancer cell entry, was found to reduce cell entry when used to coat GNPs alone. GNPs coated with peptides and PEG had improved cell entry for all GNP sizes in HeLa cells and for 14 nm GNPs in MDA-MB-231 cells. Preliminary results show therapeutic enhancement with 50 nm NPs in an orthvoltage photon energy of 220 kVp for HeLa cells. Prospective therapeutic improvement with the same NPs will be studied using the more commonly used megavoltage photon energy of 6 MVp. Conclusion: Since cell targeting peptides improve NP entry into cells, there are improved radiation results for an orthvoltage photon energy. The same is expected for a megavoltage photon energy. Results from this study may be used to design NPs with longer blood circulation times and improved cancer cell entry. Such an optimized design will advance the clinical use of NP-based platforms in radiation therapy.
Conference Proceedings from RTi3 2015/Journal of Medical Imaging and Radiation Sciences 46/S1 (2015) S2-S30
S3