Pelvic prehabilitation: pelvic exercises assist in minimizing inter-fraction sacral slope variability during radiation therapy

Introduction: Prehabilitation for radiation therapy is not well studied. Retrospective data shows variability in set-up positioning of patients during daily pelvic RT. We hypothesize that a brief structured daily exercise regimen is feasible for subjects to perform before RT and may minimize variability in positioning as measured by sacral slope angles (SSA) on lateral views. Determining feasibility and effectiveness of these exercises in decreasing set-up variability has clinical implications, both for targeting treatment sites and preventing adverse effects. Methods: Subjects in the exercise intervention condition (n=8, 8 F) performed a structured daily hip exercise regimen throughout the duration of RT, and subjects in the historical control condition (n=20, 17 F, 3 M) had usual care. For each patient, SSA measurements were compared to SSA measurements from the simulation CT for 5 weeks during RT. The extent of variability of measurements between two conditions was studied using a linear mixed model. For all patients in both conditions, the same two readers independently measured SSA to compare angles on day of simulation against the angles measured from each day of RT. Results: The average variation in SSA for intervention condition was 0.913° (±0.582°), with range among patients 0.57°-1.3°. The average variation for control condition was 2.27° (±1.43°), with range among patients 1.22° - 5.09°. The difference between two conditions was statistically significant (p=0.0019). Comparison of SSA variation between conditions demonstrated a statistically significant difference at each week (wk 1: p = 0.0071, wk 2: p = 0.0077, wk 3: p = 0.011, wk 4: p = 0.005, wk 5: p = 0.0079). The exercise intervention condition had no significant variation between week 1 and later weeks (wk 2: p = 0.876, wk 3: p = 0.741, wk 4: p = 0.971, wk 5: p = 0.397). The control condition showed greater SSA variation between week 1 and later weeks (wk 2: p = 0.868, wk 3: p = 0.915, wk 4: p = 0.015, wk 5: p = 0.224), with significant variation between weeks 1 and 4. No subject reported any adverse effects. Conclusion: We observed a significant decrease in sacral slope variability in our exercise cohort as compared to historical controls. SSA variation for control condition increased over the course of treatment with significant difference noted between week 1 and 4. A larger clinical trial is required to evaluate the potential clinical benefits of a structured daily exercise regimen during pelvic RT. References: Silver JK, Baima J. Cancer prehabilitation: an opportunity to decrease treatment-related morbidity, increase cancer treatment options, and improve physical and psychological health outcomes. American journal of physical medicine & rehabilitation. 2013 Aug 1;92(8):715-27. Lukez A, O’Loughlin L, Bodla M, Baima J, Moni J. Positioning of port films for radiation: variability is present. Medical Oncology. 2018 May 1;35(5):77. Kwon JW, Huh SJ, Yoon YC, Choi SH, Jung JY, Oh D, Choe BK. Pelvic bone complications after radiation therapy of uterine cervical cancer: evaluation with MRI. American Journal of Roentgenology. 2008 Oct;191(4):987-94. Stubblefield MD. Radiation fibrosis syndrome: neuromuscular and musculoskeletal complications in cancer survivors. PM&R. 2011 Nov 1;3(11):1041-54

Positioning of Patients for Pelvic Radiation: Variability Across Treatment

Objectives: We aimed to determine the variability in position of the pelvis for patients while receiving daily radiation treatments for pelvic malignancies. Design: Therapeutic radiation targets lymph nodes that lie along the curvature of the sacrum. Any change in pelvic tilt could inadvertently move these targets in or out of the radiation field. This variability has clinical significance both to target cancerous lymph nodes and avoid healthy sacrum. To better understand this variability, we observed trends in the change in the sacral slope. This measurement was chosen because it is an objective radiographic finding, there is no significant difference between men and women, and joint replacement does not appear to change this measurement. Twenty subjects were identified from patients receiving whole pelvis radiation for at least four weeks. CT simulator images and lateral radiographs obtained as part of standard radiation care were reviewed. We manually calculated this measurement with sloping lines drawn with computer graphics on the same single lateral view daily for the course of radiation per subject. Results: Compared to the initial imaging, the average sacral slope variation across all 20 subjects was 2.27 degrees, with a standard deviation of 1.43, and average variation among patients ranged from 1.22-5.09 degrees. Variation in sacral slope across all 20 subjects from one treatment day to the next was 2.05 degrees, with a standard deviation of 1.47, and ranged from 0.97-3.21 degrees. Conclusions: Despite the best efforts of the provider, there may be some variability in the daily pelvic position of the patient between fractions. This is clinically important because presacral lymph nodes are part of the radiation target volume and sacral fractures are a potential adverse effect of radiation treatment. Exercises for pelvic relaxation could be explored to potentially reduce this variability

Imaging and Neuro-Oncology Clinical Trials of the National Clinical Trials Network (NCTN)

Imaging in neuro-oncology clinical trials can be used to validate patient eligibility, stage at presentation, response to therapy, and radiation therapy. A number of National Clinical Trials Network trials illustrating this are presented. Through the Imaging and Radiation Oncology Core’s quality assurance processes for data acquisition and review, there are uniform data and imaging sets for review. Once the trial endpoints have been analyzed and published, the clinical trial information including pathology, imaging, and radiation therapy objects can be moved to a public archive for use by investigators interested in translational science and the application of new informatics tools for trial analysis

Acquisition and Management of Data for Translational Science in Oncology

Oncology clinical trials provide opportunity to advance care for patients with cancer. Bridging basic science with bedside care, cancer clinical trials have brought new and updated scientific knowledge at a rapid pace. Managing subject data in translation science requires a sophisticated informatics infrastructure that will enable harmonized datasets across all areas that could influence outcomes. Successful translational science requires that all relevant information be made readily available in a digital format that can be queried in a facile manner. Through a translational science prism, we look at past issues in cancer clinical trials and the new National Institutes of Health/National Cancer Institute initiative to address the need of database availability at an enterprise level

Modern Clinical Trials in Radiation Oncology

Clinical trials in radiation oncology have improved our translational science and patient care. All patients referred to departments of radiation oncology can be invited to participate in a clinical trial with multiple venues. Study endpoints can include intradepartmental endpoints to improve workflow and patient access as well as interdepartmental clinical translational trials that include the National Clinical Trials Network (NCTN) and industry. The quality of the trial is important to trial outcome and influences interpretation of the results of the study and how the results can be applied to patient care moving forward. Clinical trials in radiation oncology to date have accomplished much, however many important questions remain as patient care matures and systemic therapies become more sophisticated and associated with specific biomarkers and cellular expression products. In this chapter we review the history of clinical trials in radiation oncology and review the current status of the structure of quality assurance in clinical trials. We will review unanswered questions and areas to study in each disease area and how to design strategy for trials to address modern unmet needs in our discipline

The Future of Proton Therapy

Proton therapy is increasing in utilization worldwide at a rapid rate. With process improvements in costs, footprints, and continued advances in the delivery of care, including intensity modulation and image guidance, proton therapy may evolve into standard treatment with photon radiation therapy. This chapter reviews process improvements in proton therapy and the application in modern care

Prehabilitation for patient positioning: pelvic exercises assist in minimizing inter-fraction sacral slope variability during radiation therapy

Reproducible patient positioning is essential for precision in radiation therapy (RT) delivery. We tested the hypothesis that a structured daily pre-treatment stretching regimen is both feasible and effective for minimizing variability in positioning, as measured by sacral slope angles (SSA). Eight female subjects undergoing pelvic radiotherapy performed a structured daily hip exercise regimen (extension and external rotation) immediately prior to both simulation imaging and daily treatment, throughout their RT course. This exercising cohort was compared to a retrospective review of 20 subjects (17 women and 3 men) undergoing RT, who had usual care. SSA measurements from daily pre-treatment imaging were compared to SSA measurements from the simulation CT. The average variation in SSA among the intervention subjects was 0.91 degrees (+/- 0.58 degrees ), with a range among subjects of 0.57 degrees -1.27 degrees . The average variation for the control subjects was 2.27 degrees (+/- 1.43 degrees ), ranging 1.22 degrees -5.09 degrees . The difference between the two groups was statistically significant (p = 0.0001). There was a statistically significant SSA variation between groups at each week of treatment. There was no significant variation among the intervention subjects between week 1 and later weeks, whereas subjects in the control group demonstrated significant SSA variation between week 1 and later weeks. We demonstrated a significant decrease in the variability of SSA by implementing a simple pre-treatment exercise program, while control subjects exhibited increasing variation in SSA over the course of treatment. We conclude that there is a potential benefit of prehabilitation during pelvic RT; however, a larger randomized control trial is required to confirm the findings.Clinical Trial: This research project was approved by the University of Massachusetts Medical School IRB (IRB ID H00012353) on January 21, 2017. The study is listed on ClinicalTrials.gov, provided by the U.S. National Library of Medicine, found with identifier NCT03242538

Potential Role of the Quality Assurance Review Center Platform in Global Radiation Oncology

The 2014 World Health Organization (WHO) Cancer Report describes an alarming growth in the cancer burden worldwide and underscores that, of the 14 million new cases of cancer and 8.2 million cancer-related deaths per year, 60% and 70%, respectively, occur in low-income and middle-income countries (LMICs). These countries are the least capable of dealing with cancer without some form of collaboration. The disparities in cancer-related deaths in part reflect poignant underlying inequalities in access to radiation oncology services; also, a majority of the population groups that experience disparities is significantly underrepresented in cancer clinical trials. One way to narrow this divide in cancer-related services is by including minorities, or populations from diverse backgrounds and resource-poor settings, in clinical trials. In recent publications, we have highlighted the enormous potential of information and communication technologies (ICTs)—technologies used in the transmission, manipulation, and storage of data by electronic means, including the internet, mobile phone systems, broadcast radio, and TV systems—in catalyzing high-impact international collaborations in global radiation oncology. Here, we describe the role of the ICT-powered Quality Assurance Review Center (QARC) platform in global radiation oncology care, research, and education, with the perspective of radiation oncologists at 8 institutions in East and West Africa

Positioning of port films for radiation: variability is present

PURPOSE: Pelvic radiation treatment demands precision and consistency in patient setup for efficacy of therapy and to limit radiation dosage to normal tissue. Despite the use of immobilization devices and positioning techniques, there is still concern for variation in daily setup. The purpose of this retrospective study was to determine the presence and degree of variation in sacral slope in 20 subjects receiving radiation therapy for pelvic malignancies. METHODS: Each of the 20 subjects received between 20 and 25 fractions of external beam radiation treatment to the pelvis. The sacral slope was measured on each of the daily port films taken prior to treatment and compared to the sacral slope angle measured on the initial treatment planning simulation digitally reconstructed radiographic imaging. RESULTS: Compared to this initial imaging, the average sacral slope variation across all 20 subjects was 2.27 degrees (+/- 1.43 degrees ), and the average variation among patients ranged from 1.22 degrees to 5.09 degrees . Variation in sacral slope across all 20 subjects from one treatment day to the next was 2.05 degrees (+/- 1.47 degrees ), and ranged from 0.97 degrees to 3.21 degrees . CONCLUSIONS: This study demonstrates that despite the rigorous use of immobilization devices, there still exists day-to-day variation in sacral slope angle between treatment days and compared to initial baseline imaging off which the treatment plan is developed. There is an on-going study at our institution with an attempt to reduce this variation by offering exercises prior to radiation

Dosimetric impact of the AeroForm tissue expander in postmastectomy radiation therapy: an ex vivo analysis

PURPOSE: To evaluate the effect of the AeroForm (AirXpanders Inc, Palo Alto, CA) tissue expander on the dose distribution in a phantom from a simulated postmastectomy radiation treatment for breast cancer. METHODS AND MATERIALS: Experiments were conducted to determine the effect on the dose distribution with the metallic reservoir irradiated independently and with the entire AeroForm tissue expander placed on a RANDO phantom (The Phantom Laboratory, Salem, NY). The metallic reservoir was irradiated on a block of solid water with film at various depths ranging from 0 to 8.2 cm from the surface. The intact 400 cc AeroForm was inflated to full capacity and irradiated while positioned on a RANDO phantom, with 12 optically stimulated luminescent dosimeters (OSLDs) placed at clinically relevant expander-tissue interface points. RESULTS: Film dosimetry with the reservoir perpendicular to film reveals 40% transmission at a depth of 0.7 cm, which increases to 60% at a depth of 8.2 cm. In the parallel position, the results vary depending on which area under the reservoir is examined, indicating that the reservoir is not a uniformly dense object. Testing of the intact expander on the phantom revealed that the average percent difference (measured vs expected dose) was 2.7%, sigma = 6.2% with heterogeneity correction and 3.7%, sigma = 2.4% without heterogeneity correction. The only position where the OSLD readings were consistently higher than the calculated dose by \u3e 5% was at position 1, just deep to the canister at the expander-phantom interface. At this position, the readings varied from 5.2% to 14.5%, regardless of heterogeneity correction. CONCLUSIONS: Film dosimetry demonstrated beam attenuation in the shadow of the metallic reservoir in the expander. This decrease in dose was not reproduced on the intact expander on the phantom designed to replicate a clinical setup. Inc