Implementation Science in Radiation Oncology: Case Study for Liver SBRT.

Abstract

The translation of research into clinical practice is challenging and implementation science is becoming as important as the trial design and development. Implementation science methodologies have been shown to reduce research-to-practice gap in other clinical settings. This is especially true for the field of Radiation Oncology where modern hypofractionated techniques, like Stereotactic Ablative Body Radiotherapy for Liver are at a high risk of over enthusiastic implementation as well as underutilization. We present the results of a multicomponent implementation methodology utilized to develop our Liver SBRT program as a model to safely translate a complex technology into clinical practice. After review of literature and market research a setup was created with focus on machine requirements, immobilization devices, motion management techniques and QA techniques. Clinical tools in the form of checklists were developed for patient selection, simulation along with image fusion, target delineation, planning (conformity indices, dose constraint criteria) and treatment delivery. All patients were treated on Truebeam® after Bodyfix® immobilization with plastic wrap. Planning was completed on Eclipse TPS with dose constraints and conformity guidelines defined per the RTOG 1112 and TG 101. Clinical outcomes including clinical and imaging follow-up for tumor control and toxicity were recorded. For this report, all patients treated were reviewed and compared to published data to assess the success of the implementation methodology. A total of 64 consecutive Patients treated with liver SBRT at Dignity Health Cancer Institute (DHCI) were eligible for the study. 58 patients treated for primary liver malignancies were included in this analysis to assess outcomes including control of disease and toxicity to compare to the published literature. Median follow up for these patients 6.5 months (4-46mnths). Median GTV volume was 38.7cc (0.1cc-2056.1 cc), median PTV volume was 159.35 cc (21.5cc-2673.5cc). Median SBRT prescription dose was 50 Gy/5 fractions (35-50 Gy). Median Liver- GTV was 1595.8 cc(770.7cc-2983.0cc). Following toxicities were noted- Grade 1- 10.3%, Grade 2 - 1.72%, Grade 3- 3.44%. No Grade 4 toxicity was noted. 1 year LC rate was 96.6%. 8.6% showed out of field liver failure and 6.9% developed distant metastasis. These results were compared to the current published literature and are shown to be comparable. Strong and well thought out Implementation methodologies can ensure reproducing results in clinical practice, comparable to the controlled environment of trials. These are crucial in translation of clinical trials utilizing advanced technologies to promote the culture of safety in clinical practice of Radiation Oncology. Regular assessment and tracking of clinical outcomes can be used as Quality markers for directing care and reimbursements for future.