ABSTRACT
Background and purpose: Adaptive radiotherapy (ART) in locally advanced cervical cancer (LACC) has shown promising outcomes. This study investigated the feasibility of cone-beam computed tomography (CBCT)-guided online ART (oART) for the treatment of LACC. Material and methods: The quality of the automated radiotherapy treatment plans and artificial intelligence (AI)-driven contour delineation for LACC on a novel CBCT-guided oART system were assessed. Dosimetric analysis of 200 simulated oART sessions were compared with standard treatment. Feasibility of oART was assessed from the delivery of 132 oART fractions for the first five clinical LACC patients. The simulated and live oART sessions compared a fixed planning target volume (PTV) margin of 1.5 cm around the uterus-cervix clinical target volume (CTV) with an internal target volume-based approach. Workflow timing measurements were recorded. Results: The automatically-generated 12-field intensity-modulated radiotherapy plans were comparable to manually generated plans. The AI-driven organ-at-risk (OAR) contouring was acceptable requiring, on average, 12.3 min to edit, with the bowel performing least well and rated as unacceptable in 16 % of cases. The treated patients demonstrated a mean PTV D98% (+/-SD) of 96.7 (+/- 0.2)% for the adapted plans and 94.9 (+/- 3.7)% for the non-adapted scheduled plans (p<10-5). The D2cc (+/-SD) for the bowel, bladder and rectum were reduced by 0.07 (+/- 0.03)Gy, 0.04 (+/-0.05)Gy and 0.04 (+/-0.03)Gy per fraction respectively with the adapted plan (p <10-5). In the live.setting, the mean oART session (+/-SD) from CBCT acquisition to beam-on was 29 +/- 5 (range 21-44) minutes. Conclusion: CBCT-guided oART was shown to be feasible with dosimetric benefits for patients with LACC. Further work to analyse potential reductions in PTV margins is ongoing.
ABSTRACT
BACKGROUND: Access to high quality radiotherapy (RT) continues to be a major issue across Africa with Africa having just 34% of its optimal capacity. METHODS: We co-developed a survey with clinical, academic and policy stakeholders designed to provide a structured assessment of the barriers and enablers to RT capacity building in Africa. The survey covered nine key themes including funding, procurement, education and training. The survey was sent to RT professionals in 28 countries and the responses underwent qualitative and quantitative assessment. RESULTS: We received completed questionnaires from 26 African countries. Funding was considered a major issue, specifically the lack of a ring fenced funds from the Ministry of Health for radiotherapy and the consistency of revenue streams which relates to a lack of prioritisation for RT. In addition to a significant shortfall in RT workforce disciplines, there is a general lack of formal education and training programmes. 13/26 countries reported having some IAEA support for RT for education and training. Solutions identified to improve access to RT include a) increasing public awareness of its essential role in cancer treatment; b) encouraging governments to simplify procurement and provide adequate funding for equipment; c) increasing training opportunities for all radiotherapy disciplines and d) incentivizing staff retention. CONCLUSION: This survey provides unique information on challenges to delivering and expanding radiotherapy services in Africa. The reasons are heterogonous across countries but one key recommendation would be for national Cancer Control plans to directly consider radiotherapy and specifically issues of funding, equipment procurement, servicing and training. POLICY SUMMARY: The study demonstrates the importance of mixed methods research to inform policy and overcome barriers to radiotherapy capacity and capability in LMICs.
Subject(s)
Developing Countries , Humans , AfricaABSTRACT
Online adaptive radiotherapy (oART) is an emerging advanced treatment option for cancer patients worldwide. Current oART practices using magnetic resonance (MR) and cone beam computed tomography (CBCT) based imaging are resource intensive and require physician presence, which is a barrier to widespread implementation. Global evidence demonstrates Radiation Therapists (RTTs) can lead the oART workflow with decision support tools and on 'on-call' caveats in a 'clinician-lite' approach without significantly compromising on treatment accuracy, speed or patient outcomes. With careful consideration of jurisdictional regulations and guidance from the multi-disciplinary team, RTTs can elevate beyond traditional scopes of practice. By implementing robust and evidence-based credentialing activities, they enable service sustainability and expand the real-world gains of adaptive radiotherapy to a greater number of cancer patients worldwide. This work summarises the evidence for RTT-led oART treatments and proposes a pathway for training and credentialing.
