Estimating the percentage of patients who might benefit from proton beam therapy instead of X-ray radiotherapy

Abstract

Objectives: High energy Proton Beam Therapy (PBT) commenced in England in 2018 and NHS England commissions PBT for 1.5% of patients receiving radical radiotherapy. We sought expert opinion on the level of provision. Methods: Invitations were sent to 41 colleagues working in PBT, most at one UK centre, to contribute by completing a spreadsheet. 39 responded: 23 (59%) completed the spreadsheet; 16 (41%) declined, arguing that clinical outcome data are lacking, but joined six additional site-specialist oncologists for two consensus meetings. The spreadsheet was pre-populated with incidence data from Cancer Research UK and radiotherapy use data from the National Cancer Registration and Analysis Service. ‘Mechanisms of Benefit’ of reduced growth impairment, reduced toxicity, dose escalation and reduced second cancer risk were examined. Results: The most reliable figure for percentage of radical radiotherapy patients likely to benefit from PBT was that agreed by 95% of the 23 respondents at 4.3%, slightly larger than current provision. The median was 15% (range 4–92%); consensus median 13%. The biggest estimated potential benefit was from reducing toxicity, median benefit to 15% (range 4–92%), followed by dose escalation median 3% (range 0 to 47%); consensus values were 12 and 3%. Reduced growth impairment and reduced second cancer risk were calculated to benefit 0.5 and 0.1%. Conclusions: The most secure estimate of percentage benefit was 4.3% but insufficient clinical outcome data exist for confident estimates. The study supports the NHS approach of using the evidence base, and developing it through randomised trials, non-randomised studies and outcomes tracking. Advances in knowledge: Less is known about the percentage of patients who may benefit from PBT than is generally acknowledged. Expert opinion varies widely. Insufficient clinical outcome data exists to provide robust estimates. Considerable further work is needed to address this, including international collaboration; much is already underway but will take time to provide mature data.

If we build it, will they come? Modeling of public hospital care requirements for the Australian Bragg Centre for Proton Therapy and Research

“…The National Health Service sought expert opinion in the United Kingdom in regard to the number of adult patients who would benefit from PBT. 11 These numbers are consistent, yet not over-represented, in our patient modeling (i.e., near absolute indication for PBT in chordomas and skull base tumors). 11 Our modeling data have estimated that 80% of adult patients with an eligible indication referred to RT would receive PBT.…”

“…11 These numbers are consistent, yet not over-represented, in our patient modeling (i.e., near absolute indication for PBT in chordomas and skull base tumors). 11 Our modeling data have estimated that 80% of adult patients with an eligible indication referred to RT would receive PBT. This accounts for outcomes of prospective comparative proton-to-photon treatment planning exercises to determine objectively the potential benefit of PBT for a given patient and the willingness of the patient to travel to receive treatment.…”

Risk of temporal lobe necrosis between proton beam and volumetric modulated arc therapies in patients with different head and neck cancers

“…In addition, the capacity of PBT may still be limited and therefore patient selection remains crucial. Also, access is not equitable in most countries and it needs to be clear that in a wide territory with a high incidence of NPC, patients can still be treated with gold-standard XRT without jeopardizing their outcomes [ 44 , 45 ].…”

Efficacy and safety of particle therapy for inoperable stage II-III non-small cell lung cancer: a systematic review and meta-analysis

“…Over the past two decades, particle therapy, mainly comprising carbon-ion radiotherapy (CIRT) and proton beam therapy (PBT), has been utilized for the treatment of various cancers, including lung cancer, and has shown encouraging clinical outcomes and acceptable toxicity [ 13 – 16 ]. It was estimated that approximately 13% of patients receiving curative radiotherapy might benefit from PBT [ 17 ]. Compared to photon radiotherapy, particle therapy has a better dose distribution [ 18 , 19 ], which is reflected in when a similar or higher dose is given to tumor tissue, the radiation dose exposed to normal tissue is lower or the same [ 20 ].…”