ESTRO 2024 - Abstract Book

S2759

Interdisciplinary - Global health

ESTRO 2024

3255

Proffered Paper

Quantifying global demand, supply and access to proton beam therapy

Mohammad Akash, Ahmed Salem, Fanar Alsamarat

Hashemite University, Faculty of Medicine, Zarqa, Jordan

Purpose/Objective:

Supply and access to proton beam therapy (PBT) is limited globally, particularly in low-income (LIC) and lower middle-income countries (LMIC) where demand is high due to the rates of base of the skull and paediatric malignancies. This study aimed to investigate the global demand and supply of PBT and quantify geographical barriers to access.

Material/Methods:

We first quantified the number and proportion of new cancer cases that could benefit from radiotherapy and PBT globally (global demand). To enable this, the incidence rates for 24 tumour sites across 185 countries were extracted from the 2020 GLOBOCAN database (Sung et al. 2021). Radiotherapy Utilisation Rates (RTU) were defined for each tumour site as per Delaney et al. (Clin Oncol 2015). Proton Therapy Utilisation Rates (PTU) were defined for each tumour site as per Burnet et al. (Br J Radiol. 2022). For PTU estimation, we assumed that all paediatric malignancies treated with curative-intent radiotherapy (excluding leukaemia) would benefit from PBT due to reduced growth impairment. We utilised the benefit percentage as per Burnet et al. for reduced toxicity as the sole mechanism of benefit from PBT for adult malignancies. We then quantified radiotherapy and PBT supply globally. Data on the number of radiotherapy Megavoltage Machines (MVM) were retrieved from the Directory of Radiotherapy Centres (DIRAC). Data on the number of Proton Treatment Rooms (PTR) in all operational PBT centres (N=109) globally as of July 2023 were retrieved form the Particle Therapy Co-Operative Group (PTCOG) webpage. We calculated the supply and demand disparities for PBT and RT. Countries were categorised into different income groups as per the World Bank 2024 fiscal year classifications for Gross National Income (GNI) per capita, calculated using the World Bank Atlas method. Lastly, we quantified geographical barriers for access to PBT. We utilised Google Maps geocoding API to geocode the addresses of each PBT centre. Subsequently, we calculated the average weighted travelling distance between each PBT centre and the most populated administrative divisions within each country with PBT coverage. For countries without PBT, we calculated the average weighted distance to the nearest PBT centre. The mean global PTU was found to be 4.52% (95% confidence interval: ±0.338%) corresponding to an estimated number of cancer cases of 751,001 to 872,304 (95% C.I.). Mean PTU was highest in LMIC (N=298,024, 7.33%), which was more than three times that of the PTU of high-income countries (HIC; N=186,419, 2.42%). Among the 185 countries studied, PTU ranged from as low as 1.61% in New Zealand to as high as 10.39% in Bangladesh. On the other hand, the mean global RTU was found to be 47.23% (95% C.I. ±0.461) corresponding to an estimated number of cancer cases of 8,404,779 to 8,570,470(95% C.I.). RTU was highest in LIC (N=229,660, 49.07%) and lowest in upper middle-income countries (UMIC; N=3,529,062, 45.76%) with much less discrepancy compared to PTU. Critically, we found that the PTU decreases as the income per capita increases. However, no direct correlation was observed between RTU and income level; figure 1A-B. Results: