An interim analysis of outcome data from the UK Proton Overseas Programme

Abstract

Purpose or Objective The Proton Overseas Program (POP) was launched in 2008 by the National Health Service (NHS) to deliver high energy Proton Beam Therapy (PBT) abroad to UK patients until this became available in the UK (in 2018). The NHS used a systematic evidence based and prioritised approach. More than 10 years since its inception, we report the long term outcomes on patient groups who have accessed this programme; results compare favourably with other studies (1). Material and Methods Between 2008 and 2018, 1352 patients with eligible indications, from 46 centres across the UK, were referred for consideration of PBT. A national expert panel, adhering to approved criteria, established the appropriateness of PBT in each case. All cases were of sufficient performance status to travel, were appropriately staged and received treatment in experienced PBT centres. 1264 patients were approved (93.5 % of the referrals), 1096 (86.7%) were treated in North America and 168 (13.3%) were treated in Europe. Patient, tumour, treatment and follow-up data were collated in a centralised database. A Proton Clinical Outcomes Unit (PCOU) has been established to monitor this patient cohort as well as standardise and improve prospective outcome data collection for UK PBT patients going forward. Systematic follow-up data was available for 979 patients (77.1% of those approved for PBT). Mirroring the National Institute for Health and Care Excellence’s (NICE) definition of children, and Teenagers and Young adults (TYA), analysis has been conducted on the subgroups ≤25 vs >25 years old (y). Patients, disease and treatment characteristics are listed in Table 1. Results After a median follow-up of 34 months (range 6-123), the Local Control (LC) rate for the whole cohort is 85.3%; by age (≤25 y vs >25 y) LC rates are 87% for the younger group vs 78.8% for the older group. For tumours of the central nervous system (CNS), the LC rate is 84.1% (86.2% ≤ 25 y vs 79.2% > 25 y). For tumours outside the CNS the LC rate is 87.3% (88.1% in ≤ 25 y vs 75% in > 25 y). Further analysis on the major histological subgroups is listed in Table 1. The data show that LC is highest for craniopharyngioma (97.7%) in the CNS subgroup and for Ewing’s sarcoma (88.2%) in the body subgroup. Figure 1 illustrates the Kaplan-Meier survival estimates (95% Confidence Intervals) for the main groups. Conclusion The outcome of patients treated through the POP compares favourably with that reported in the literature (1). The POP has facilitated equitable access to PBT abroad for patients with complex needs from across the UK without disadvantaging patient outcome. The PCOU continues to collect data from these patients, as well as from patients who have been treated at the now established PBT service in UK. This prospective data registry will, over time, inform us further of the outcomes of patients treated with PBT to improve patient care.