Abstract P4-12-26: Partial breast irradiation, simultaneous integrated boost and regional nodal irradiation: A UK private provider approach to maximising patient access to advanced breast radiotherapy
Authors: Kechagioglou Penny , Bowler Mark , Williams Trevor 
Published: March 2020

Introduction: Post-operative whole breast radiotherapy reduces ipsilateral recurrence by 20% and 15-year breast cancer mortality by 5.4%. Technique offerings should evolve to maximise clinical outcomes whilst reducing toxicities. Partial breast irradiation (PBI) reduces skin toxicity while being as effective as whole breast radiotherapy, Simultaneous Integrated Boost (SIB) shortens treatment while offering better tumour control than sequential boost and regional nodal irradiation (RNI) with VMAT IMRT provides excellent target dose conformity. Access to advanced radiotherapy in UK lags behind demand, due to workforce shortages and time pressures for planning and peer review.

Background: GenesisCare is the global leader in oncology services with 12 UK oncology centres, equipped with latest radiotherapy technologies and offering IMRT/VMAT for RNI (NICE guidelines), SIB (IMPORT-HIGH) and PBI (GEC-ESTRO, IMPORT LOW). GenesisCare UK (GCUK) collaborates with breast oncologists and surgeons who work in the National Health Service and who utilise those techniques inconsistently. This retrospective study aims at identifying patient eligibility for those techniques, measure uptake and devise strategies to increase patient access.

Method: Patients referred for radiotherapy between November 2018 and May 2019 were screened for PBI, SIB or RNI eligibility. We focused on our Oxford and Cambridge centres because clinicians practising there are familiar with those techniques from their NHS practice. Minimum patient datasets, histology/imaging reports and multi-disciplinary team (MDT) meeting outcomes were reviewed. Patient eligibility was evaluated against uptake.

Results: 408 cases were treated across the network, with 39 cases in Oxford and Cambridge. Two patients with stage IV disease and one with DCIS were excluded and remaining 36 patients were evaluated as per table 1.

Table 1 Technique eligibility vs utilisationTechniqueEligible (%)Eligible & Offered (%)Eligible Not offered (%)Not eligible (%)PBI12 (33)1 (8)11 (92)24 (67)SIB15 (42)3 (20)12 (80)21 (58)RNI5 (14)5 (100)031 (86)

Only 1 of 12 PBI eligible patients were offered PBI (RTOG zero acute skin toxicity). From the remaining 11 patients, 1 had grade 4 toxicity and received oral antibiotics for skin infection, 4 had grade 2, 5 had grade 1 and 1 had zero toxicity. All high-risk patients had RNI with VMAT, but only 20% eligible for a boost were offered SIB. They had sequential boost with treatment prolongation by 5-8 days.

Summary and Next Steps

Access to breast radiotherapy in UK lags behind demand, especially for advanced techniques like PBI, SIB and RNI. At GCUK, we set out our vision for the Breast Service of the Future (SOF), an approach that draws from best practice and evidence-based radiotherapy. We believe that patients should be offered a personalised radiotherapy approach and we have taken steps to maximise patient access to advanced breast radiotherapy (table 2).

Table 2 Breast SOF StrategyActionEnablers1. Key Opinion Leader engagement, clinical protocol development, whole MDT approach to change including breast oncologists, surgeons, radiologists, eMDT & Peer Review process set upBreast SOF ConferenceContouring workshopsUK roadshowsIT and Innovation teams1. Internal staff training to advanced techniques for dosimetrists, radiographers and physicistsESTRO PBI and IGRT coursesContouring workshops1. Purchasing Auto-contouring software for Organs at risk and Internal Mammary Chain, creation of breast contouring atlasesClinician/staff training by GCUK clinical applications specialist1. Breast SOF journal development and circulation across the network (oncologists, surgeons, GPs, radiologists) to include evidence-based practice behind advanced radiotherapy techniquesBreast SOF Steering CommitteeBreast reference group and clinician engagement

Citation Format: Penny Kechagioglou, Mark Bowler, Trevor Williams. Partial breast irradiation, simultaneous integrated boost and regional nodal irradiation: A UK private provider approach to maximising patient access to advanced breast radiotherapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-12-26.