ESTRO 2022 - Abstract Book

S155

Abstract book

ESTRO 2022

The second example is the retrospective DBCG Heart study investigating the risk of RT associated heart disease in >22.000 irradiated breast cancer patients. A total of 204 cases were identified, and a case-control study demonstrated that using CT-based breast cancer RT leads to relatively low radiation doses to the heart. No association between RT and risk of ischemic heart disease could be identified at median 7.4 yr follow up (2). A third example is the DBCG RT Nation study collecting all RT plans used for loco-regional RT of 9.000 high-risk breast cancer patients during 2008-2016. The planning CT scan, delineations of target volumes and organs at risk (OAR), treatment plans and dose distributions are stored in the national dose plan bank, the DcmCollab (3). Using these data, several studies are investigating e.g. adherence to DBCG RT guidelines, quality assurance of RT across departments, and dose distributions in selected targets and OAR (4,5). The last example is the prospective DBCG Center and Clinic for Late Effects (DCCL), which includes nationwide prospective collection of PRO from diagnosis to end of follow up in all Danish breast cancer patients, and the PRO results are collected into the DBCG database. The PRO collection is carried out through an app using internationally validated in addition to DBCG developed questionnaires at relevant time points according to the treatment provided. Importantly, the patient receives direct feedback through the app depending on the responses. The above initiatives are only feasible because every department in Denmark follows the DBCG guidelines with a high ambition and willingness for collaboration inside DBCG. Treating according to nationwide guidelines improves the quality of therapy for every patient, ensures that patients are treated as equal as possible, provides comfort to the doctor knowing that high-level therapy is used, and opens the possibility for documenting the outcome of modern therapy in large patient cohorts.

(1) Thorsen LBJ, Offersen BV, Danø H, et al. DBCG-IMN: A Population-Based Cohort Study on the Effect of Internal Mammary Node Irradiation in Early Node-Positive Breast Cancer. Journal of Clinical Oncology 2015

(2) Milo MLH, Møller DS, Nyeng TB, Hoffmann L et al. No correlation between radiation dose to cardiac substructures and coronary artery disease in early breast cancer patients: A DBCG case-control study, ESTRO 2021 abstract (3) Krogh SL, Lorenzen E, Hansen CR et al. Collecting Complete Radiotherapy Plan Data of 11,000+ Patients in a National Database, ESTRO 2022 abstract

(4) Refsgaard LR, Skarsø ER, Ravkilde T et al. Dose and volume of the heart and internal mammary lymph nodes in Denmark 2008-2016 (DBCG RT Nation study), ESTRO 2022 abstract

(5) Skarsø ER, Refsgaard LR, Ravkilde T et al. Parametrization of artery delineation and nationwide implementation in the DBCG RT Nation cohort, ESTRO 2022 abstract

Joint Symposium: ESTRO-ASTRO: Is integration with immunotherapy the new challenge for radiation oncologists?

SP-0181 Photon with immunotherapy/immunological consequences

S. Formenti

USA Abstract not available

SP-0182 Particle with immunotherapy/immunological consequences

TBC

Abstract not available

SP-0183 ESTRO-ASTRO: Is integration with immunotherapy the new challenge for radiation oncologists? Brachytherapy with immunotherapy

E. Van Limbergen 1

1 MAASTRO clinic1Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Develop, Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands Abstract Text Radiotherapy is known to stimulate the immune system through a process called immunogenic cell death (ICD). Extensive preclinical research has linked ionizing radiation to many diverse molecular signal pathways contributing to ICD, marking it as a strong ICD inducer. Examples include: release of ATP; exposure of calreticulin on the plasma membrane; interferon type I expression; and HMGB1 release etc. A combination of radiotherapy with immune stimulating agents is therefore rational.