IARC 60th Anniversary - 19-21 May 2026
Session : 20/05/26 - Posters
Quality of breast cancer treatment in Switzerland 2020-2022– a population-based cancer registry study
ABO EL ELA A. 1,2, WILDISEN L. 1,2, EGGEBRECHT G. 1,2, LEO C. 3, RAUH C. 4, HUOBER J. 5, LOREZ M. 1,2, WEBER M. 1,2, STEIGMILLER K. 1,2, PEDERSEN E. 1,2, STAEHELIN K. 1,2
1 National Agency for Cancer Registration (NACR), Zürich, Switzerland; 2 National Institute for Cancer Epidemiology and Registration (NICER), Zürich, Switzerland; 3 Breast Center, Cantonal Hospital Baden, Baden, Switzerland; 4 Breast Center, University Hospital Zurich, Zürich, Switzerland; 5 Breast Center, Health Ostschweiz, St. Gallen, Switzerland
Background: In Switzerland, the quality of breast cancer treatment is regularly assessed and monitored in certified cancer centers. However, less is known about the overall quality of care provided by all healthcare providers. Analysing population-based cancer data collected in cancer registries can fill this gap.
Objectives: This study aims to evaluate the quality of breast cancer treatment in Switzerland using nation-wide cancer registry data.
Methods: Data from the National Agency for Cancer Registration in Switzerland, covering all Swiss cantons was used, including all cases of invasive primary breast cancer (ICD-10 C50) diagnosed from 2020 to 2022. The frequency of treatment decisions by tumour boards, types of treatments administered and the adherence to guidelines were analysed descriptively, stratified by age and stage at diagnosis.
Results: Between January 2020 and December 2022, 20,660 cases of invasive breast cancer were diagnosed in Switzerland. Treatment decisions were made by a tumour board in 85% of cases. The younger the patient, the more frequent were treatment decisions at tumour boards: 87% of patients aged <50 years versus 78% of patients aged ≥80 years. 88% of all patients underwent surgery, 64% received radiotherapy, 34% chemotherapy, 64% hormone therapy, and 17% targeted therapy/immunotherapy, with differences according to the stage at diagnosis and tumour subtype. Among all surgical treatments, 73% were breast-conserving surgeries, 7% nipple-/skin preserving mastectomies and 20% total mastectomies. The analysis to the treatment guidelines adherence showed that 86% of all patients received radiotherapy after breast-conserving surgery, 80% of patients with triple-negative and 77% with HER2-positive breast cancer received chemotherapy, 73% of patients with hormone receptor-positive breast cancer received endocrine therapy and 70% of patients with HER-2 positive breast cancer received targeted therapy/immunotherapy. The adherence to guidelines differed by patient age with a lower proportion among patients aged over 80 years.
Conclusion: This population-based study shows that breast cancer treatment in Switzerland is of good quality but could still be improved. The nation-wide frequency of treatment decisions made at tumor boards and of some guideline-based therapies are below the recommendations for certified centers. However, underreporting may also have played a role.