Highly significant improvement in guideline adherence, relapse-free and overall survival in breast cancer patients when treated at certified breast cancer centres: An evaluation of 8323 patients

Abstract

Objectives: Certified multi-disciplinary breast cancer centres (CBCs) have been established worldwide. Development of CBCs, guideline-adherent systemic therapy and surgical management should now show an impact on outcomes. This analysis aimed to investigate whether guideline adherence (GA) rates, relapse-free survival (RFS) and overall survival (OS) have significantly improved at CBCs compared to the pre-certification period.

Materials and methods: 8323 patients with primary breast cancer were treated in 17 German CBCs, which had been certified between 2003 and 2007 [2003 (n = 1), 2004 (n = 6), 2005 (n = 3), 2006 (n = 6) and 2007 (n = 1)]. 3544 patients (42.6%) were treated before certification and 4779 patients (57.4%) after certification.

Results and conclusion: A highly significant (p < 0.001) difference in 100%-GA was found between the various hospitals before certification (min 25.0%; max 54.6%). In 2008, when all participating hospitals were certified, the GA rate was 61.8% (min 39.5%, max 74.4%) and 69.2% (min 45.9%, max 86.4%) for patients <75 y (n = 6675). The difference between pre-certification 100%-GA (46.9%) and post-certification (57.2%) was highly significant (p < 0.001). RFS and OS were both significantly better after certification compared to the pre-certification period (RFS: HR = 0.79; 95% CI: 0.68-0.92; p = 0.003; OS: HR = 0.75; 95% CI: 0.65-0.85; p < 0.001). 5-year RFS (OS) of patients <75 y was 89.6% (85.4%) pre-certification and 91.4% (89.5%) post-certification. Since improvement in GA and outcomes correlated as well, GA remains a highly significant prognostic factor for RFS and OS regardless of NPI, intrinsic subtype and adjuvant systemic therapy. This suggests that the certification process is strongly associated with improvements in outcome.

Keywords: Benchmarking; Breast cancer; Certified breast cancer centres; Guideline adherence; Overall survival; Quality assurance; Relapse-free survival.