The influence of timing of radiation therapy following breast-conserving surgery on 10-year disease-free survival

Marissa C. van Maaren*, Reini W. Bretveld, Jan J. Jobsen, Renske K. Veenstra, Catharina G.M. Groothuis-Oudshoorn, Hendrik Struikmans, John H. Maduro, Luc J.A. Strobbe, Philip M.P. Poortmans, Sabine Siesling

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

16 Citations (Scopus)
50 Downloads (Pure)

Abstract

Background: The Dutch guidelines advise to start radiation therapy (RT) within 5 weeks following breast-conserving surgery (BCS). However, much controversy exists regarding timing of RT. This study investigated its effect on 10-year disease-free survival (DFS) in a Dutch population-based cohort.

Methods: All women diagnosed with primary invasive stage I-IIIA breast cancer in 2003 treated with BCS+RT were included. Two populations were studied. Population 1 excluded patients receiving chemotherapy before RT. Analyses were stratified for use of adjuvant systemic therapy (AST). Population 2 included patients treated with chemotherapy, and compared chemotherapy before (BCS-chemotherapy-RT) and after RT (BCS-RT-chemotherapy). DFS was estimated using multivariable Cox regression. Locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were secondary outcomes.

Results: Population 1 (n=2759) showed better DFS and DMFS for a time interval of >55 than a time interval of <42 days. Patients treated with AST showed higher DFS for >55 days (hazards ratio (HR) 0.60 (95% confidence interval (CI): 0.38-0.94)) and 42-55 days (HR 0.64 (95% CI: 0.45-0.91)) than <42 days. Results were similar for DMFS, while timing did not affect LRRFS and OS. For patients without AST, timing was not associated with DFS, DMFS and LLRFS, but 10-year OS was significantly lower for 42-55 and >55 days compared to <42 days. In population 2 (n=1120), timing did not affect survival in BCS-chemotherapy-RT. In BCS-RT-chemotherapy, DMFS was higher for >55 than <42 days.

Conclusions: Starting RT shortly after BCS seems not to be associated with a better long-term outcome. The common position that RT should start as soon as possible following surgery in order to increase treatment efficacy can be questioned.

Original languageEnglish
Pages (from-to)179-188
Number of pages10
JournalBritish journal of cancer
Volume117
Issue number2
DOIs
Publication statusPublished - 11 Jul 2017

Keywords

  • 10-year disease-free survival
  • Breast cancer
  • Breast-conserving surgery
  • Radiation therapy
  • Time interval

Fingerprint Dive into the research topics of 'The influence of timing of radiation therapy following breast-conserving surgery on 10-year disease-free survival'. Together they form a unique fingerprint.

Cite this