Affiliations 

  • 1 Faculty of Medicine, Julius Centre University of Malaya, University of Malaya, Lembah Pantai, Kuala Lumpur, Malaysia
  • 2 Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
  • 3 Department of Radiation Oncology, National Cancer Centre Singapore, Singapore, Singapore
  • 4 Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
  • 5 Breast Surgery Division, Department of Surgery, The University of Hong Kong, Pokfulam, Hong Kong
  • 6 Department of General Surgery, Tan Tock Seng Hospital, Singapore, Singapore
  • 7 Department of Surgery, Faculty of Medicine, University of Malaya, Lembah Pantai, Kuala Lumpur, Malaysia
  • 8 Clinical Oncology Unit, Faculty of Medicine, University of Malaya, Lembah Pantai, Kuala Lumpur, Malaysia
  • 9 Department of General Surgery, Singapore General Hospital, Singapore, Singapore
  • 10 Department of Hematology Oncology, National University Cancer Institute, National University Health System, Singapore, Singapore
  • 11 Department of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
Int J Cancer, 2015 Nov 15;137(10):2504-12.
PMID: 26018878 DOI: 10.1002/ijc.29617

Abstract

The value of adjuvant radiotherapy in triple-negative breast cancer (TNBC) is currently debated. We assessed the association between adjuvant radiotherapy and survival in a large cohort of Asian women with TNBC. Women diagnosed with TNBC from 2006 to 2011 in five Asian centers (N = 1,138) were included. Survival between patients receiving mastectomy only, breast-conserving therapy (BCT, lumpectomy and adjuvant radiotherapy) and mastectomy with radiotherapy were compared, and adjusted for demography, tumor characteristics and chemotherapy types. Median age at diagnosis was 53 years (range: 23-96 years). Median tumor size at diagnosis was 2.5 cm and most patients had lymph node-negative disease. The majority of patients received adjuvant chemotherapy (n = 861, 76%) comprising predominantly anthracycline-based regimes. In 775 women with T1-2, N0-1, M0 TNBCs, 5-year relative survival ratio (RSR) was highest in patients undergoing mastectomy only (94.7%, 95% CI: 88.8-98.8%), followed by BCT (90.8%, 95% CI: 85.0-94.7%), and mastectomy with radiotherapy (82.3%, 95% CI: 73.4-88.1%). The adjusted risks of mortality between the three groups were not significantly different. In 363 patients with T3-4, N2-3, M0 TNBCs, BCT was associated with highest 5-year RSR (94.1%, 95% CI: 81.3-99.4%), followed by mastectomy with radiotherapy (62.7%, 95% CI: 54.3-70.1%), and mastectomy only (58.6%, 95% CI: 43.5-71.6%). Following multivariable adjustment, BCT and mastectomy with radiotherapy remained significantly associated with lower mortality risk compared to mastectomy only. Overall, adjuvant radiotherapy was associated with higher survival in women aged <40 years, but not in older women. Adjuvant radiotherapy appears to be independently associated with a survival gain in locally advanced as well as in very young TNBC.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.