Breast Cancer Research and Treatment

, Volume 115, Issue 2, pp 423–428

Pattern of metastatic spread in triple-negative breast cancer

Authors

  • Rebecca Dent
    • Department of Medical Oncology, Sunnybrook Health Sciences CenterUniversity of Toronto
  • Wedad M. Hanna
    • Department of Medical Oncology, Sunnybrook Health Sciences CenterUniversity of Toronto
  • Maureen Trudeau
    • Department of Medical Oncology, Sunnybrook Health Sciences CenterUniversity of Toronto
  • Ellen Rawlinson
    • Women’s College Research Institute, Women’s College HospitalUniversity of Toronto
  • Ping Sun
    • Women’s College Research Institute, Women’s College HospitalUniversity of Toronto
    • Women’s College Research Institute, Women’s College HospitalUniversity of Toronto
Epidemiology

DOI: 10.1007/s10549-008-0086-2

Cite this article as:
Dent, R., Hanna, W.M., Trudeau, M. et al. Breast Cancer Res Treat (2009) 115: 423. doi:10.1007/s10549-008-0086-2

Abstract

Purpose The prognosis of women with triple-negative breast cancers (defined as cancers that are estrogen receptor-negative, progesterone receptor-negative and HER2/neu negative) is poor, compared to women with other subtypes of breast cancer. It is proposed that the underlying difference in recurrence rates may be explained in part by different routes of metastatic spread. Experimental design We studied a cohort of 1608 patients diagnosed with breast cancer, diagnosed between January 1987 and December 1997 at Women’s College Hospital in Toronto. Triple-negative breast cancers were defined as those that were estrogen receptor-negative, progesterone receptor-negative and HER2/neu-negative. We compared the incidence rates of metastatic spread to bone and to other (non-bone) organs in women with triple-negative and other forms of breast cancer. Results Of the 1,608 patients, 180 (11.2%) had triple-negative breast cancer. The 1608 women were followed for a median of 9.0 years (range 0.1–19 years). Compared to other patients, those with triple-negative breast cancer had an increased likelihood of distant recurrence over the study period (adjusted hazard ratio (HR) 1.9; 95% CI: 1.5–2.5, P < 0.0001). The relatively poor prognosis was apparent in the five years after diagnosis (HR 2.9; 95% CI: 2.1–3.9; P = 0.0001) but not thereafter (HR 0.5; 95% CI: 0.2–1.1; P = 0.07). In particular, women with triple-negative breast cancer were four times more likely to experience a visceral metastasis within five years of diagnosis than those with other types of cancer (HR 4.0; 95% CI: 2.7–5.9; P < 0.0001). The rates of bone metastases were comparable for triple-negative and for other forms of cancer in this time period (HR 0.8; 95% CI: 0.4–1.6 P = 0.5). Conclusions The excess risk of distant recurrence in triple-negative breast cancers, versus other forms of cancer, is attributable in large part to an excess of visceral metastases in the first five years following diagnosis.

Keywords

Triple-negativeBasal-likeBreast cancerMetastases

Abbreviations

HR

Hazard ratio

ER

Estrogen receptor

PR

Progesterone receptor

HBBC

Henrietta Banting database

CI

Confidence interval

Copyright information

© Springer Science+Business Media, LLC. 2008