Nodal staging affects adjuvant treatment choices in elderly patients with clinically node-negative, estrogen receptor–positive breast cancer

  • A. Laws Foothills Medical Centre, University of Calgary
  • R. Cheifetz BC Cancer, University of British Columbia
  • R. Warburton Providence Health Care, BC Cancer, University of British Columbia
  • C.E. McGahan BC Cancer, University of British Columbia
  • J.S. Pao University of British Columbia
  • U. Kuusk University of British Columbia
  • C. Dingee University of British Columbia
  • M.L. Quan University of Calgary
  • E. McKevitt University of British Columbia
Keywords: Breast cancer in elderly, sentinel lymph node biopsy, predictors of nodal positivity, adjuvant radiation, adjuvant endocrine therapy

Abstract

Background In response to Choosing Wisely recommendations that sentinel lymph node biopsy (slnb) should not be routinely performed in elderly patients with node-negative (cN0), estrogen receptor–positive (er+) breast cancer, we sought to evaluate how nodal staging affects adjuvant treatment in this population.

Methods From a prospective database, we identified patients 70 or more years of age with cN0 breast cancer treated with surgery for er+ her2-negative invasive disease during 2012–2016. We determined rates of, and factors associated with, nodal positivity (pN+), and compared the use of adjuvant radiation (rt) and systemic therapy by nodal status.

Results Of 364 patients who met the inclusion criteria, 331 (91%) underwent slnb, with 75 (23%) being pN+. Axil­lary node dissection was performed in 11 patients (3%). On multivariate analysis, tumour size was the only factor associated with pN+ (p = 0.007). Nodal positivity rates were 0%, 13%, 23%, 33%, and 27% for lesions preopera­tively sized at 0–0.5 cm, 0.5–1 cm, 1.1–2.0 cm, 2.1–5.0 cm, and more than 5.0 cm. Compared with patients assessed as node-negative, those who were pN+ were more likely to receive axillary rt (lumpectomy: 53% vs. 1%, p < 0.001; mastectomy: 43% vs. 2%, p < 0.001), and adjuvant systemic therapy (endocrine: 82% vs. 69%; chemotherapy plus endocrine: 7% vs. 2%, p = 0.002).

Conclusions Of elderly patients with cN0 er+ breast cancer, 23% were pN+ on slnb. Size was the primary predictor of nodal status, and yet significant rates of nodal positivity were observed even in tumours preoperatively sized at 1 cm or less. The use of rt and systemic adjuvant therapies differed by nodal status, although the long-term oncologic implications require further investigation. Multidisciplinary input on a case-by-case basis should be considered before omission of slnb.


Author Biographies

A. Laws, Foothills Medical Centre, University of Calgary

Department of Surgery

R. Cheifetz, BC Cancer, University of British Columbia

Department of Surgery

R. Warburton, Providence Health Care, BC Cancer, University of British Columbia

Department of Surgery

C.E. McGahan, BC Cancer, University of British Columbia

Department of Population Oncology

J.S. Pao, University of British Columbia

Department of Surgery, Providence Health Care

U. Kuusk, University of British Columbia

Department of Surgery, Providence Health Care

C. Dingee, University of British Columbia

Department of Surgery, Providence Health Care

M.L. Quan, University of Calgary

Department of Surgery, Foothills Medical Centre

E. McKevitt, University of British Columbia

Department of Surgery, Providence Health Care

Published
2020-07-01
How to Cite
Laws, A., Cheifetz, R., Warburton, R., McGahan, C., Pao, J., Kuusk, U., Dingee, C., Quan, M., & McKevitt, E. (2020). Nodal staging affects adjuvant treatment choices in elderly patients with clinically node-negative, estrogen receptor–positive breast cancer. Current Oncology, 27(5). https://doi.org/10.3747/co.27.6515
Section
Surgical Oncology