Clinical Question: Is sentinel lymph node biopsy preferred over standard axillary node dissection in patients undergoing surgery for breast cancer?

Setting: Inpatient (any location) with outpatient follow-up

Study Design: Randomized controlled trial (nonblinded)

Allocation: Concealed

Synopsis: In this multicenter study, women younger than 80 years scheduled to have a wide local excision or mastectomy for clinically node-negative invasive breast cancer were randomly assigned to standard axillary node dissection (n = 496) or sentinel lymph node biopsy (n = 495). Before being allowed to participate in the trial, the surgeons must have performed at least 40 sentinel lymph node biopsies that were followed by more invasive axillary node dissection. If the surgeon identified the sentinel lymph node at least 90 percent of the time, he or she could participate. The main outcomes—lymphedema and quality of life—were assessed via intention to treat.

At the end of one year, 2.1 percent of the standard treatment patients reported moderate to severe lymphedema compared with 0.8 percent of those treated with sentinel node biopsy (number needed to treat = 80). Participants undergoing sentinel node biopsy reported better quality of life, as measured by the Trial Outcome Index of the Functional Assessment of Cancer Therapy–Breast, a breast cancer–specific quality-of-life measure. At the end of one year, the researchers had complete follow-up data on 82 percent of the patients, which could affect the overall results.

Bottom Line: Compared with standard axillary node dissection, sentinel lymph node biopsy is associated with less lymphedema and better quality of life in patients undergoing surgery for early stage breast cancer that clinically appears to be node-negative. (Level of Evidence: 2b)