CHICAGO – Sentinel lymph node dissection without axillary lymph node dissection offers excellent regional control in select patients with early metastatic breast cancer who are treated using breast-conserving therapy and adjuvant systemic therapy, according to 10-year results from the American College of Surgeons Oncology Group (ACOSOG) Z0011 Randomized Trial. ACOSOG is now part of Alliance for Clinical Trials in Oncology.
The findings confirm the previously reported 5-year outcomes, which demonstrated no significant difference in locoregional recurrence for patients with positive sentinel nodes who were randomized to undergo axillary lymph node dissection (ALND) or no further axillary treatment, Dr. Armando E. Giuliano of Cedars-Sinai Medical Center, Los Angeles, reported at the annual meeting of the American Surgical Association.
“In fact, the [5-year] results were highly significant showing noninferiority of sentinel lymph node dissection,” he said.
At a median follow-up of 9.25 years, there still was no statistically significant difference between 446 sentinel lymph node dissection (SLND)–only patients and 445 completion ALND patients with respect to the rate of locoregional recurrence, Dr. Giuliano said.
“The 10-year locoregional recurrence incidence after axillary lymph node dissection is 6.2%, compared to 5.3% after sentinel lymph node dissection alone,” he said, noting that most recurrences were seen in the first 5 years.
Of the ALND patients, 27% had additional positive nodes removed beyond the sentinel nodes.
“Therefore, about 27% of patients who underwent sentinel node dissection alone had residual disease remaining in the axilla undissected. Despite this high possibility of residual disease, very few regional recurrences were seen in either arm,” he noted.
Local recurrences occurred in 19 (5.6%) of patients in the ALND group and 12 (3.8%) in the SLND group, and regional recurrence was seen in 2 (0.5%) patients in the ALND group and 5 (1.5%) in the SLND group. The differences were not statistically significant.
Only hormone receptor status, Bloom-Richardson score, and tumor size were associated with locoregional recurrence. Omission of radiation increased local but not regional recurrence, but numbers were too few to draw further conclusions, he said.
“We can conclude, however, that sentinel lymph node dissection provides excellent locoregional control comparable to completion axillary lymph node dissection in these selected patients,” he said.
ACOSOG Z0011 subjects were patients with hematoxylin-eosin (H&E)–detected sentinel lymph node metastases undergoing breast-conserving therapy. The groups randomized to undergo ALND or to receive no further axillary treatment were similar with respect to age, Bloom-Richardson score, estrogen-receptor status, adjuvant systemic therapy, histology, and tumor size.
Nearly all patients had adjuvant systemic therapy (96% and 97% in the ALND and SLND groups, respectively), and about 60% in each group received chemotherapy.
Dr. Giuliano concluded that, despite the potential for residual axillary disease after SLND, SLND without ALND offers excellent regional control for selected patients with early metastatic breast cancer treated with breast-conserving therapy and adjuvant systemic therapy.
“Axillary lymph node dissection is not necessary for patients with early metastatic breast cancer and should be abandoned,” he said.
Dr. Giuliano had no disclosures.
The complete manuscript of this presentation is anticipated to be published in the Annals of Surgery pending editorial review