In an analysis of clinical trials reported in a research letter in JAMA Oncology, Brooks et al found no differences in long-term outcomes with the use of axillary lymph node dissection (ALND) vs sentinel lymph node biopsy (SLNB)—usually paired with adjuvant radiotherapy—among patients with breast cancer with ypN-positive disease after receiving neoadjuvant chemotherapy.
Study Details
The analysis focused on pooled data from the NSABP B-405 and B-416 trials of neoadjuvant chemotherapy in patients with breast cancer. A total of 630 patients with cN-positive, ypN-positive disease after neoadjuvant chemotherapy were included in the analysis. Of these patients, 599 underwent ALND, and 31 underwent SLNB. Adjuvant radiotherapy was received by 532 patients (89%) in the ALND group and 29 (94%) in the SLNB group (P = .99); regional nodal irradiation was expressly received by 401 (67%) and 19 patients (61%), respectively (P = .43). No differences between groups were observed in terms of demographic or tumor characteristics; patients who underwent ALND were more likely to have mastectomy as breast-directed treatment (P = .002).
Key Findings
Median follow-up for all patients was 4.5 years (range = 0.5–7.1 years).
Among all patients, no significant differences were found between the ALND group and the SLNB group in the 5-year rates of locoregional recurrence (9% vs 12%, P = .79), distant metastasis (31% vs 26%, P = .75), any recurrence (33% vs 32%, P = .79), breast cancer–specific survival (78% vs 79%, P = .83), disease-free survival (66% vs 71%, P = .85), or overall survival (75% vs 79%, P = .57). There were no differences in the 5-year rates of these outcomes observed between 401 patients in the ALND group vs 19 patents in the SLNB group who expressly received regional nodal irradiation.
The investigators stated: “In this pooled analysis, we found that SLNB may have similar outcomes as ALND when most of the patients go on to receive radiotherapy. These hypothesis-generating results are some of the first of their kind.”
They noted that the findings support the need for the ongoing Alliance A011202 trial (ClinicalTrials.gov identifier NCT01901094) to “definitively answer the extent of axillary surgery and whether radiotherapy can control low-volume chemoresidual nodes in ypN-positive disease.”
Raymond B. Mailhot Vega, MD, MPH, of the Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, is the corresponding author of the JAMA Oncology article.
Disclosure: The study was supported by grants from the National Cancer Institute. For full disclosures of the study authors, visit jamanetwork.com.
