Trends of Axillary Treatment in Sentinel Node-Positive Breast Cancer Patients Undergoing Mastectomy

Abstract

Background The ACOSOG-Z0011- and the AMAROS-trial obviated the need for axillary surgery in most sentinel node-positive (SLN+) breast cancer patients undergoing breast-conserving surgery (BCS). Data for patients who undergo mastectomy is scarce. The purpose of this study was to investigate patterns of axillary treatment in SLN+ patients treated by mastectomy in the years after the publication of landmark studies regarding axillary treatment in SLN+ breast cancer patients undergoing BCS. Methods This was a population-based study in cT1-3N0M0 breast cancer patients treated by mastectomy and staged as SLN+ between 2009 and 2018. The performance of an axillary lymph node dissection (ALND) and/or administration of postmastectomy radiotherapy (PMRT) were primary outcomes and were studied over time. Results The study included 10,633 patients. The frequency of ALND performance decreased from 78% in 2009 to 10% in 2018, whereas PMRT increased from 4 to 49% (P < 0.001). In ≥N1a patients, ALND performance decreased from 93 to 20%, whereas PMRT increased to 70% (P < 0.001). In N1mi and N0itc patients, ALND was abandoned during the study period, whereas PMRT increased to 38% and 13% respectively (P < 0.001), respectively. Age, tumor subtype, N-stage, and hospital type affected the likelihood that patients underwent ALND. Conclusions In this study in SLN+ breast cancer patients undergoing mastectomy, use of ALND decreased drastically over time. By the end of 2018 most ≥N1a patients received PMRT as the only adjuvant axillary treatment, whereas the majority of N1mi and N0itc patients received no additional treatment.

Retrospective Observational Study to Determine the Epidemiology and Treatment Patterns of Patients with Triple-Negative Breast Cancer

“…We observed a low rate of breast re-operations and/or ALND performed among patients who underwent breast-conserving surgery (BCS) with the SLNB and this supports a less radical approach. This is in line with current trends where several randomised clinical trials provided evidence of no benefits from ALND in those undergoing SLNB [42].…”

Characteristics and risk factors of axillary lymph node metastasis of microinvasive breast cancer

“…Before the results of the Z0011 trial had been published, ALND was the standard of care for patients with positive SLNB [22]. However, after the Z0011 trial had proven non-inferiority of 10-year overall survival of SLNB alone over ALND in patients with a clinical T1 or T2 stage with one or two positive SLNs, the number of routine ALND procedures displayed a decreasing trend [23,24]. Likewise, performing SLNB for patients with invasive breast cancer was the standard of care, but in trends of de-escalating axillary surgery, performing routine SLNB in clinically node-negative, early breast cancer is debatable.…”