Axillary Management and Outcomes After Neoadjuvant Endocrine Therapy in the Randomized PELOPS Trial

Area of Science:

• Oncology
• Breast Cancer Research
• Clinical Trials

Background:

• Limited data exists on axillary surgical management after neoadjuvant endocrine therapy (NET) for breast cancer.
• This study reports nodal status, surgical procedures, and outcomes from the NCT02764541 trial (2016-2020).

Purpose of the Study:

• To evaluate nodal status and surgical outcomes in patients with hormone receptor-positive, HER2-negative breast cancer receiving NET ± palbociclib.
• To compare the efficacy of sentinel lymph node biopsy (SLNB) versus axillary dissection (ALND) in patients with pathologically node-positive (ypN+) disease.

Main Methods:

• 188 patients with ER+, HER2- breast cancer were randomized to NET ± palbociclib for 24 weeks.
• Axillary surgery (SLNB ± ALND) and nodal evaluation methods were not protocol-specified.
• Exploratory endpoints included ypN+ rates, local-regional recurrence-free interval (LRRFI), and breast cancer-specific survival (BCSS).

Main Results:

• The addition of palbociclib to NET did not significantly alter pathologic nodal outcomes.
• Among 108 ypN+ patients, 26 underwent SLNB and 82 underwent ALND.
• At median follow-up of 4.65 years, 3-year LRRFI and BCSS were similar for SLNB and ALND groups.

Conclusions:

• Palbociclib addition to NET does not impact pathologic nodal outcomes.
• For ypN+ disease, ALND offers no apparent benefit over SLNB regarding LRRFI or BCSS.