Omission of Axillary Surgery May Lower Risks of Patient Morbidity without Reducing Survival in Low-Risk Breast Cancers

Reimer T, Stachs A, Veselinovic K, et al. Axillary Surgery in Breast Cancer—Primary Results of the INSEMA Trial. N Engl J Med. 2024.

Morrow M. Sentinel-Lymph-Node Biopsy in Early-Stage Breast Cancer—Is It Obsolete? N Engl J Med. 2024: in press.

Reimer and coauthors reported data from a randomized, prospective, non-inferiority study that compared survival outcomes in patients with low-risk breast cancers (tumor size <5 cm and clinically negative axilla examination by ultrasound imaging) who underwent sentinel lymph node biopsy or had axillary surgery omitted.

Patients (n = 5,502) were randomized in a 1:4 ratio. The main outcome of interest was occurrence or recurrence of cancer or death from any cause.

The analysis showed that omission of axillary surgery was non-inferior to use of sentinel lymph node biopsy at a mean follow-up of 6 years. Patients who did not undergo axillary surgery had significantly lower risk of lymphedema, impaired arm mobility, and shoulder pain.

In the editorial that accompanied the article, Morrow noted that omission of axillary surgery would reduce patient morbidity due to lymphedema, and so on, but lack of histologic findings from sentinel lymph node biopsy could negatively affect judgments regarding use of radiation therapy and adjuvant endocrine and chemotherapy in higher risk patients. Decisions to omit axillary surgery will need to be made after careful risk assessment and patient counselling.