Top Line: Who couldn’t use a refresher on de-escalation of axillary management for breast cancer?
The Study: This sweeping review revisits decades of axillary management, from the nihilistic elegance of the OG NSABP B-04 to the modern era of biologically-informed restraint. In cN0 disease, trials like SOUND and INSEMA show no difference in cancer control with omission of sentinel node sampling in carefully selected patients–read: older, hormone receptor-positive, HER2-negative, negative axillary US–with the expected perks—less lymphedema and pain. For those with occult pN1 disease, Z0011, AMAROS, and SENOMAC collectively cement sentinel node sampling with low axilla radiation as an equally-efficacious and lower morbidity alternative to completion axillary dissection. The plot thickens in cN+ disease: B51 suggests that both axillary dissection and even nodal irradiation may be safely omitted after pCR to neoadjuvant therapy, though longer follow-up is warranted to learn late recurrence patterns for hormone receptor-positive patients. Meanwhile, the upfront mastectomy crowd remains a gray zone—radiation omission is feasible in select low-risk pN1 patients post-axillary dissection, remembering that lymphedema outcomes favor omission of dissection over omission of post-mastectomy radiation and that omission of both is still investigational territory. Ultimately, figure 1 provides a print-worthy algorithm.
TBL: “As the shift towards axillary surgery de-escalation continues, multidisciplinary collaboration is critical, and radiation oncologists should account for surgical de-escalation when optimizing radiation treatment design.” | Mitchell, Pract Radiat Oncol 2026
The Study: This sweeping review revisits decades of axillary management, from the nihilistic elegance of the OG NSABP B-04 to the modern era of biologically-informed restraint. In cN0 disease, trials like SOUND and INSEMA show no difference in cancer control with omission of sentinel node sampling in carefully selected patients–read: older, hormone receptor-positive, HER2-negative, negative axillary US–with the expected perks—less lymphedema and pain. For those with occult pN1 disease, Z0011, AMAROS, and SENOMAC collectively cement sentinel node sampling with low axilla radiation as an equally-efficacious and lower morbidity alternative to completion axillary dissection. The plot thickens in cN+ disease: B51 suggests that both axillary dissection and even nodal irradiation may be safely omitted after pCR to neoadjuvant therapy, though longer follow-up is warranted to learn late recurrence patterns for hormone receptor-positive patients. Meanwhile, the upfront mastectomy crowd remains a gray zone—radiation omission is feasible in select low-risk pN1 patients post-axillary dissection, remembering that lymphedema outcomes favor omission of dissection over omission of post-mastectomy radiation and that omission of both is still investigational territory. Ultimately, figure 1 provides a print-worthy algorithm.
TBL: “As the shift towards axillary surgery de-escalation continues, multidisciplinary collaboration is critical, and radiation oncologists should account for surgical de-escalation when optimizing radiation treatment design.” | Mitchell, Pract Radiat Oncol 2026