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Matthew Kurian: 2025 ASCO Guidelines on Sentinel Lymph Node Biopsy in early-stage breast cancer

Matthew Kurian/youtube.com

Apr 29, 2025, 03:52

Matthew Kurian: 2025 ASCO Guidelines on Sentinel Lymph Node Biopsy in early-stage breast cancer

Matthew Kurian, Assistant professor of medicine at the University of Kentucky College of Medicine, posted on LinkedIn:

“New 2025 American Society of Clinical Oncology (ASCO) Guidelines on Sentinel Lymph Node Biopsy (SLNB) in early-stage breast cancer have just been released — and they mark a major shift toward de-escalation of axillary surgery based on many studies (SOUND and INSEMA) that were discussed at San Antonio Breast Cancer Symposium 2024.

Key takeaways from the update (Park et al., Journal of Clinical Oncology):

Clinicians should not recommend routine SLNB for select patients who are:

Postmenopausal and ≥50 years

With grade 1–2, ≤2 cm, HR+/HER2- tumors

Clinically node-negative by axillary ultrasound

Undergoing breast-conserving therapy

Omission of ALND is reinforced in patients with 1–2 positive sentinel nodes undergoing breast-conserving surgery with radiation or mastectomy with regional nodal irradiation.

SLNB may still be offered in special circumstances: T3–T4c tumors, multicentric disease, DCIS treated with mastectomy, prior axillary surgery, obesity, male, or pregnancy.

This guidance pushes forward long-discussed shifts in axillary management—but it also surfaces some important questions:

Are we ready to skip SLNB at 50? Is that too young?

Are we moving too quickly in de-escalation without long-term data across diverse patient populations? Many of these studies are predominantly in Caucasian populations.

How will this play out across community vs academic settings—especially with multidisciplinary variation in comfort levels and the amount of breast radiologists within the community?

Partial Breast Irradiation (PBI) — A Question Mark

PBI targets only the tumor bed, not the whole breast or regional nodes. The guideline does not explicitly address SLNB omission in patients receiving PBI (SOUND and INSEMA the majority of patients received WBI), but this raises concern: If SLNB is omitted and PBI is used, there’s no treatment of undetected nodal disease. Current clinical trials (e.g., LUMINA, EXPERT) are still exploring whether omission of both SLNB and RNI is safe in ultra-low-risk patients.

Clinical Implication: If you’re omitting SLNB, you likely should not use PBI alone without very careful patient selection and multidisciplinary discussion.

As oncologists, we’re always trying to strike the right balance: less is more when it’s safe—but how sure are we, and for whom?

Full guideline here.”