In a very young woman who is s/p mastectomy for a small, high grade, Her2 positive breast cancer, with a micromet in a sentinel node, would you favor completion axillary dissection or PMRT or close surveillance?

These are relatively common cases. The IBCSG 23-01 study does not support ALND in patients with micrometastases (Galimberti et al., PMID 30196031) though <10% underwent mastectomy so the majority of patients likely received RT to part of the axilla with whole-breast irradiation.

In patients presentin...

Micromets and mastectomy prospective and retrospective relatively large data available suggest regional recurrence rate is 0 to 5 percent without any additional regional treatment beyond SNLN in patients with t1 and t2 primary. I favor surveillance. The only time I consider treatment is triple-negat...

The short answer is I favor ALND for the additional staging information afforded by that procedure. I do not believe this patient’s risk of recurrence based on the available information (direct to surgery, small HER+ primary with micromet) is high enough to warrant the risks associated with comprehe...

To supplement the posts thus far, you may consider the following points in counseling the patient on probabilities of recurrence without RT:

- In the observation arm of IBCSG 23-01, n=425 received BCS and 18.8% had IORT alone (in that way, generally had no radiation hitting part of the axilla). While...

In HR+ and/or HER2+ disease, with good systemic therapy available, I do not feel strongly about PMRT for micromets, although will have a discussion about it. If the surgeon is considering ALND, then I think PMRT is a good alternative with less toxicity but neither is mandatory. I am more likely to r...