Would you cover regional nodes in an early-stage breast cancer with a non-mapping sentinel lymph node?

Based on the SSO Choosing Wisely Guidelines (https://www.surgonc.org/wp-content/uploads/2020/11/SSO-5things-List_2020-Updates-11-2020.pdf) to not routinely use SLN biopsy in clinically node negative women ≥70 years of age with early stage hormone receptor positive, HER2 negative invasive breast cancer, I would be unlikely to cover the regional nodes in this patient, regardless of the fact that there was a non-mapping SLN. Furthermore, given the fact that Oncotype DX testing provides the 9-year d...

I would include levels 1 and 2 in the RT field if the patient opts for whole breast RT.

I'd cover the SCV.

Known risk factors:

Grade 3 disease

Medial tumor location

High Oncotype score, declining recommended chemotherapy

Despite age > 70, given good health/life expectancy, other risk factors including LVSI or luminal B disease would lead me to cover regional nodes including the IM chain and SCV fossa. I also don't think it would be unreasonable to consider without these additional risk factors but would at least include low axilla in the tangent as recommended by Dr. @Dr. First Last.

So we have a woman in her 70s with ER+ PR- HER2- stage 1a breast cancer who refuses chemotherapy and is considering RNI in addition to WBRT and endocrine therapy.

I don't believe one can show a survival advantage to RNI in this situation, although there was a meta-analysis done after PRIME II looking at the *omission* of radiation altogether in stage 1 grade III patients that showed a worsening of cause-specific survival.

Also, one can show the RNI will add a percent chance of radiation pneumon...