Would you recommend PMRT for stage IIA (pT1c pN1a) ER+/HER2- grade 2 IDC in an elderly patient with a single positive non-sentinel lymph node?  

This is a patient where given comorbidities you have multiple options. I will often offer these patients 15 fractions to the chest wall with consideration of SCV. It's well-tolerated.

Agree, no PMRT reasonable given patient age, lack of LVI, low Oncotype, pre-op US showing no abnormal axillary LAD, small G2 tumor, small LN met, and lack of ENE. That said, I don't think offering PMRT with hypofractionation as suggested above by @Chirag S. Shah is unreasonable (in fact, though this...

If the single node was found on the mastectomy specimen and there was no SLNB or formal dissection, you could round back to your pathologist to get a better idea of the location and surrounding tissue. If, in fact, it was in the tail of spence and surrounded by glandular tissue, this may be an intra...

So odd this case. If she had lumpectomy, cN0, she could be offered HT alone. Considering that, and her age with multiple comorbidities, I'd be comfortable if she opted for HT alone.