Would you consider post-mastectomy radiation in patient with a triple negative tumor pT2N0?

In borderline cases, I look at some of the retrospective data showing higher recurrence rates in patients with close margins, premenopausal status, higher grade and T2 tumors.

In the specific case in the OP, I would discuss the data from the Chinese randomized trial (green journal 2011) showing an OS benefit in early-stage TNBC treated with mastectomy, along with the Canadian registry study from the JCO 2011 showing better outcomes in this population when they received radiation in the post lumpectomy setting vs no xrt after mastectomy and would discuss pmrt with that patient

In a case of a de novo T2N0, 5 cm triple negative breast cancer, I would discuss the data available and explain that it could be considered but my recommendation would be no PMRT. However, I would explain that her risk of locoregional recurrence is likely higher than that seen with a T1-2N0 ER+ cancer. If younger, it potentially makes the risk even higher and its a risk vs. benefit discussion particularly with respect to toxicities including lymphedema, reconstruction, and cardiac if this is a left sided case.

If this was recurrent, it would depend on the interval from initial RT but it could be considered. RTOG 1014 looked at APBI following RT and it can be done. Would be great to have dosimetry, and i would not hypofractionate the whole b...