How would you manage a positive deep margin in the setting of mastectomy and expander placement?  

With these cases, I first discuss with the patient's surgeon if there is any role for re-excision. If not, then I look at whether it is prepectoral or subpectroal. With a subpectoral implant/expander, the at risk margin is in front of the implant/expander; while with a prepectoral implant/expander,...