unclear mammo after treatment

My wife finished chemo and radiation in July and had her first mammo a week ago.  To our fear, she got a callback.  Apparently due to the surgery and treatment they want a second look.  The OBGYN told us also there is an unclear area in the same breast. What does an unclear area mean?  She couldn’t get an appt for 2 weeks so we are sitting here very anxious.  Anyone with a similar experience?

BTW she had a CT Scan in August which was normal.  Could something happen so soon after?

Appt is Friday and as the days get closer our anxiety rises.  Anyone who can relate is much appreciated