tricky feature of a box

[Ken Stone]

I am making a medical chart. I would like to make a small box over which
one can placed a patient ID label. I would like to outline just the four
corners of the box, rather then a line all around the perimeter of the
entire box. There would then be a small amount of text centered within
the box stating "place label here".

How can I make the box with outlining at just the four corners?

thanks
Ken