I am helping our students with their HTL registry slides and I have two
questions:

1.  A section of liver in the paraffin block measures 1.0 x 0.9 cm;
however, the section on the slide measures 1.0 x 1.0 cm.  Is this O.K.? 
The requirement is for a section of liver 1.0 x 1.0 cm., but is this for
the "gross" section or the "microscopic" section?

2.  Is it O.K. to see extracellular PSA immunoreactivity in the section
of prostate?  After all, PSA is released from prostatic epithelial cells
and should be seen in extracellular locations (this is why we can
measure it in the serum); however, it does give the appearance of
non-specific staining.

I appreciate your comments on these two issues.  Thanks!

Richard Cartun