Diane, that's an annoying artifact, for sure.  I think it might be useful to record the case numbers of the biopsies that show the artifact, and see if there is any correlation to staffing in the GI suite that is doing these. If they all come from one room, or one physician...it's drying artifact happening before fixation.  Are they being grossed by one person/pathologist when you see the artifact, and by someone else when you don't?  It will take some detective work to find out if it is a personnel issue.

On the other hand, I have seen the same type of artifact on bone marrow samples that were most likely inadequately fixed prior to decalcification. Are these samples being grossed anywhere that they are subjected to decalcified samples (hence they may be coming in contact with a HCl-based decal solution before adequate fixation).  It's a stretch, but something else to muddy the waters, for sure.

We've also seen that artifact on placenta samples.  Again, my instinct tells me it's drying artifact that causes it.  I'd be willing to put a couple dollars on it.

If you are using heat on your processor during the alcohol dehydration and Clear-Rite steps, maybe lower the temp to 25 degrees and see if that helps?

Good luck, and I applaud your determination.

Teri Johnson
Stowers Institute for Medical Research
Kansas City, MO 64110