[Histonet] fixation question

[ncosenza <@t> siumed.edu]

Hello Histonetters:

Our lab has a resident wanting to start a project involving drug effect on tumor
size.  Since he is wanting to compare tumor size at certain time points after
drug treatment (and do IHC staining intensity), he wonders how much affect
varying fixation times will have on the tissue.  We are not doing the
processing or embedding ourselves so we can't control for such variation.

Is this a legitimate concern? If one piece of tissue sits in fix 24 hours before
processing/embedding, will the morphology be drastically different than a second
piece that sits longer (or shorter) than 24 hours?

Is so, would fixing the tissue ourselves for a set time and then putting in some
sort of buffer or ethanol before we ship the tissue to the company who embeds it
make a difference? The resident is really trying to minimize swelling or excess
shrinkage of the tissue.

Thanks!