[Histonet] IHC Formalin vs frozen

[JColCLEFA <@t> aol.com]

My lab works like most clinical labs in that all tissue is submitted in 
fixative for H&E staining first. Once the pathologist sees the H&E sections he or 
she will determine whether special stains or Immunostains are required. We 
process about 100,000 surgical cases per year, and I do about 400 Immuno slides a 
day. It is much easier and more efficient to work with paraffin blocks rather 
than cut 400 frozen slides each day for our 5 hour TAT requirement.   I've 
worked with frozen and paraffin processed material extensively, (I also run our 
muscle biopsy lab) and as a muscle tech I assume you realize how labor 
intensive it would be to handle such a high volume of varied tissue (bone marrow 
biopsies, fatty and fibrous breast tissue, cytology specimens etc) in a frozen 
arena. We also recieve breast tissue and colon tumor tissue from other hospitals 
and from as far back at 1980 and the standard of care is formalin fixation and 
paraffin processing. We have done intensive comparison studies (frozen to 
fixed) and I can assure all my pathologists that   our staining reactions are 
optimal. In our high volume, low staffing (me and 1 other tech) situation, it's 
easier to keep as many procedures as similar as possible. Also, lastly, we cut 2 
micron sections for 40% of our slides and the distortion from freezing+ the 
thinness of section required eliminate the utility of frozen sectioning.