[Histonet] Non Formalin fixatives

[Dawson, Glen]

All,

Non formalin fixatives are, in my opinion, a poor choice for almost any lab.

Unless your lab is completely self sufficient and would never need to send blocks out for testing or consult, you will run into many possible problems when you need testing that you do not perform yourself.  Since the vast majority of labs use formalin fixation, another fixation method will require not only different protocols for testing like IHC, but also would require a bank of known positive controls processed with the same non-formalin fixative.  

In other words, if you were to need an IHC stain from an outside lab, it is highly unlikely that they would have all the appropriate controls needed processed with the same non-formalin fixative that you are using.

Some FDA approved kits mandate formalin fixation for the kit to be valid.  I have a client that used a fixative that "made their H&E's and Trichromes absolutely beautiful" but when they needed my FDA approved HercepTest run on them, it was not possible specifically because of the fixation.  This persuaded them to switch over to formalin.

As histology professionals, it would benefit all of us if we used the same fixative.  Formalin, with all its faults, is our best bet for a "universal fixative" since it is in the vast majority of histo labs.

My opinion,

Glen Dawson  BS, HT & QIHC (ASCP)
IHC Manager
Milwaukee, WI