[Histonet] RE: Histonet Digest, Vol 77, Issue 36

[Troutman, Kenneth A]

Hello,

We do a two stage validation procedure here.  First, I will work up an antibody to get a working protocol.  I give the best slides along with a form recording the processes used for each slide (dilution, antigen retrieval solution, A-R time, chromogen, antibody incubation time, etc.) and I make the pathologist sign off on the one they like the best.  Next, we pull a number of cases (we do 10-15) that include known positives and negatives.  (If you are switching platforms, just pull the old slides and compare them to the new method.)   Record this data (block numbers, etc.) along with the pathologist's signature.  If it is a new antibody, I have to tell the pathologist to find a minimum of 10 cases that the stain will be used on and I can validate it that way.

If you are validating ER, PR and/or Her-2, you are in for a lot more work.  ASCO/CAP recommends 20 to 100 cases that must be compared to a known method.  ie someone else's lab or your old method.  We did 50 and it took awhile.

Sorry this is a bit choppy.  Feel free to email me with any other specific questions that you might have or if you want the forms I use.  We are in the same boat!  CAP is due any day, now!

Ashley Troutman BS, HT(ASCP) QIHC
Vanderbilt University Histopathology
1301 Medical Center Drive TVC 4532
Nashville, TN  37232
615-343-9134

Message: 7
Date: Wed, 28 Apr 2010 12:30:44 -0400
From: thisisann <@t> aol.com
Subject: [Histonet] IHC Validation Procedure
To: histonet <@t> lists.utsouthwestern.edu
Message-ID: <8CCB50748D97178-1C98-92FF <@t> webmail-d051.sysops.aol.com>
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Can anyone share their IHC Validation procedure.  I am preparing for a CAP inspection and want to make sure that the procedure I (presently do/may change to) is acceptable.  Thank you very much!