[Histonet] New CAP question ANP.22760

[Mark Tarango]

That's what I thought at first too.  It might be helpful to post this letter
that I got from the CAP about this.  I tried to argue with them, but this is
the answer I got.


Dear Mark,

Your questions were forwarded to me for response.



During the Audio-conference, the idea of comparing a previously stained
slide (that had used the “old” lot) to one stained with the new lot was
deemed acceptable, but not optimal. Doing a simultaneous staining using old
and new lots, better demonstrates the performance characteristics of the
reagent.  The reason parallel staining is considered best practice is that
all other variables, such as variations in the lot of detection reagent or
instrument function, are eliminated from consideration when the slides are
stained contemporaneously.



The antibody "getting weak over time" should not happen to a significant
degree if the antibody is used within its expiration date.  If the lab is
having this kind of trouble, it should look carefully at its storage
conditions.



Demonstrating acceptable performance of the new lot, before being place into
service, is *required* for all accredited laboratories.



To answer the last question, the key is to order the new reagent well before
you run out of the old lot so that the parallel stain can be performed
before the old lot is consumed. One multi-tissue slide control slide would
suffice to evaluate a primary antibody lot in most cases, which helps to
minimize the impact on the lab.



I hope that this information is helpful.  Thank you for your participation
in the Laboratory Accreditation Program.



Sincerely,



*Kathy Passarelli, MT(ASCP)SBB*

*Technical Specialist*

*Laboratory Accreditation Program*

*College** of American** Pathologists*

*Phone: 1-(800)-323-4040 ext 7486*

*e-mail:  **kpassar <@t> cap.org* <kpassar <@t> cap.org>



On Fri, Jun 18, 2010 at 10:47 AM, McMahon, Loralee A <
Loralee_Mcmahon <@t> urmc.rochester.edu> wrote:

> I think that CAP means that you need to save the slide that you ran from
> the previous lot and compare it to the slide that you have stained with the
> new lot number.  To see if they are sufficient diagnostic quality.  Not put
> both lot numbers on the machine at the same time and then compare the
> slides?   We run Dako machines and it would be tricky to put both numbers on
> the same machine.
>
> Although this is my interpretation.
>
> Loralee McMahon, HTL (ASCP)
> Immunohistochemistry Supervisor
> Strong Memorial Hospital
> Department of Surgical Pathology
> (585) 275-7210
> ________________________________________
> From: histonet-bounces <@t> lists.utsouthwestern.edu [
> histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Mike Pence [
> mpence <@t> grhs.net]
> Sent: Friday, June 18, 2010 12:41 PM
> To: Ellen Yee; Laurie Colbert
>  Cc: histonet <@t> lists.utsouthwestern.edu
> Subject: RE: [Histonet] New CAP question ANP.22760
>
> I don't think I can do this with the automated system we are currently
> using. Ventana. Does any other Ventana users know if you can do this in
> "parallel"
>
> Mike
> -----Original Message-----
> From: histonet-bounces <@t> lists.utsouthwestern.edu
> [mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Ellen
> Yee
> Sent: Thursday, June 17, 2010 7:21 PM
> To: Laurie Colbert
> Cc: histonet <@t> lists.utsouthwestern.edu
> Subject: RE: [Histonet] New CAP question ANP.22760
>
>
> Sorry, I should have included it.
>
> ANP.22760  Are new lots of antibody and detection system reagents tested
> in parallel with old lots?  (NOTE: New lots of primary antibody and
> detection system reagents must be compared to the previous lot using an
> appropriate panel of control tissues.)
>
> Ellen Yee
>      _____
>
>  From: Laurie Colbert [mailto:laurie.colbert <@t> huntingtonhospital.com]
> To: Ellen Yee [mailto:eyee <@t> dpmginc.com]
> Sent: Thu, 17 Jun 2010 08:47:38 -0700
> Subject: RE: [Histonet] New CAP question ANP.22760
>
> Can you give us the wording of that question/checklist item? Laurie
>
> -----Original Message-----
> From: histonet-bounces <@t> lists.utsouthwestern.edu
> [mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Ellen
> Yee
> Sent: Wednesday, June 16, 2010 10:10 PM
> To: histonet <@t> lists.utsouthwestern.edu
> Subject: [Histonet] New CAP question ANP.22760
>
> How are IHC labs complying with this question? What is considered an
> appropriate panel of control tissues? What do you stain to test your
> detection systems?
>
> Ellen Yee
>
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