[Histonet] I'm BACK!!

[Bryan Szpunar]

Hi Sarah,

Here is the 2014 AP checklist question covering your question. Note the
part at the end about ER, PR, HER2 in case you are doing those. I can post
that as well if it's applicable.


ANP.22750 Antibody Validation Phase II

The laboratory has documented validation of new antibodies, prior to use in
patient diagnosis.


NOTE: The performance characteristics of each assay in the
immunohistochemistry laboratory

must be appropriately validated before being placed into clinical use. The
initial goal is to establish

the optimal antibody titration, detection system, and antigen retrieval
protocol. Once optimized, a

panel of tissues must be tested to determine the assay's sensitivity and
specificity. The scope of

the validation is at the discretion of the laboratory director and will
vary with the antibody. For a

well-characterized antibody with a limited spectrum of antigenic targets,
like chromogranin or prostate

specific antigen, the validation can be limited. A panel of 10 positive and
10 negative neoplasms

would be sufficient in this setting. For an antibody that is not well
characterized and/or has a wide

range of reported reactivity, a more extensive validation is necessary. The
number of tissues tested

should, in this circumstance, be large enough to determine whether the
staining profile matches

that previously described.

An exception to the above requirements is that studies may not be feasible
for antigens such as

ALK that are only seen in rare tumors.

This checklist has additional validation requirements for HER2 and
estrogen/progesterone receptor

testing in breast carcinoma. Please refer to the subsection "Predictive
Markers," below.


Evidence of Compliance:

✓ Written procedure for the evaluation/validation of new antibodies


Hope that helps!


Bryan Szpunar, HT(ASCP)

Histology Lead

LabCorp Indianapolis

7750 Zionsville Road

Indianapolis, IN 46268