Hello everyone,
     In my lab we use Dako's c-erb-B2 antibody without an unmasking technique.
I have read that an unmasking technique should be utilized on archival tissue
because tissue fixed with NBF, although blocked in paraffin, will continue to
bind up the antigen sites.  All archival tissue we have tested is negative
until we use an umasking technique and then our results have been what our
doc's call "equivocal" (uncertain as an indication). That doesn't sound like
much of a difference, but to our doc's it is.
     The reason we don't use an unmasking method on current tissue samples is
because this is a protein already present in normal cells - meaning...to use a
retrieval method could produce false positives.
     One of my concerns with Dako's HercepTest kit is that they state a
retrieval method must be used.
     Secondly, information in the literature provided from Dako on this test
is contradictory to the way that they present how wonderful this test is. For
example, their own literature states:
  * "The actual correlation of the DAKO HercepTest to HERCEPTIN clinical
outcome has not been established."
  * "HercepTest is not intended to provide prognostic information to the
patient and physician and has not been validated for that purpose."
  *  Dako's literature states that there is a 79% concordance between results
from their HercepTest and the clinical trial assay used in the Herceptin
study.  Does that seem low to anyone else but me?
     Thirdly, the method to which Genetech is contacting the head lab doctors
and  enticing them with the "FDA approval" and then Dako comes in right behind
them offering the doc's  a brand spanking new Dako immunostainer for a free
trial period, that rreeaallllyyy concerns me.

     So, does anyone else have any information, concerns of their own or would
just like to tell me to be quiet already?  (A Dako rep has already told me
that I'm full of hot air).


Sue Kennedy HT, (ASCP) IHC
Aurora Health Care
Milwaukee, WI
Szbell@aol.com