[Histonet] Formalin Fixation - HER2 testing

Morken, Tim Timothy.Morken <@t> ucsfmedctr.org
Wed Oct 13 10:15:13 CDT 2010

Just a cautionary note about the article mentioned by Richard: The study only tested known 3+ samples.

Any validation of fixation time reduction or extension would need to test the process on the expected range of expressions

" Ibarra JA and Rogers LW:  Fixation time does not affect expression of HER2/neu.  Am J Clin Pathol 2010;134:594-596."

Tim Morken
Supervisor, Histology, IPOX
UCSF Medical Center
San Francisco, CA, USA

-----Original Message-----
From: histonet-bounces <@t> lists.utsouthwestern.edu [mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Richard Cartun
Sent: Wednesday, October 13, 2010 8:01 AM
To: Histonet
Cc: Hadi Yaziji; Richard Eisen, M.D.
Subject: [Histonet] Formalin Fixation - HER2 testing

Hopefully, ASCO and CAP will relax their fixation guidelines for HER2 testing in the near future to reflect that prolonged fixation in formalin has little, if any, affect on HER2 protein overexpression (my personal experience).  Another article (see below) just appeared in the October issue of the American Journal of Clinical Pathology that supports this observation.  Please keep in mind that making sure that the tissue doesn't dry out, minimizing the "cold" ischemic time to under 1 hour, and submitting "thin" (2-3 mm) sections for histological processing are probably more important than time in formalin.

Ibarra JA and Rogers LW:  Fixation time does not affect expression of HER2/neu.  Am J Clin Pathol 2010;134:594-596.


Richard W. Cartun, MS, PhD
Director, Histology & Immunopathology
Director, Biospecimen Collection Programs
Assistant Director, Anatomic Pathology
Hartford Hospital
80 Seymour Street
Hartford, CT  06102
(860) 545-1596 Office
(860) 545-2204 Fax

Histonet mailing list
Histonet <@t> lists.utsouthwestern.edu

More information about the Histonet mailing list