Semiquantitative assessment of c-erbB-2 (HER-2) status in cytology specimens and tissue sections from breast carcinoma.
OBJECTIVE
To determine whether various methods of fixation of surgical pathology specimens from breast carcinomas would influence the outcome of evaluation of the expression levels of c-erbB-2 (HER-2). For this, comparisons were made between (1) alcohol-fixed (95%) and air-dried smears from fresh surgical pathology specimens of breast carcinomas, and (2) formalin-fixed, paraffin-embedded tissue sections of the same specimens.


METHODS
Alcohol-fixed and air-dried smears or touch preparations were made from 30 fresh mastectomy/lumpectomy surgical pathology specimens from breast carcinomas. Immunohistochemistry was performed using the c-erbB-2 primary antibody against the extracellular domain of the c-erbB-2 gene product. Staining was simultaneously performed on formalin-fixed, paraffin-embedded tissue sections of the same specimens. A semiquantitative approach was used for evaluation of immunostaining by three independent investigators, and a consensus was reached.


RESULTS
A total of 30 cases were reviewed. Tissue positivity was determined for c-erbB-2 in: 73% of alcohol-fixed specimens (n = 13 [3+] and n = 9 [2+]), 67% of air-dried smears (n = 9 [+3] and n = 11 [+2]) and 47% (n = 8 [+3]) and n = 6 [+2]) of formalin-fixed, paraffin-embedded tissue specimens. All formalin-fixed tissue specimens that were determined to positively express c-erbB-2 were also found to be positive on the alcohol-fixed smears.


CONCLUSIONS
The incidence of c-erbB-2 expression in fresh cytologic material is significantly higher (P < .05) than in formalin-fixed, paraffin-embedded tissue. Alcohol-fixed smears demonstrate a slightly higher percentage of cell staining and stronger intensity of c-erbB-2 expression than the matched, air-dried smears. This is a sensitive and simple processing method that can be routinely applied in surgical pathology or fine needle aspiration biopsy specimens for the detection of c-erbB-2 (HER-2), with clinical implications.
Solomides
C C
CC
Department of Pathology, Anatomy and Cell Biology and the Cytopathology Laboratory, Jefferson Medical College, Thomas Jefferson University, Pennsylvania, USA.
Zimmerman
R
R
Bibbo
M
M
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000388:Air; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D000431:Ethanol; D005260:Female; D005404:Fixatives; D005557:Formaldehyde; D006801:Humans; D019044:Image Cytometry; D007124:Immunoenzyme Techniques; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D016707:Tissue Fixation / Q000379:methods*
D000431:Ethanol; D005404:Fixatives; D005557:Formaldehyde; D018719:Erb-b2 Receptor Tyrosine Kinases