Comparative analysis of three- and two-antibody cocktails to AMACR and basal cell markers for the immunohistochemical diagnosis of prostate carcinoma.
BACKGROUND
Immunohistochemistry using antibody cocktails against basal cell specific and cancer-associated markers is important in the diagnosis of prostate carcinoma in needle biopsies. We compared the usefulness for detecting prostate carcinoma of a three-marker cocktail of antibodies to α-methylacyl-CoA racemase (AMACR), p63 and cytokeratin (CK) 5 with a traditional two-marker cocktail of AMACR and p63.


METHODS
Sixty-six prostate needle biopsies were analysed prospectively. Serial sections were immunostained with the two- and three- antibody cocktails. Blinded slides were assessed individually by two pathologists and sensitivity, specificity and kappa statistics were calculated.


RESULTS
Both antibody cocktails contributed to the detection of prostate carcinoma in needle biopsies. There was an acceptable level of agreement between the pathologists for both the cocktails. Sensitivity was similar for one pathologist comparing both the cocktails (76.4% and 75.7%), but was slightly lower comparing the three-antibody with the two-antibody cocktail for the other pathologist (66.6% vs. 77.4%, respectively). Higher specificity values of 90.3% were achieved by both pathologists using three-antibody as compared with two-antibody cocktails (68.7% and 71.8%).


CONCLUSIONS
Antibody cocktails are important in diagnosing prostate carcinoma in needle biopsies. Adding an extra basal cell marker to the traditional two-antibody cocktail improves the specificity of detecting prostate carcinoma in limited needle biopsy material, and should be considered for routine diagnostic use.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2492231327330327.
Institute of Pathology, Aarhus University Hospital, Noerrebrogade 44, DK-8000, Aarhus C, Denmark. paradabi@rm.dk
Parag Deepak
PD
Dabir
Peter
P
Ottosen
Søren
S
Høyer
Stephen
S
Hamilton-Dutoit
D000911:Antibodies, Monoclonal; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D053555:Keratin-5 / Q000032:analysis; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D019998:Racemases and Epimerases / Q000032:analysis; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; C081876:CKAP4 protein, human; D053555:Keratin-5; D008565:Membrane Proteins; D019998:Racemases and Epimerases; C108352:alpha-methylacyl-CoA racemase