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QIHC 2 2026 QUESTIONS AND
ANSWERS| ACE YOUR GRADES.
Which of the following combinations would yield the best double-
stain?
DAB as chromogen with ER and new fuchsin as the chromogen
with PR
DAB as chromogen with kappa and new fuchsin as chromogen
with lambda
Fast red as chromogen with high molecular weight keratin and
new fuchsin as chromogen with pan keratin
Fast Blue as chromogen for CD3 and BCIP-NBT as chromogen
for CD20 - correct answer -DAB as chromogen with kappa and
new fuchsin as chromogen with lambda
Fixatives that tend to mask antigenic sites and hamper
immunohistochemical localization of antigens contain:
mercury
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phosphates
aldehydes
alcohol - correct answer -aldehydes
The peroxidase staining procedure in which reagents are linked
exclusively by antigen-antibody reactions without any conjugation
steps is:
avidin-biotin-peroxidase complex method
peroxidase-anti-peroxidase
indirect immunoperoxidase method
direct immunoperoxidase method - correct answer -peroxidase-
anti-peroxidase
A brain biopsy reveals a poorly differentiated malignant tumor.
The differential diagnosis is primary versus metastatic brain
cancer. The most useful antibody panel to resolve this differential
is:
cytokeratin, vimentin, muscle common actin
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S-100, cytokeratin AE1/3, synaptophysin
glial fibrillary acid protein, cytokeratin AE1/3, synaptophysin
carcinoembryonic antigen, leukocyte common antigen, S-100 -
correct answer -glial fibrillary acid protein, cytokeratin AE1/3,
synaptophysin
If your antibody is FDA approved but your protocol is different
how many tests do you need to run when validating?
10 previously known positive cases
20 positive and 20 negatives cases
10 negative cases
15 positive and 15 negative cases are run - correct answer -20
positive and 20 negatives cases
The step in the IHC stainings process that allows the exposure of
the sought after epitopes is called:
direct staining
QIHC 2 2026 QUESTIONS AND
ANSWERS| ACE YOUR GRADES.
Which of the following combinations would yield the best double-
stain?
DAB as chromogen with ER and new fuchsin as the chromogen
with PR
DAB as chromogen with kappa and new fuchsin as chromogen
with lambda
Fast red as chromogen with high molecular weight keratin and
new fuchsin as chromogen with pan keratin
Fast Blue as chromogen for CD3 and BCIP-NBT as chromogen
for CD20 - correct answer -DAB as chromogen with kappa and
new fuchsin as chromogen with lambda
Fixatives that tend to mask antigenic sites and hamper
immunohistochemical localization of antigens contain:
mercury
, Page | 2
phosphates
aldehydes
alcohol - correct answer -aldehydes
The peroxidase staining procedure in which reagents are linked
exclusively by antigen-antibody reactions without any conjugation
steps is:
avidin-biotin-peroxidase complex method
peroxidase-anti-peroxidase
indirect immunoperoxidase method
direct immunoperoxidase method - correct answer -peroxidase-
anti-peroxidase
A brain biopsy reveals a poorly differentiated malignant tumor.
The differential diagnosis is primary versus metastatic brain
cancer. The most useful antibody panel to resolve this differential
is:
cytokeratin, vimentin, muscle common actin
, Page | 3
S-100, cytokeratin AE1/3, synaptophysin
glial fibrillary acid protein, cytokeratin AE1/3, synaptophysin
carcinoembryonic antigen, leukocyte common antigen, S-100 -
correct answer -glial fibrillary acid protein, cytokeratin AE1/3,
synaptophysin
If your antibody is FDA approved but your protocol is different
how many tests do you need to run when validating?
10 previously known positive cases
20 positive and 20 negatives cases
10 negative cases
15 positive and 15 negative cases are run - correct answer -20
positive and 20 negatives cases
The step in the IHC stainings process that allows the exposure of
the sought after epitopes is called:
direct staining
