section C

Question 1

Key IHC biomarkers for breast cancer?

Answer 1

ER, PR, HER2, Ki-67, sometimes CEA.

Question 2

What does ER/PR positivity mean for breast cancer?

Answer 2

Tumor likely responds to hormone therapy (e.g., tamoxifen).

Question 3

What does HER2 positivity mean?

Answer 3

Eligible for HER2-targeted therapy (trastuzumab).

Question 4

What is Ki-67 in breast cancer?

Answer 4

Proliferation marker-high Ki-67 = more aggressive tumor.

Question 5

Main sample for breast cancer diagnosis?

Answer 5

Core needle biopsy for histology and IHC.

Question 6

What is the main histochemical stain for breast cancer?

Answer 6

H&E for structure; IHC for markers.

Question 7

What is the role of CEA in breast cancer?

Answer 7

Used for monitoring, not primary diagnosis.

Question 8

Key biomarkers for prostate cancer?

Answer 8

PSA (blood), PAP, AMACR, NKX3.1 (IHC).

Question 9

Main diagnostic test for prostate cancer?

Answer 9

PSA blood test, needle biopsy for histology/IHC.

Question 10

What does high PSA suggest?

Answer 10

Possible prostate cancer (but can be high in benign conditions too).

Question 11

What is AMACR?

Answer 11

IHC marker-positive in prostate cancer cells.

Question 12

Main histochemical stain for prostate cancer?

Answer 12

H&E for structure; IHC for PSA, AMACR.

Question 13

Key biomarkers for cervical cancer?

Answer 13

HPV DNA (molecular), p16 (IHC), Ki-67.

Question 14

Main diagnostic test for cervical cancer?

Answer 14

Pap smear (cytology), biopsy for histology/IHC.

Question 15

What does p16 positivity mean?

Answer 15

Surrogate marker for high-risk HPV infection.

Question 16

Main risk factor for cervical cancer?

Answer 16

Persistent infection with high-risk HPV.

Question 17

Key biomarkers for colon cancer?

Answer 17

CEA, KRAS, BRAF, MSI, CA19-9.

Question 18

What does MSI mean?

Answer 18

Microsatellite instability-predicts response to immunotherapy, may indicate Lynch syndrome.

Question 19

Main diagnostic test for colon cancer?

Answer 19

H&E for structure, IHC for CEA/MSI, colonoscopy biopsy.

Question 20

Key biomarkers for liver cancer?

Answer 20

AFP (blood), Glypican-3, HepPar-1 (IHC).

Question 21

Main sample for liver cancer?

Answer 21

Needle biopsy for histology/IHC, blood for AFP.

Question 22

Main risk factors for liver cancer?

Answer 22

Hepatitis B/C, alcohol, cirrhosis.

Question 23

Key biomarkers for lung cancer?

Answer 23

EGFR, ALK, PD-L1, TTF-1, Napsin A (IHC), CEA.

Question 24

Main sample for lung cancer?

Answer 24

Biopsy (bronchoscopy, CT-guided), cytology (sputum).

Question 25

Main risk factor for lung cancer?

Answer 25

Smoking.

Question 26

Key biomarkers for stomach cancer?

Answer 26

HER2 (IHC), CA72-4 (blood), CEA, E-cadherin (IHC).

Question 27

Main diagnostic test for stomach cancer?

Answer 27

H&E for structure, IHC for HER2/E-cadherin, endoscopic biopsy.

Question 28

HER2 is a biomarker for which cancers?

Answer 28

Breast and stomach (gastric).

Question 29

CEA is a marker for which cancers?

Answer 29

Colon, breast, lung, pancreas, stomach.

Question 30

What is the difference between histochemistry and IHC?

Answer 30

Histochemistry uses dyes (e.g., H&E, PAS); IHC uses antibodies (e.g., HER2, p16).

Question 31

Why use both H&E and IHC in cancer diagnosis?

Answer 31

H&E shows tissue structure; IHC identifies specific proteins for diagnosis/therapy.

Question 32

Most common sample types for cancer diagnosis?

Answer 32

Tissue biopsy, cytology (cells), blood for biomarkers.

Question 33

What is a tissue fold and how do you fix it?

Answer 33

Wrinkle in section-fix by flattening in water bath before mounting.

Question 34

What does overstaining look like and how to fix?

Answer 34

Tissue too dark, details lost-reduce staining time or dilute stain.

Question 35

How to recognize air bubbles on a slide?

Answer 35

Clear, round circles-re-mount section or ensure slides are clean.

Question 36

What is vimentin and when is it positive?

Answer 36

Marker for mesenchymal cells (stroma, sarcomas, EMT); positive in stroma and some tumors.

Question 37

What does E-cadherin loss indicate?

Answer 37

Suggests EMT-linked to invasion and metastasis.

Question 38

Why is EMT important for cancer prognosis?

Answer 38

Linked to metastasis, therapy resistance, poor prognosis.

Question 39

How does IHC guide therapy in GI/liver/lung/stomach cancers?

Answer 39

Identifies targetable markers (e.g., HER2, EGFR, PD-L1), distinguishes tumor type, predicts behavior.