Histopathology 1

Question 1

The standard slide

Answer 1

Routine is on formalin fixed, paraffin embedded tissue

Stained with haematoxylin and eosin

Examined by light microscopy

Most diagnostic practice on a microscope

Possible to scan sections and view on a remote web viewer

Question 2

Special stains

Answer 2

Diastase periodic acid schiff for mucin

EVG for elastin, fibrosis

Masson fontana for melanin

Perl’s for iron

Von kossa for calcium

Ziehl neelsen for AFB

Giemsa for HP

Question 3

Cytological changes in neoplasia

Answer 3

Increased N:C ratio

Irregular nuclear margin

Irregular distribution and texture of chromatin

Question 4

Immunohistochemistry

Answer 4

Identifies specific proteins in tissue by using monoclonal antibodies

Important and useful in developing a differential diagnosis

Also gives prognostic information and informs treatment

Question 5

The six tissues of origin

Answer 5

Epithelial (endothelial, synovial, mesothelial, meningeal)

Mesenchymal (fat, bone, cartilage, fibrous tissue, vessels)

Muscle

Neural (also melanocytes)

Germ line cells

Haematopoietic, lymphoid, blood

Question 6

Epithelial markers

Answer 6

Cytokeratins

CK MNF 116

AE1/3

BerEP4

MOC-31

EMA

Question 7

Mesothelial markers

Answer 7

Cytokeratins 5/6

HBME

Calretinin

Question 8

Melanocytic markers

Answer 8

S100

MelanA

HMB45

Panmelanoma

Question 9

Neuroendocrine markers

Answer 9

Chromogranin

CD56

Question 10

Glial markers

Answer 10

GFAP

Question 11

Mesenchymal markers

Answer 11

Vimentin

Desmin

Actin

Question 12

Lymphoid markers

Answer 12

CD45

CD3

CD20

Question 13

Vascular markers

Answer 13

CD31

Question 14

Cytokeratins

Answer 14

The intermediate filaments of epithelial cells

Different expressed in different epithelia

Question 15

CK7 positive CK20 positive carcinomas

Answer 15

Upper GI (adenocarcinoma)

Pancreatic (ductal)

Urothelial

Question 16

CK 7 positive CK20 negative carcinomas

Answer 16

Breast

Ovarian

Pulmonary (adenoca)

Endometrial

Thyroid

Question 17

CK7 negative CK20 positive carcinomas

Answer 17

Colorectal

Merkel cell

Question 18

CK7 negative CK20 negative carcinomas

Answer 18

Prostatic

Hepatocellular

Renal cell

Adrenal cortical

Question 19

Grading of neoplasms

Answer 19

Well differentiated (G1)
Moderately differentiated (G2)
Poorly differentiated (G3)

Increasingly
High grade
Low grade

Question 20

Staging of neoplasms

Answer 20

How far the tumour has spread

TNM
FIGO (gynaecological)
AJCC (melanoma)
ENET (neuroendocrine)

Question 21

Prognostic biomarkers

Answer 21

Breast BRCA1

Ovary BRCA1

Breast Her-2/ neu (worse)

Colon high frequency MSI (better)

NSCLC K-ras (worse)

NSCLC EGFR (worse)

Question 22

Predictive biomarkers

Answer 22

RCC CAIX (response to IL-2)

KIT GIST (response to imatinib)

NSCLC EGFR (response to gefitinib)

Breast ER (response to tamoxifen)

Breast Her-2 (response to trastuzumab)

Gastric Her-2 (response to multiagent therapy)

NSCLC K-ras (less response to EGFR)

CRC K-ras (less response to EGFR)

NSCLC p53 (response to cisplatin)

Breast PTEN (reduced effectiveness to trastuzamib)

Lymphoma CD20 (response to anti CD20)