Diagnosis of malignant lesions

Question 1

Specimen collection must be

Answer 1

adequate, representative, and properly preserved

Question 2

Sampling approaches are:

Answer 2

total excision, biopsy, fine needle aspiration, cytology smears

Question 3

Fixation methods

Answer 3

freezing, formaldehyde (paraffin), glutaraldehyde (e- microscope), refrigeration (molecular analysis)

Question 4

H&E stain

Answer 4

H: basic, blue, basophilic: nucleic acids, ribosomes
E: acidic, pink, eosinophilic: cytoplasm, proteins

Question 5

Yellow or brown on H&E stain?

Answer 5

intrinsic cellular pigments, melanin, etc

Question 6

PAS

Answer 6

stain basal laminae (good for malignant lesions)

Question 7

Silver stain

Answer 7

stain reticular fibers

Question 8

Clear structure on H&E?

Answer 8

hydrophobic structures - rich in fat (adipocytes, myelin, golgi)

Question 9

Oil red O stain

Answer 9

stain fats

Question 10

Fine-needle aspiration

Answer 10

aspirating cells and attendant fluid with a small bore needle –> cytological examination

Question 11

Papanicoloau stain is used

Answer 11

to demonstrate cells that have neoplastic characteristics

Question 12

Avidin-Biotin Conjugation ABC/DAB

Answer 12

specimen + incubation with primary Ab for suspected tumor antigen; incubation with secondary ant-IgG conjugate to biotin; + avidin = complexes with biotin (ABC-tissue) + DAB -> chromogen for brown coloring

Question 13

Use of ABC/DAB immunohistochemistry

Answer 13

identification of tumors that resemble each other

Question 14

Immunohistochemistry for intermediate filaments

Answer 14

for malignant tumor identification of origin, tumor cells contain intermediate filaments consistent with their origin

Question 15

Distinguishing class of leukemia and lymphoma

Answer 15

use of immunohistochemistry

Question 16

Immunohistochemistry for tissue-specific or organ-specific antigens

Answer 16

determines origin or metastatic tumor

Question 17

Tumor cells expressing cytokeratins

Answer 17

epithelial origin

Question 18

Tumor cells expressing desmin

Answer 18

muscle origin

Question 19

Immunohistochemistry can distinguish between subtypes of cancer (ER-positive, ER-negative, capthesin D) relies on

Answer 19

overexpression of proteins within the cells

Question 20

Importance of distinguishing subtypes in cancer

Answer 20

determining susceptibility to therapy

Question 21

ER-positive therapy

Answer 21

ER expression; responsive to tamoxifen

Question 22

Tamoxifen action

Answer 22

binds ER, cannot bind coactivators

Question 23

ER-negative therapy

Answer 23

no ER expression; responsive to Herceptin

Question 24

Herceptin action

Answer 24

cancer overexpresses ERBB-> HER2/neu protein; Herceptin binds and inactivates the cell surface GFR

Question 25

Cathepsin-D breast cancer

Answer 25

rapid development of metastases (metastatic potential)

Question 26

FC

Answer 26

gives information about physical and chemical structure of each cell

Question 27

FSC =

Answer 27

cell volume

Question 28

SSC =

Answer 28

shape of nucleus, cytoplasmic granule types, membrane roughness

Question 29

Fluorescence in FC

Answer 29

presence (relative quantity) or antigen on surface

Question 30

FC used to

Answer 30

classify leukemia and lymphoma, detection of ploidy

Question 31

aneuploidy is associated with

Answer 31

poorer prognosis for cancer patient

Question 32

Primary modality for cancer diagnosis

Answer 32

histology

Question 33

FISH

Answer 33

used to differentiate B and T cell malignancies, by detection of specific translocations that activate oncogenes

Question 34

FISH procedure

Answer 34

DNA probe for specific sequence + sample + fluorophores --> reveals translocations and other chromosomal rearrangements

Question 35

Array based comparative Hybridization

Answer 35

examine the molecular profile (quantify the expression of large numbers of genes) of different tumors using mRNA levels -> gives clues of potential over expression of tumor markers

Question 36

Array based comparative Hybridization complications

Answer 36

uses mRNA which do not directly correspond with proteins; this is due to rate of translation, protein breakdown, and protein export

Question 37

Complications of using tumor markers

Answer 37

low specificity/sensitivity, used as supporting evidence

Question 38

Carcinoembryonic antigen (CEA)

Answer 38

glycoprotein produced in embryonic tissues of the digestive tract, pancreas, and liver; may be elevated in colorectal and pancreatic carcinoma

Question 39

CEA tumor marker use

Answer 39

because it is also elevated in certain non-malignant disease, there is LOW specificity and sensitivity; but may be useful as a prognostic indicator (CEA increased with tumor size)

Question 40

Alpha fetal protein

Answer 40

glycoprotein produced early in fetal life by the yolk sac, liver, and GI tract; may be elevated in hepatocellular carcinoma and germ cells of the testis

Question 41

PSA

Answer 41

prostate specific membrane antigen used as a marker for prostate cancer

Question 42

HCG

Answer 42

testicular tumor marker

Question 43

CA125

Answer 43

tumor marker for ovarian tumors

Question 44

Main factors for prognosis and therapy

Answer 44

tumor size, metastases