Chapter 3 ( Principles Of Neoplasia )

Question 1

Clonality can be determined by what ?

Answer 1

G6PD isoforms

Androgen receptor isoforms

Question 2

Clonality of B lymphocytes determined by what ?

Answer 2

Immunoglobulin light chain phenotype

Question 3

Kappa : lambda light chain ratio in normal and neoplasia ?

Answer 3

Norma 3 : 1

Neoplasia > 6 : 1 or < 1 : 3

Question 4

Which cell in the body no benign tumor is derived from it ?

Answer 4

Lymphocytes ( only malignant )

Question 5

How many devisions usually occur before clinical symptoms arise from cancer ?

Answer 5

30

Question 6

Aflatoxins ?

Answer 6

Hepatocellular carcinoma

Derived from aspergillus which can contaminate rice and grains

Question 7

Alkylating agents ?

Answer 7

Leukemia / Lymphoma

Side effect of chemotherapy

Question 8

Alcohol ?

Answer 8

Squamous cell carcinoma of oropharynx and upper esophagus
Hepatocellular carcinoma
Pancreatic carcinoma

Question 9

Arsenic

Answer 9

Squamous cell carcinoma of skin , Lung cancer , angiosarcoma of the liver
Present in cigarette smoke

Question 10

Asbestos ?

Answer 10

Lung carcinoma and methothelioma

Lung carcinoma is much more likely to occur

Question 11

Cigarette smoke ?

Answer 11

Carcinoma of oropharynx , esophagus , lung , kidney , bladder and pancreas
Polycyclic hydrocarbons are particularly carcinogens

Question 12

Nitrosamines ?

Answer 12

Stomach carcinoma

Found in smoked food ( high risk in japan )

Question 13

Nephthylamine ?

Answer 13

Urothelial carcinoma of bladder

Derived from cigarette smoke

Question 14

Vinyl chloride

Answer 14

Angiosarcoma of the liver

Occupational exposure , used to make PVC for use in pipes

Question 15

Nickel , chromium , beryllium or silica ?

Answer 15

Lung carcinoma

Occupational exposure

Question 16

Oncogenic viruses and their cancers ?

Answer 16

1- EBV : nasopharyngeal carcinoma , burkitt lymphoma , CNS lymphoma in AIDS

2- HHV-8 : kaposi sarcoma

3- HBV , HCV : hepatocellular carcinoma

4- HTLV-1 : adult T cell leukemia / lymphoma

5- HPV ( 16,18,31,33) : squamous cell carcinoma of vulva, vagina, anus, cervix and adenocarcinoma of cervix

Question 17

Ionizing radiation ?

Answer 17

AML
CML
Papillary carcinoma of the thyroid
Generates hydroxyl free radicles

Question 18

Nonionizing radiation ?

Answer 18

BCC of skin
SCC of skin
Melanoma of skin
Results in formation of pyrimidine dimers in DNA

Question 19

Categories of oncogenes ?

Answer 19

1- Growth factors 
2- Growth factor receptors 
3- Signal transducers 
4- Nuclear regulators
5- cell cycle regulators

Question 20

Mechanism of mutated ras causing cancers ?

Answer 20

Inhibits the activity of GTPase activating protein , this prolongs the activated state of ras resulting in increased growth signals

Question 21

PDGFB ?

Answer 21

Platelet derived growth factor
Overexpression / autocrine loop
Astrocytoma

Question 22

ERBB-2 / HER2-neu ?

Answer 22

Epidermal growth factor receptor
Amplification
Subset of breast carcinoma
Ttt : Transtuzamab ( Herceptin )

Question 23

RET ?

Answer 23

Neural growth factor receptor
Point mutation
MEN 2A , MEN 2B , sporadic medullary carcinoma of thyroid

Question 24

KIT ?

Answer 24

Stem cell growth factor receptor
Point mutation
Gastrointestinal stroma tumor

Question 25

RAS gene family ?

Answer 25

GTP binding protein Point mutation Carcinomas , melanoma , lymphoma

Question 26

ABL ?

Answer 26

Tyrosine kinase t(9;22) with BCR CML and some types of ALL (Ph + )

Question 27

c-MYC ?

Answer 27

Transcription factor t(8;14) involving IgH Burkitt lymphoma

Question 28

N-MYC ?

Answer 28

Transcription factor Amplification Neuroblastoma

Question 29

L-MYC ?

Answer 29

Transcription factor Amplification Lung carcinoma ( small cell )

Question 30

Cyclin D1 ?

Answer 30

Cyclin t(11;14) involving IgH Mantel cell lymphoma

Question 31

CDK4 ?

Answer 31

Cyclin dependent kinase Amplification Melanoma

Question 32

Mechanism of Rb mutation in causing retinoblastoma ?

Answer 32

Results in constitutively free E2F allowing progression through the cell cycle and uncontrolled growth of cells

Question 33

Defect in Follicular lymphoma ?

Answer 33

t(14;18) moves Bcl2 gene to the Ig heavy chain locus on chromosome 14 resulting in increased Bcl2 —> mitochondrial membrane is further stabilized prohibiting apoptosis

Question 34

Sequence of tumor invasion and spread ?

Answer 34

Down regulation of E-cadherin —> dissociation of attached cells —> cells attach to laminin —> destroy basement membrane by Collagenase —> cells attach to fibronectin and spread locally —> entrance into vascular or lyphatic spaces for distant spread

Question 35

Carcinomas that exhibit hematogenous spread ?

Answer 35

1- renal cell carcinoma 2- hepatocellular carcinoma 3- follicular carcinoma of the thyroid 4- choriocarcinoma

Question 36

Keratin histochemical stain for ?

Answer 36

Epithelium

Question 37

Vimentin histochemical stain for ?

Answer 37

Mesenchyme

Question 38

Desmin histochemical stain for ?

Answer 38

Muscle

Question 39

GFAP histochemical stain for ?

Answer 39

Neuroglia

Question 40

Neurofilament histochemical stain for ?

Answer 40

Neurons

Question 41

Chromogranin histochemical stain for ?

Answer 41

Neuroendocrine cells ( small cell carcinoma of lung and carcinoid tumors )

Question 42

S-100 histochemical stain for ?

Answer 42

Melanoma Schwannoma Langerhans cell histiocytes