Path: Epidemiology of Cancer

Question 1

The incidence of cancer varies with all of the following except:
age, sex, race, comorbidities, geography, genetic background,

Answer 1

comorbidities

Question 2

Why is geographic variation in cancer incidence a risk factor?

Answer 2

thought to stem from different environmental exposures

Question 3

Cancers are most common in adults over age ___.

Answer 3

60

Question 4

Important environmental factors implicated in carcinogenesis include …?

Answer 4

infectious agents, smoking, alcohol, diet, obesity, reproductive history, and carcinogens

Question 5

There are 2 conditions related to tissue injury and the immune system that increase the risk of cancer. What are they?

Answer 5

chronic inflammation; immunodeficiency

Question 6

____ cancer is much more fatal than prostate or breast cancer.

Answer 6

Lung

Question 7

Why are most brain tumors in children benign yet fatal?

Answer 7

Most of the brain tumors in children are technically “benign”, but they tend to be fatal because they cannot be surgically removed, often do not respond to non-surgical therapies, and their autonomous growth in the unexpandable space of the skull compresses vital brain structures.

Question 8

About 60% of childhood cancer deaths are due to ____ ____ and ____ ____.

Answer 8

acute leukemias; brain tumors

Question 9

Acquired conditions that predispose to cancer can be divided into 3 categories. Please name them.

Answer 9

1. chronic inflammations
2. precursor lesions
3. immunodeficiency states

Question 10

Chronic inflammatory disorders and precursor lesions include many conditions that are all associated with ____ ____ ____. What is the significance of this?

Answer 10

increased cellular replication; this state creates a “fertile” soil for development of malignant tumors because of the repeated rounds of cell replication

Question 11

Immunodeficiency states predispose to what kind of cancers?

Answer 11

virus-induced

Question 12

Precursor lesions can be defined as …?

Answer 12

localized morphologic changes that are associated with a high risk of cancer

Question 13

The majority of tumor arising in the context of chronic inflammation are what kind of tumor?

Answer 13

carcinoma

Question 14

Virtually all precursor lesions arise in what tissue and are associated with increased risk of what type of cancer?

Answer 14

epithelial tissue; carcinoma

Question 15

How/why are pap smears useful?

Answer 15

they can detect dysplasia (precursor lesion) of the cervical endometrium before it becomes cancer

Question 16

What is dysplasia?

Answer 16

disordered growth; cellular atypia and messed up architecture; not [yet] cancer

Question 17

Normal uterine epithelium will have what histological features?

Answer 17

single basal cell layer; the higher cells and their nuclei are flatter than the basal cells; abundant glycogen in cytoplasm (appearing as clear cytoplasm)

Question 18

When basaloid cells are located here in the cervix, the worse the dysplasia. Where is “here”?

Answer 18

“here” is higher in the epithelium

Question 19

True or false: severe dysplasia looks pretty much the same as earl neoplasia, therefore can also be classified as carcinoma in situ.

Answer 19

False - severe dysplasia looks

pretty much the same as early neoplasia (carcinoma in situ), but is NOT cancer (yet)

Question 20

What is CIN?

Answer 20

cervical intraepithelial neoplasia; the term for all dysplasia and carcinoma in situ seen in cerival epithelium

Question 21

What is SIL?

Answer 21

squamous intraepithelial lesion, refers to cerival epithelium

Question 22

Which leads to cancer: chronic inflammatory diseases infectious or non-infectious etiologies?

Answer 22

trick question - either etiology can lead to cancer

Question 23

How does chronic inflammation lead to cancer? (3 areas of increased risk)

Answer 23

• increased cell proliferation to repair the tissue damage
• increase in the number of tissue stem cells - susceptible to mutation/transformation
• activated immune cells produce ROS that are directly genotoxic

Question 24

What are 4 important examples of chronic inflammatory conditions that lead to cancer?

Answer 24

1. inflammatory bowel disease, esp. ulcerative colitis –> carcinoma of colon
2. chronic hepatitis, especially chronic hepatitis C –> hepatocellular carcinoma
3. chronic pancreatitis –> pancreatic carcinoma
4. chronic cholecystitis –> gallbladder carcinoma

Question 25

Chronic epithelial injury often leads to metaplasia, which is what?

Answer 25

the replacement of one cell type with a second that is better able to survive the ongoing insult

Question 26

What is helicobacter pylori gastritis and how does it lead to cancer?

Answer 26

infectious Gram-negative bacterium that injects its CagA, activates cell proliferation pathways, causes degradation of p53; epithelial cells are irritated by this and undergo metaplasia, a precursor to gastric adenocarcinoma

Question 27

True or false: precursor lesions inevitably progress to cancer.

Answer 27

False - but they are associated with increased cancer risk

Question 28

What are 3 examples of precursor lesions in the setting of chronic inflammation,a nd can be recognized by the presence of metaplasia?

Answer 28

1. Barrett esophagus - due to GERD
2. Squamous metaplasia of bronchial mucosa - due to smoking
3. Intestinal metaplasia of the stomach - due to chronic gastritis

Question 29

What is non-inflammatory hyperplasia?

Answer 29

hyperplasia caused by something other than chronic inflammation; ex: endometrial hyperplasia is caused by sustained strogenic stimulation of the endometrium

Question 30

Non-inflammatory hyperplasia can potentially progress to what type of cancer?

Answer 30

endometrial carcinoma

Question 31

Another group of precursor lesions is ____ ____ that are at risk for malignant transformation.

Answer 31

benign neoplasms - but be aware that MOST benign neoplasms won’t undergo malignant transformation

Question 32

Benign tumors are at high risk for malignant transformation because they possess ____ ____.

Answer 32

genomic instability

Question 33

What is leukoplakia?

Answer 33

a patch of white thickening of squamous epithelium that may occur in the oral cavity, penis, or vulva and gives rise to squamous carcinoma

Question 34

____ is a lesion related to leukoplakia, but often already carcinoma in situ so it is beyond precursor.

Answer 34

Erythroplakia

Question 35

Patients with immunodeficiency have a higher incidence of malignancies of certain types; what are they? (3)

Answer 35

1. B-cell lymphoma of B cells infected with EBV
2. Kaposi sarcoma, a proliferation of endothelial cells due to HHV8
3. Squamous cell carcinomas of cells infected with oncogenic HPV

Question 36

What is the difference between lymphomas and leukemias?

Answer 36

lymphomas are solid hematologic malignancies and leukemias are liquid hematologic malignancies.

Question 37

NF is an autosomal dominant disorder caused by mutations in the TSG ____, which has what function? What is the cellular phenotype of the NF mutation?

Answer 37

neurofibromin - a negative regulator of Ras; mutation in NF leads to Ras hyperactivity (hence tumor development)

Question 38

Patients with NF1 have what clinical signs/symptoms?

Answer 38

learning disabilities, seizures, skeletal abnormalities, vascular abnormalities, pigmented nodules of the iris (Lisch nodules), and pigmented skin lesions (axillary freckling and café au lait spots) in various degrees.