Topics 1-2 Etiology and Epidemiology

Question 1

Topic 1. Etiology:

• About what % of these etiological factors is important in carcinogenesis?*
• -Environmental (chemical, physical)*
• -Infections (viruses, bacteria, worms)*
• -Hereditary/genetic*

Answer 1

• Environmental: 80-90%
• Infections: 5-10%
• Genetic: 5%

Question 2

Topic 1. Etiology:

About what percentage of tumors are acquired/sporadic, meaning they’re caused by mutations resulting from the accumulation of environmental damages in somatic cells?

Answer 2

Over 95%

Question 3

Topic 1. Etiology:

• What does IARC stand for?*
• What is it?*

Answer 3

International Agency for Research on Cancer

A division of the WHO that classifies carcinogens based on scientific evidence (Category 1, 2/A, 2/B, 3, 4)

Question 4

Topic 1. Etiology:

• What is category 1 of the IARC?*
• What are some examples?*

Answer 4

Proven carcinogens:

tobacco smoke, asbestos,
alcohol, UV, ionising radiation, air
pollution, contraceptives, processed
meat products

Question 5

Topic 1. Etiology:

• What is category 2/A of the IARC?*
• What are some examples?*

Answer 5

probable carcinogens
bitumen (tar), DDT, anabolic steroids, red meat

Question 6

Topic 1. Etiology:

• What is category 2/B of the IARC?*
• What are some examples?*

Answer 6

possible carcinogens:
phenobarbital, chloroform, fiberglass, gasoline, diesel oil, carbon black, lead, chrome, nickel

Question 7

Topic 1. Etiology:

• What is category 3 of the IARC?*
• What are some examples?*

Answer 7

not classifiable as to carcinogenicity

caffeine, tea, PVC, printing inks, magnetic and electric fields, paracetamol, diazepam)

Question 8

Topic 1. Etiology:

• What is category 4 of the IARC?*
• What are some examples?*

Answer 8

probably not carcinogenic

caprolactam (prob not important to know, something used in fibers/plastics)

Question 9

Topic 1. Etiology:

What is the increased risk of cancer in organ transplant recipients?

Answer 9

Double the risk, due to immunosuppression

HIV/AIDS patients have increased risk for the same reason

Question 10

Topic 1. Etiology:

How does familial inheritance of a tumor work?

Answer 10

Mutations occur in the gametes of a parent that predispose their offspring to a cancer after further mutations are acquired. Every cell of the offspring is affected.

The combination of the acquired mutation + new somatic mutation makes it likely to develop a tumor at a young age.

Question 11

Topic 1. Etiology:

• What types of tumors are typically caused by HPV?*
• (5 listed)*

Answer 11

Cervical, penile, anal, bladder, head/neck

Question 12

Topic 1. Etiology:

What types of HPV typically cause cancer?

[I’m focusing on maximum 7 of them, but a lot are listed]

Answer 12

About 70% of cervical cancers are from HPV 16 and 18

6, 11: important in laryngeal cancer

31, 33, 45 also important for genital cancers

The e-book also includes: 35, 39, 45, 51, 52, 56, 58, 59, 68, 73, 82… but I don’t think anyone expects you to remember all that

Question 13

Topic 1. Etiology:

• What types of neoplasia are associated with hepatitis C?*
• Which neoplasia is hepatitis B associated with?*

Answer 13

Lymphoma

Aplastic anemia

Hepatocellular carcinoma (also for hepatitis B)

Question 14

Topic 1. Etiology:

What type of neoplasia is human polyomavirus associated with?

Answer 14

Childhood neuroblastoma

Related to BK and JC virus

[Just gonna put a note in here to remember that HTLV-1 virus causes T cell leukemia/lymphoma, but that’s in the name of the virus so it shouldn’t require its own card]

Question 15

Topic 1. Etiology:

Which herpes viruses can cause neoplasia?

Answer 15

EBV

CMV

HHV-8 (aka Kaposi-sarcoma associated virus)

Question 16

Topic 1. Etiology:

What 3 main types of neoplasia are associated with Epstein-Barr Virus / EBV?

Answer 16

Burkitt lymphoma

Hodgkin lymphoma

Nasopharyngeal carcinoma

(+ some others not mentioned in e-book.. primary CNS lymphomas, some stomach cancers..)

Question 17

Topic 1. Etiology:

What type of neoplasias can occur from Helicobacter pylori infection?

Answer 17

Stomach cancer:

gastric adenocarcinoma + MALT lymphoma

Question 18

Topic 1. Etiology:

What type of neoplasias can result from either Schistosoma haematobium or S. japonicum infection?

Answer 18

Squamous cell bladder carcinoma, colorectal carcinoma, stomach carcinoma

Liver carcinoma

Question 19

Topic 1. Etiology:

• Which genes are involved in hereditary breast and ovarian cancer syndromes?*
• Which other tumors can occur as a result?*

Answer 19

BRCA1, BRCA2

Besides breast and ovarian cancers, prostate, and pancreatic tumors

Question 20

Topic 1. Etiology:

• What gene is responsible for hereditary retinoblastoma?*
• What other tumor often arises in people with the mutation?*

Answer 20

RB1

Osteosarcoma

Question 21

Topic 1. Etiology:

What gene is responsible for Wilms tumor (nephroblastoma)?

Answer 21

WT-1

(transcription factor that regulates urogenital development)

Question 22

Topic 1. Etiology:

• What gene is mutated in familial adenomatous polyposis (FAP)?*
• What tumors can arise as a result of this mutation?*

Answer 22

APC

Gastrointestinal (especially colorectal),

e-book says also brain, thyroid, retina

Question 23

Topic 1. Etiology:

What types of tumors often arise in Lynch syndrome?

Answer 23

Colorectal cancer (Lynch syndrome is also known as hereditary non-polyposis colorectal cancer)

Risk of endometrial, ovarian, stomach and several others

Question 24

Topic 1. Etiology:

What types of cancers are more likely in Peutz-Jegher syndrome?

Answer 24

PJS is associated with hamartomatous polyps throughout the GI, but these only a small risk of malignant transformation

PJS has an increased risk of cancer all over the body (GI, breast, ovary, uterus, testicles, pancreas)

Question 25

Topic 1. Etiology: ## Footnote *What types of cancers are more likely in **Ataxia telangiectasia**?*

Answer 25

lymphoma, leukaemia, breast, adrenal gland ATM mutation -\> inability to fix double stranded breaks. Neurodegeneration occurs (hence ataxia) + dilated vessels (telangiectasia)

Question 26

Topic 1. Etiology: * Which gene is mutated with **Li-Fraumeni** syndrome**?* * What cancers are likely to occur?*

Answer 26

**TP53** Many cancers can occur as p53 is often the last mutation to make a cell neoplastic. E-book says sarcomas, breast, brain, leukemia

Question 27

Topic 1. Etiology: ## Footnote *What types of cancers are likely to occur with **Multiple Endocrine Neoplasia / MEN1** mutation?*

Answer 27

**Insulinoma** **Gastrinoma** **Hypophyseal tumors** **Parathyroid tumors** (3 Ps: **p**ituitary adenoma, primary hyper**p**arathyroidism, and **p**ancreatic endocrine tumors)

Question 28

Topic 1. Etiology: ## Footnote *What types of cancers are likely to occur with **Xeroderma pigmentosum**?*

Answer 28

**Basal cell carcinoma** **Melanoma** (XPA mutation \> *nucleotide excision repair* is faulty as a result, and UV light becomes much more dangerous)

Question 29

Topic 1. Etiology: ## Footnote *What type of cancers are more likely to occur in **Von Hippel-Lindau Syndrome / VHL** **mutation**?*

Answer 29

**Clear cell renal carcinoma** (most important) + Pheochromocytoma, Retinal angioma

Question 30

Topic 2. Epidemiology: * For the most common causes of mortality, **where does cancer rank** in developed or medium-devloped countries?* * In Hungary, how often is cancer typically a cause of death? How does it compare to the rest of Europe?*

Answer 30

Ranks **2nd** as a cause of mortality (1st is cardiovascular disease) As of 2014, about **1 in 4** (technically 28.7%) of people in Hungary die from cancer. Hungary has the **highest standardized death rate** **in Europe**, and Eastern Europe in general has higher rates than the rest of Europe

Question 31

Topic 2. Epidemiology: * By **incidence**, what are the **top 3 types of cancer** in Hungary in general?* * (not including non-melanoma skin cancers)* * How is cancer incidence different for just men or just women?*

Answer 31

General: **1. Lung 2. Colorectal 3. Breast/prostate** (These three make up approx 40% of new cancer cases) **Men**: 1. lung, 2. colorectal, 3. prostate (the same) **Women**: 1. breast, 2. lung, 3. colorectal (women are less likely to smoke and more likely to have breast cancer than men are to have prostate cancer; E-book text says breast \> lung \> colorectal, but the graph they used said B \> C \> L)

Question 32

Topic 2. Epidemiology: ## Footnote *By **mortality,** what are the **top 3 types of cancer** in Hungary for men vs women?*

Answer 32

Men: **lung, colorectal, prostate** ## Footnote (the same as incidence.. male lung cancer is almost always deadly) Women: **lung, breast, colorectal** (different than incidence, which is breast, colorectal, lung.. lung cancer is more deadly than breast cancer, which has been improving in mortality rates)

Question 33

Topic 2. Epidemiology: ## Footnote * What are some of the general principles of the **European Code against Cancer**?* * [this is mostly standard stuff to avoid cancer so just be familiar rather than memorize the whole thing]*

Answer 33

- Don't smoke, don't use tobacco products - Be a healthy body weight, physically active, eat healthy - Eat vegetables/fruits, high fiber, low calorie - Avoid processed meat, limit red meat and salt - Limit alcohol intake - Avoid too much sun, use sunscreen - Avoid work-related exposures, follow safety protocols - Reduce potential radon exposure in homes - Breastfeeding reduces breast cancer risk for mother, so breastfeed if possible - Get hepatitis B and HPV vaccines - Undergo standard screening procedures (e.g. colonoscopies, breast exams, cervical exams)