Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HD > Cancer in children > Flashcards

Cancer in children Flashcards

1
Q

How many children <15 are affected by cancer in the UK?

A

1 in 500

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 3 most common types of cancer in 0-14 year olds?

A
  1. leukaemia
  2. CNS
  3. lymphoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 3 most common types of cancer in 15-19 year olds?

A
  1. lymphoma
  2. carcinomas + melanomas
  3. CNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What kind of health and quality of life issues are faced by cancer survivors in terms of:

a. growth + development
b. psychosocial
c. organ function
d. fertility + reproduction
e. cancer

A

Growth + development:

  • sexual development
  • intellectual function
  • emotional + social maturation
  • skeletal maturation
  • linear growth

Psychosocial:

  • employment
  • education
  • health insurance
  • chronic symptoms
  • physical /body images
  • mental health

Organ function:

  • cardiac
  • endocrine
  • GI + hepatic
  • genitourinary
  • musculoskeletal
  • neurological
  • pulmonary

Fertility + reproduction:

  • fertility
  • health of offspring
  • sexual functioning

Cancer:

  • subsequent neoplasms
  • recurrent primary cancer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe how oncogenes work, how they are activated, and give examples.

A 
Oncogenes act by a gain of function 
They are dominant, therefore activation of one allele is sufficient to cause cancer 
Activated by:
- mutation
- chromosome translocation 
- gene amplification 
- retroviral insertion 
examples: CTNNB1, MYCN, MDM2, ALK etc etc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe how tumour suppressor genes work, how they are inactivated, and give examples.

A 
Act by loss of function
they are recessive (inactivation of both alleles is necessary)
inactivated by:
- mutations
- deletions
- DNA methylation (epigenetics)

Cause a predisposition to cancer
examples: RB, WT1, TP53 PTCH1, BRCA1/2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe Knudson’s two-hit model.

A 
deletion or inactivation of both copies of a gene = tumorigenesis 
first allele is either deleted/mutated = inherited or somatic 
loss of function of 2nd allele via:
- loss of allele
- loss + duplication 
- chromosome deletion 
- mutation 
- recombination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a Wilm’s tumour? How many children does it affect? What is its usual presentation + mode of spread?

A

It is a tumour of the kidney (nephroblastoma)
Affects 1/10,000 children (usually under 5)
Usually presents as asymptomatic abdominal mass
Spread via lymphatics/bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What somatic genetic alterations are involved in the molecular pathology of Wilm’s tumour?

A
  • inactivated WT1, wTX, TP53 genes
  • activated CTNNB1 (beta-catenin gene)
  • epigenetic alterations at IGF2/H19 locus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What germline genetic alterations are involved in the molecular pathology of Wilm’s tumour?

A 
WT1 gene (WAGR = Wilm’s tumour, Aniridia, Genito-urinary abnormalities, mental Retardation)
IGF2/H19 locus (BWS = Beckwith-Wiedeman Syndrome)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the cellular origins of Wilm’s tumour?

A

Arises from pluripotent embryonic renal precursors

Usually contains 3 cell types: blastema, epithelia, stroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does a bilateral Wilm’s tumour indicate?

A

hereditary predisposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why can absence of WT1 result in a Wilm’s tumour?

A

Prevents differentiation and maintains cells in an immature state - can lead to tumour formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a retinoblastoma? What % of cases are heritable? What are the symptoms?

A

Tumour of the retina
Heritable in ~30% of cases (+ve family history; bilateral or multifocal; germline mutation of RB1 gene)
Symptoms = leukocoria (white pupil), eye pain, redness, vision problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the cellular origins of retinoblastoma?

A

cone precursor cells

signalling pathways promote cell survival after loss of RB1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does a loss of RB1 affect a cell’s cycle?

A

Normal cells: Phosphorylation of RB1 will release E2F which will induce G1-S transition, allowing cells to move through the cell cycle

Cancer cells without RB1: e2F will be free to induce G1-S transition

17
Q

What role do MYCN and MDM2 play in the development pot retinoblastoma?

A

MYCN - when activated allows abnormal proliferation of cone precursors

MDM2 - when over expressed/amplified will suppress p53 = cell precursors are unable to become apoptotic

18
Q

What is a neuroblastoma? What % of cases have metastasised by the time of diagnosis?

A

Tumour of the sympathetic nervous system - usually arising in the adrenal gland or sympathetic ganglia

> 50% of cases have metastasised at the time of diagnosis

19
Q

What is significant about neuroblastoma 4S?

A

Metastatic disease to the liver and skin

Often shows spontaneous maturation and regression

20
Q

What is the cellular origin of neuroblastoma?

A

Sympathy-adrenal lineage of the neural crest cells during development

21
Q

What are the key genes involved int he development of a neuroblastoma?

A

MYCN (high risk)
ALK (high risk + hereditary)
PHOX28

Medium/intermediate risk = numerical chromosome gains

22
Q

What targeted therapy is there for neuroblastoma?

A

Crizotinib = for ALK mutations

23
Q

What is the usual clinical presentation of Acute Lymphoblastic Leukaemia (ALL)?

A
  • Most common malignancy in children
  • Most frequent cause of death from cancer <20 yr age group

Symptoms:

  • bruising/bleeding
  • pallor or fatigue due to anaemia
  • infection due to neutropenia
  • due to clonal expansion of immature lymphocytes (lymphoblast/blast cells)
24
Q

What is the cellular origin of ALL?

A

Can be traced back to haematopoiesis

Pro-B: CD19+ on the cell surface
- this is ALL with a MLL translocation (most common)
Pre-B: CD19+ and CD10+
- this is ALL with high hyperploidy or TEL-AML1 translocation

25
Q

What are some high risk groups for developing cancer in children?

A
  • genetic predisposition = will likely develop tumour in the perinatal period
  • congenital malformations = will result in a bilateral or multifocal tumour formation
  • cancer is close relatives
  • same rare tumour in >1 family member (e.g. familial retinoblastoma)
  • different types of tumours occurring in family members (e.g. Li-Fraumeni syndrome)

HD (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions