PAEDIATRIC CANCER Flashcards

1
Q

most common childhood cancers

A
  • leukaemia
  • brain and spinal cord
  • lymphomas
  • soft tissue sarcomas
  • neuroblastoma
  • renal tumours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

leukaemia causes and risk factors

A

radiation
infections
chemical exposure
previous chemotherapy (mother)
genetic conditions
race
maternal smoking

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

hyperdiploid

A

a cell that has too many copies of chromosomes

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

children with hyperdiploid cancer

A
  • generally good prognosis
  • respond very well to chemotherapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

molecular pathology of leukaemia - too many chromosomes

A

about 20% to 25% of children with ALL have more than 50 copies of chromosomes per cell

typically more copies of chromosomes 4, 11 and 17 inside the leukemic cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

hypodiploid

A
  • too few chromosomes
  • less than 44 copies
  • prognosis not as optimistic as hyperdiploid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

molecular pathology of leukaemia - chromosomal translocation

A

inside leukaemic cells, part of a chromosome can separate itself and attach to other unrelated chromosomes, producing new chromosomes that express genes in different ways

when chromosomes spontaneously rearrange themselves this way - translocation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

problems with chromosomal translocation in children with ALL

A

problems arise when the translocation produces a new gene that instructs the cell to do things it normally wouldn’t (like divide uncontrollably)

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

most frequent translocation that occurs inside leukaemic cells in children 2-9 years old

A
  • when parts of chromosome 12 and 21 fuse together
  • this translocation represents about 25% of all childhood ALL cases, there are too many B-cell lymphoblasts in the blood and bone marrow
  • also possible to find cells with chromosome 9 and 22 translocated, also called philadelphia chromosome positive, more common in children over 10
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

long-term morbidities following paediatric ALL treatment

A
  • secondary cancers
  • cardiovascular diseases
  • hepatic dysfunction
  • peripheral neuropathy
  • infertility/hormonal disturbance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

difference between treating adult and children cancers

A

ADME
faster absorption and faster elimination in children
paediatric medication errors - dose and safety

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

why are most drugs for children administered orally

A
  • easier to swallow
  • cheaper to manufacture
  • less painful than injection
  • more convenient to administer
  • less traumatic for carer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

the degree of drug absorption through gut wall depends on many factors which differ between adults and children, this includes:

A
  • pH of environment in stomach or gut
  • volume of acidic gastric fluids
  • rate of stomach emptying and rate of gut motility
  • gut microbiome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

getting the correct dose into the children

A
  • often put in foodstuffs (do the properties of food alter drug characteristics)
  • does the child eat/drink it all
  • taste masking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

potential administration routes in children

A

mucosal
rectal
skin patch
intramuscular

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

mucosal drug administration in children

A

bypasses first-pass metabolism
i.e. midazolam or lolly (fentanyl)
BUT EXPENSIVE

17
Q

rectal drug administration in children

A

rich blood supply near the arteries
absorption by this route in children is variable long lag time to adsorption

BUT UNCOMFORTABLE FOR CHILD AND CARER - TRAUMATIC

18
Q

skin patch drug administration in children

A

fentanyl
care in children as skin thickness and blood flow highly variable

but: drug leaks long time after patch removed

19
Q

intramuscular drug administration in children

A

causes pain
lose trust of child
distressing

very good bioavailability BUT avoided due to pain and trauma - especially if repeat administrations required

20
Q

absorption in children

A
  • gastric pH higher (less acidic)
  • gastric emptying slowed in under 1-year-olds
  • gastric volume is smaller
  • reduced bile acids and bile flow
  • pancreatic enzymes lower
21
Q

drug factors in drug distribution

A

mostly depend on whether drug crosses membranes and similar to absorption (different in children)

22
Q

patient factors in drug distribution

A
  • differences between adults and children in drug distribution because of body composition and protein binding
  • other physiological factors such as neuromuscular junction, muscle and fat content, different proteins etc.
23
Q

metabolism

A
  • metabolism of drugs is dependent on the liver and its blood flow
  • hepatic blood flow reduced in neonates and infants
  • enzyme systems involved in metabolism very different in varying ages
  • renal efficiency in neonates is decreased
24
Q

childhood obesity

A
  • increasing yearly
  • affects protein binding, blood flow rate, increased tissue volume and perfusion
  • traditionally use weight-based dosing - often don’t choose correct body size metric
25
Q

biggest issue in paediatrics

A

FORMULATIONS AND TASTE

26
Q

other issues in managing childhood illness

A
  • access - lack of child-appropriate formulations, excipients not child-friendly, marketed for adults
  • risk to companies - children are still developing, risk of further abnormalities
27
Q

clinical trials for paediatrics

A
  • need to be minimally invasive
  • few blood samples and pooled data
  • non-invasive
  • ethics