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Flashcards in Cytotoxic Therapy Deck (20)
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1
Q

How are cytotoxic drugs classified?

A

As cell cycle specific or non-cell cycle specific

2
Q

What are the general characteristics of cell cycle specific agents?

A

Tumour specific, duration of exposure more important than dose

3
Q

What are the two main types of cell cycle specific agents?

A

Anti-metabolites = impair nucleotide synthesis or incorporation
Mitotic spindle inhibitors

4
Q

What are some examples of anti-metabolites?

A

Methotrexate = inhibit dihydrofolate reductase
6-mercaptopurine/fludarabine = incorporated into DNA
Hydroxyurea =impairs deoxynucleotide synthesis

5
Q

What are some examples of mitotic spindle inhibitors?

A

Vinca alkaloids = vincrisitne

Taxotere

6
Q

What are the general characteristics of non-cell cycle specific agents?

A

Non-tumour specific = damage normal stem cells

Cumulative dose more important than duration

7
Q

What are some examples of non-cell cycle specific agents?

A

Alkylating agents, platinum derivatives, cytotoxic antibiotics

8
Q

What is the action of alkylating agents?

A

Bind covalently to DNA bases = produce DNA strand breaks by free radical production (e.g chlorambucil)

9
Q

What are some examples of platinum derivatives?

A

Cis-platinum and carboplatin

10
Q

What is the action of cytotoxic antibiotics?

A

Reversible DNA intercalation = impairs RNA synthesis, breaks DNA strands by free radical production (e.g anthracycline)

11
Q

What are the immediate side effects of cytotoxic drugs?

A

Affects rapidly dividing organs = bone marrow suppression, gut mucosal damage, hair loss (alopecia)

12
Q

What are some examples of side effects associated with specific cytotoxic drugs?

A

Neuropathy with vinca alkaloids
Cardiotoxicity with anthracycline
Nephrotoxicity with cis-platinum

13
Q

What are some long term side effects associated with cytotoxic drugs?

A

Infertility and secondary amenorrhoea with alkylating agents

Cardiomyopathy with anthracyclines

14
Q

What is the purpose of chemotherapy?

A

Slows tumour doubling time

15
Q

What are some different mechanisms of chemotherapy drug resistance?

A

Decreased drug accumulation = MDR-1/PGP
Altered drug metabolism = cyclophosphamide
Increased DNA repair = cis-platinum
Altered gene expression = reduced topoisomerase II

16
Q

What limits chemotherapy effectiveness?

A

Myelosuppression

17
Q

How can myelosuppression during chemotherapy be prevented?

A

Use of haemopoietic growth factors
Combine myelosuppressive and non-myelosuppressive agents
Intensify dose of active drugs and stem cell rescue

18
Q

What are the sources of stem cells for transplant?

A

Blood or bone marrow

Autologous or allogenic (sibling/unrelated)

19
Q

What are the steps in progenitor cell transplantation?

A

Cell collection - myeloblative therapy - progenitor cell reinfusion - bone marrow regeneration

20
Q

How is chronic myeloid leukaemia treated?

A

Targeted tyrosine kinase therapy