Cytotoxic & Methotrexate

Question 1

Cytotoxic drugs

Answer 1

Table in phone of many different cytotoxic drugs - EXAM Q could ask which 1 is which.

Vinca alkaloids common Q - how to administer

These cytotoxic drugs have both anticancer activity and can damage normal tissue.
- Given to prolong life and cure/Palliate symptoms.
- Cause many AEs so balance benefit vs risk
- AEs occur over days/weeks after giving drugs
- Most cytotoxic drugs are teratogenic and AVOID in pregnancy esp. 1st trimester.
- Exclude pregnancy b4 treatment

Neoadjuvant (given b4 surgery to help)
(Chemo + radio) OR (chemo + surgery) OR chemo + surgery + radio)
- Initial chemo is aimed at shrinking primary tumour which makes local therapy less destructive/more effective.

Adjuvant
Same routines as neoadjuvant
- Prevent cancer after neoadjuvant

Question 2

Guidelines to handle cytotoxic

Answer 2

Trained personnel must be trained to reconstitute cytotoxics

Wear protective clothing (gloves, mask etc)
- Protect eyes and should know 1st aid

Pregnant staff need to avoid cytotoxic exposure

Use local proecedures to deal with spillages and safe disposal.

Monitor staff exposure to cytotoxics

Safe systems for cytotoxics
MDT needed to give cytotoxic for treatment
Should have written protocol/Treatment plan for cytotoxic drugs.
Injectable only dispensed if already prepared for PT

Oral cytotoxics need to be given with clear instructions on use

Question 3

Safety info of cytotoxics

Answer 3

Risk of wrong dosing. should have written protocol/Treatment plan. Pt should have info on details of drug, treatment plan, arrangements for monitoring.

• Pregnancy & Reproductive function -
• Most are teratogenic. AVOID ESP. in 1st Exclude preg b4 treatment with cytotoxics,
• Give contraceptive advice B4 treatment.

Question 4

AEs of Cytotoxics (EXAM Q)

Answer 4

• Reversible Alopecia
• NV - Prophylaxis for NV is given (next card). NV can be either acute (within 24 hrs), delayed (happens 24 hrs after treatment) or anticipatory (happen by thinking it will happen). Last 2 harder to control. Some pts more sus to NV (women, <50s, anxious pts, Pt exp. motion sickness, repeated exposure to drug).
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• Extravasation (accidental leakage from vein/tube in to surrounding areas - damages normal cells) Reduce risk via trained staff.
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• Oral mucositis - sore mouth (happens with Fl.A.Me [Fluorouracil, anthracyclines, Methotrexate]) - Prevent with good oral hygiene, use saline/mouthwash. Fl- sucking ice chip can help.
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• Tumour lysis syndrome - Rapid destructions of cancer cells can lead to other bad wastes leaking to other healthy cells. *Symptoms: hyperkalaemia, hyperuricaemia, hypocalcaemia, hyperphosphotnaemia, renal damage, arrhythmias.
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• Hyperuricaemia - present in leukaemia, high grade lymphoma. can lead to gout as high uric acid. or can cause acute renal failure =AKI. Treat with allopurinol 24 hrs b4 treating tumour. ALT febuxostat

*Bone marrow suppression (myelosupression):
- ALL cytotoxics except vincristine & bleomycin (EXAM Q)
- FBC b4 treatment, Treat any infection b4 starting, Treat fever with antibiotics.
- PT need to see DR ASAP if having infection signs.
- Blood transfusion for anaemia.

Question 5

emetogenic level of cytotoxics

Answer 5

Table in phone (more drugs)

Mild - methotrexate, vinca alkaloids
Moderate - High dose methotrexate
Highly - cisplatin

• Q will only comes as EMQ

Prevention
ACUTE symptoms:
Low risk - dexamethasone, lorazepam

DELAYED Symptoms:
Moderate - dexamethasone + 5HT3 antagonist (setrons)
High - dexamethasone + aperepitant, metoclopramide, rolapitant

ANTICAPATORY - Lorazepam

Question 6

Anthracyclines AEs/Other info

Answer 6

*Anthracycline induced cardiotoxicity

• Extravasation
• Mucositis and myelosuppression
• Folinic acid used to reverse methotrexate affects/Overdose
• Urothelial toxicity - Haemorrhagic cystitis.- Treat with MESNA

OTHER
Many cytotoxics act as radiomimetic - AVOID simultaneous radiotherapy

EXAMPLES -
Doxorubicin, danurubicin, epirubicin, idarubicin
IMPORTANT AES: ALL red urine, Cardiotoxicity

Doxorubicin can cause ;iposomal formulations which may reduce cardiotoxicity & local necrosis BUT can lead to hand-foot syndrome (painful reddening, skin eruptions) - TREAT VIA Cooling hands and feet, AVOID clothing over them

Question 7

Alkylating drugs

Answer 7

Most widely used

Act by damaging DNA so stop cell replication

EXAMPLES: Cyclophosphamide, ifosfamide, melphalan

Question 8

Methotrexate (EXAM Q)

Answer 8

T100 notes

Know AEs, Monitoring, Interactions. MOA

Interactions (EXAM Q)
NSAIDs/Aspirin/Penicillins - Increase toxicity risk

PPIs - Decrease clearance of methotrexate.

Statins/Most antibiotics - Increase hepatotoxicity risk

Trimethoprim - Increase risk of AEs with methotrexate