2. Principles of chemotherapy Flashcards
What is chemotherapy?
Cytotoxic drugs that kill cancerous cells (cells that uncontrollably divide and are abnormal) to stop it from spreading
Cytotoxic drug classes
- ANTHRACYCLINES:
- VINCA ALKALOIDS:
- ANTIMETABOLITES:
- ALKYLATING DRUG:
- PLATINUM/DNA CROSS LINKERS
- TAXANES
- OTHER ANTIBIOTICS
Anthracycline cytotoxics
ANTHRACYCLINES:
* Doxorubicin
* Daunorubicin
Vinca alkaloids cytotoxics
VINCA ALKALOIDS:
* Vinblastine
* Vincristine
[Vin-] (more)
Antimetabolite cytotoxics
ANTIMETABOLITES:
* Mercaptopurine
* Methotrexate
* Fluorouracil
* Gemcitabine (more)
Alkylating cytotoxics
ALKYLATING DRUG:
* Cyclophosphamide
* Melphalan
* Chlorambucil (more)
Platinum cytotoxics
PLATINUM/DNA CROSS LINKERS
* Cisplatin
* Carboplatin
Taxane cytotoxics
TAXANES
* Docetaxel
* Paclitaxel
Cytotoxic drug classes (broken down)
ANTHRACYCLINES:
* Doxorubicin
* Daunorubicin
VINCA ALKALOIDS:
* Vinblastine
* Vincristine
[Vin-]
ANTIMETABOLITES:
* Mercaptopurine
* Methotrexate
* Fluorouracil
* Gemcitabine (more_
ALKYLATING DRUG:
* Cyclophosphamide
* Melphalan
* Chlorambucil (more)
PLATINUM/DNA CROSS LINKERS
* Cisplatin
* Carboplatin
TAXANES
* Docetaxel
* Paclitaxel
OTHER ANTIBIOTICS
* Bleomycin
* Mitomycin
Types of cytotoxic drugs
Neo-adjuvant - initial chemotherapy to shrink primary tumour before radiotherapy/surgery
Adjuvant - used with radiotherapy/surgery
How should chemotherapy be handled?
- Only trained staff in a designated area
- Must wear protective gear
- Must have spills and waste disposal procedures
- Must monitor staff exposure
PREGNANT STAFF MUST AVOID
Ways to reduce risk of incorrect dosing of oral cytotoxic drugs
Non-specialists who prescribe or administer chemotherapy MUST have access to written protocols or treatment plan
During dispensing,
* confirm dose
* Patient must have written information
Cytotoxic drug side effects (#10)
- Alopecia
- Extravasation
- Oral mucositis
- Pregnancy and fertility
- Venous thromboembolism
- Urothelial toxicity
- Hyperuricaemia
- Bone marrow suppression
- Nausea and vomiting
- Tumour lysis syndrome
As cytotoxic drugs inadvertently target healthy cells, this results in many side effects
Pregnancy and cytotoxic drugs
what it is, how it should be managed and common causative drugs
Most cytotoxic drugs are teratogenic. Patients that are pregnant are seen by specialists.
Pregnancy must be excluded before treatment and effective contraception must be used during and sometime after treatment.
Cytotoxic drugs and fertility
what it is, how it should be managed and common causative drugs
Cytotoxic drugs inadvertently target healthy cells such as sex cells (sperm and eggs). This causes infertility.
Alkylating drugs and procarbazine can cause permanent male infertility. Patient should be counselled on storing their sperm.
Can cause early menopause in women
Bone marrow suppression and cytotoxic drugs
what it is, how it should be managed and common causative drugs
All cytotoxic drugs cause bone marrow suppression EXCEPT vincristine and bleomycin
Patients must report signs of infection or bleeding disorder (sore throat, mouth ulcers, bruising, bleeding).
Patients on cytotoxics must AVOID live vaccines - CONTRAINDICATED
Treatment of fever in neutropenic patients
Broad spectrum-antibiotic or filgrastim
Treatment of iron-deficiency anaemia
Red blood cells transfusion or erythropoietin to stimulate red blood cell production (warning: can cause tumour progression and death)
Cytotoxic drugs and oral mucositis
what it is, how it should be managed and common causative drugs
Cytotoxic drugs Inadvertently target healthy mucosal cells that line the gastrointestinal tract.
Oral mucositis is a sore and inflammed mouth.
Patients must be advised on good oral hygience: rinse mouth regularly, use saline mouthwash, use soft toothbrush 2-3x daily and suck on ice cubes
Anthracyclines and antimetabolites commonly cause this
Treatment for methotrexate-induced oral mucositis and bone marrow suppression
Folinic acid
Drugs with high emetogenic potential
- Cisplatin
- Dacarbazine
- High-dose cyclophosphamide
CDHC
Drugs with moderate emetogenic potential
- High-dose methotrexate
- Taxanaes (paclitaxel)
- Doxorubicin
- Cyclophosphamide
- Mitoxantrone
hMMCDT
Drugs with mild emetogenic potential
MEFV
- Methotrexate
- Vinca alkaloids
- Fluorouracil
- Etoposide
Types of nausea and vomiting associated with cytotoxic drugs
- Anticipatory, occurs before treatment:
- Acute <24 hours of chemotherapy administration
- Delayed >24 hours of chemotherapy administration:
Treating nausea and vomiting associated with cytotoxic drugs
Anticipatory: Lorazepam (amnesia, sedative, anxiolytic effects)
Acute ** <24hrs of chemotherapy administration:**
* LOW RISK: Dexamethasone or Lorazepam
* HIGH RISK: 5-HT3 antagonist + aprepitant + dexamethasone
Delayed >24 hours of chemotherapy administration:
* MODERATE EMETOGENIC: Dexamethasone + 5-HT3 antagonist
* HIGH EMETOGENIC: Dexamethasone + aprepitant OR rolapitant + metoclopramide
Cytotoxic drugs and venous thromboembolism
Tamoxifen and thalidomide increase the likelihood of venous thromboembolism
Patients must report signs of: breathlessness, chest pain, swelling in the calf of one leg
Cytotoxic drugs and urothelial toxicity
symptoms, cause and treatment
Where the urothelial cells that line the urinary tract become inflammed which can lead to haemorrhagic cystitis (when the bladder becomes inflammed and causes urinary symptoms) and blood in urine.
More common with acrylating drugs: cyclophosphamide and ifosfamide.When the drugs are metabolised acroline is produced and is responsible for urothelial toxicity
Treated with MESNA which reacts with the acroline metabolites
Cytotoxic drugs and tumour lysis syndrome
This is the rapid destruction of cancer cells. More likely to happen in patients with lymphomas and leukemias.
Clinical features:
* High potassium = can cause arrthymias
* High calcium
* High urea = can cause crystals which can enter kidneys and cause damage -> renal failure
Patients at increased risk are patients with existing kidney impairement, dehydration
Cytotoxic drugs and hyperuricaemia
High-grade lymphomas and leukaemia may contain high calcium. Made worse by chemotherapy and leads to gout
Allopurinol is used to treat hyperuricaemia and must be started 24 hours before chemotherapy
Febuxostat is used to treat hyperuricaemia and must be started 2 days before chemotherapy
Rasburicase is used to treat haemotological cancer
Extravasation and cytotoxic drugs
When intravenous cytotoxic drugs leak from the veins into surrounding tissue. Musy be quickly dealt with to prevent damage to local tissue. COMPLICATIONS = amputation
Can happen with any drug administered intravenously
Can be particularly irritable with vinca alkaloids and anthracyclines
Make sure to stop the infusion, and do not remove the line. Disconnect the IV tube from the cannula, aspirate any remaining drug from the cannula
Vinca alkaloids mechanism of action
Bind to tubulin threads to arrest dividing cells in metaphase
Vinca alkaloids
route of administration, side effects
Route of administration:
- NEVER INTRATHECALLY = FATAL
* - adult/adolescents: doses in 50ml mini infusion bag
* Children: doses by syringe
Side effects:
* neurotoxicity
* Severe bronchospasm
Anthracycline Cytotoxic antibiotics
Are radiomimetics, so must be avoided with radiotherapy
Anthracycline antibiotics typially end in “-rubicin”, e.g doxorubicin
Anthracycline cytotoxic antibiotics
properties and side effects
- Cardiotoxicity
- Extravasaion injury
- Colours urine red
Liposomal Dexrazoxane is used to reduce cardiotoxicity and extravasation injury.
Liposomal formulations can cause hand and foot syndrome. Can be prevented by cooling hands and feet, avoiding socks and gloves for 4-7 days after treatment
Cytotoxic drug side effects
list them
- Extravasation
- Hair loss
- Venous thromboemolism
- Immunosuppression (bone marrow suppression, neutropenia)
- Oral mucositis
- Nausea and vomiting
- Iron deficiency
