Chemotherapy

Question 1

How does tumour size affect the growth fraction?

How does growth fraction affect sensitivity to chemotherapeutic agents?

Answer 1

• Larger tumour size= Lower growth fraction

- Lower growth fraction= less sensitive to chemotherapeutic agents

Question 2

List the 4 main groups of Cytotoxic Chemotherapeutic agents and their target

Answer 2

1. Antimetabolites: Interfere with DNA synthesis
2. Alkylating agents: Interfere with DNA Transcription and Replication (Cisplatin, Oxaliplatin, Carmustine)
3. Intercalating agents: Interfere with DNA Transcription and Replication
4. Spindle poisons: Interfere with mitosis

Question 3

List 2 Antimetabolite drugs

Answer 3

• Methotrexate (Inhibits Dihydrofolate Reductase)

- 5-Fluorouracil (Inhibits Thymidylate Synthase)

Question 4

List 2 types of Spindle Poisons

How do they work?

Answer 4

• Vinca Alkaloids
• Taxanes

Cause polymerisation of Microtubules;

• Taxanes: Promote assembly and Prevent disassembly
• VAs: Prevent spindle formation

Question 5

List 7 key side effects of Chemo

Can cause Neutropenia-> Infection/ Sepsis

Answer 5

• Vomiting
• Alopecia
• Skin toxicity
• Mucositis (Sore mouth/ throat, Diarrhoea, GI Bleed)
• Cardio-toxicity (Cardio-myopathy, Arrhythmias)
• Lung toxicity (Pulmonary fibrosis, O2 therapy can make worse)
• Haematological toxicity

Question 7

Describe the side effect of Alopecia due to Chemo

With what drugs are Alopecia Marked and Minimal?

(Scalp cooling can help)

Answer 7

• Hair thinks at 2-3 weeks
• May be total, may re-grow during therapy
• Marked with Doxorubicin, Vinca Alkaloids, Cyclophosphamide
• Minimal with Platinum compounds

Question 8

Describe Skin Toxicity due to Chemo

Answer 8

Local: Irritation + Thrombophlebitis of veins, Extravasation (vein bursts and agent enters tissue)

General;
- Hyperkeratosis, Hyperpigmentation, Ulcerated pressure sores

Question 9

Using the ‘Chemo Man’, list side effects of Cisplatin and Carboplatin

Answer 9

• Ototoxicity

- Nephrotoxicity

Question 10

Using the ‘Chemo Man’, list side effects of Vincristine and Cyclophosphamide

Answer 10

Vincristine: Peripheral neuropathy

Cyclophosphamide: Haemorhhagic Cystitis

Question 11

Using the ‘Chemo Man’, list a side effect of Blemocyin and Busulfan

Answer 11

Pulmonary fibrosis

Question 12

Using the ‘Chemo Man’, list a side effect of Trastuzumab and Doxorubicin

Answer 12

Cardiotoxicity

Question 13

Using the ‘Chemo Man’, list a side effect of Methotrexate, 5-FU and 6-MP

Answer 13

Myelosuppression

Question 14

List 8 routes of administration of a chemotherapeutic agent

Answer 14

• IV (most common)
• Oral
• SC
• Into a body cavity (Bladder, pleural effusion)
• Intralesional (Directly into a cancerous area)
• Intrathecal (Into CSF, consider LP)
• Topical
• IM (Rarely)

Question 15

List 4 DDIs of Chemo

Answer 15

• Vincristine + Itraconazole-> More neuropathy
• Methotrexate; caution with Penicillins + NSAIDs

Capecitabine and;

• St Johns Wort (inducer)
• Grapefruit juice (inhibitor)

Question 16

List 3 things that need to be monitored during chemo

Answer 16

• Response of the cancer (Imaging, Markers, Marrow)
• Drug levels
• Organ damage (Cr clearance, ECG)

Question 17

Vomiting is a common side effect of Chemo.

Describe the 3 patterns of Emesis due to Chemo

Answer 17

Acute phase: 4-12 hrs

Delayed onset: 2-5 days later

Chronic phase: Can persist up-to 14 days