5.4 chemo

Question 1

What is the major impediment to successful chemotherapy?

Answer 1

Toxicity of drugs to normal tissue

Toxicity to normal cells is the principal barrier and is dose-limiting.

Question 2

Define neoplastic cells.

Answer 2

Cells characterized by persistent proliferation, invasive growth, formation of metastases, and immortality

Neoplastic cells continue to grow until they cause death.

Question 3

Chemotherapy drugs are more toxic to tissues with high growth fraction. Name some of these tissues.

Answer 3

• Bone marrow
• Skin
• Hair follicles
• Sperm
• Gastrointestinal tract

Solid tumors have low growth fraction, while disseminated cancers have high growth fraction.

Question 4

What is the goal of intermittent chemotherapy?

Answer 4

100% kill of neoplastic cells with limited injury to normal tissue

Normal cells have time to repopulate between treatments.

Question 5

List the major toxicities of cancer chemotherapy.

Answer 5

• Bone marrow suppression (Myelosuppression)
• Neutropenia
• Thrombocytopenia
• Anemia
• Digestive tract injury
• Alopecia
• Hyperuricemia
• Extravasation of the skin
• Reproductive toxicity
• Carcinogenesis

Each toxicity has specific implications for patient care and management.

Question 6

What is neutropenia and why is it significant?

Answer 6

Loss of neutrophils leading to increased risk of infection

It is the most serious complication of chemotherapy.

Question 7

True or false: Cytotoxic drugs have selective toxicity.

Answer 7

FALSE

Cancer cells are too similar to normal cells, making selective toxicity difficult.

Question 8

What are the routes of administration for Methotrexate?

Answer 8

• PO
• IM
• IV

Methotrexate is an antimetabolite used in various cancers and rheumatoid arthritis.

Question 9

What is the mechanism of action (MOA) of Vincristine?

Answer 9

Prevents cell division during M phase of the cell cycle

It is a mitotic inhibitor and is ideal for combination chemotherapy due to its bone marrow sparing properties.

Question 10

What is the nadir in the context of chemotherapy?

Answer 10

The lowest neutrophil count occurring between days 10-14

Normal neutrophil count ranges from 2500-7000, with critical levels being <500.

Question 11

Fill in the blank: The mechanism of action of Methotrexate is to disrupt _______.

Answer 11

metabolic processes of cell replication

It is effective only against cells in the active cell cycle.

Question 12

What are the guidelines for drug selection in combination chemotherapy?

Answer 12

• Each drug should be effective by itself
• Different mechanism of action
• Minimal overlapping toxicities

These guidelines help optimize treatment efficacy and reduce side effects.

Question 13

What is the therapeutic use of Vincristine?

Answer 13

• Hodgkins Lymphoma
• Non-Hodgkins Lymphoma
• Lymphocytic Leukemia
• Wilms Tumor
• Breast Cancer
• Bladder Cancer

Vincristine is used in various hematological and solid tumors.

Question 14

What is the importance of pain management in cancer treatment?

Answer 14

To improve quality of life and manage cancer pain effectively

Appropriate pain management is crucial for patient comfort and treatment adherence.

Question 15

What are neutropenic precautions?

Answer 15

• Wash hands often
• Bathe daily
• Brush teeth twice daily
• Prevent constipation
• Avoid sharing personal items
• Avoid fresh flowers and standing water

These precautions help protect immunocompromised patients from infections.