Module 3 - Chapter 10 - Radiation

Question 1

What is radiotherapy used for?

Answer 1

used to kill cancer while minimizing damage to normal structures

Question 2

What does ionizing radiation do?

Answer 2

damages cells by imparting enough energy to cause molecular damage especially to DNA

Question 3

List the severity of radiation damage?

Answer 3

1. Lethal - kills cell
2. Potentially lethal - cell is so severely affected by radiation that modifications in its environment will cause it to die;
3. Sublethal - cell can subsequently repair itself

Question 4

What is required for effective cell killing by radiation

Answer 4

good local delivery of oxygen, something not always present in large cancers.

Question 5

What can results from radiation?

Answer 5

Radiation produces slow changes in most cancers and irreversible changes in normal tissues as well.

Question 6

Why does each tissue have a maximum lifetime dose of radiation it can tolerate?

Answer 6

Because of the irreversible changes in the normal tissues

Question 7

Give examples of radiation delivery methods

Answer 7

1. External Beam
2. Brachytherapy - I-labelled capsules (also called seeds) - temporarily placed into body cavities

Question 8

Brachytherapy is useful for which types of cancer.

Answer 8

cervical, prostate, and head and neck cancers.