Radiotherapy

Question 1

Describe the role of radiotherapy

Answer 1

Half of cancer patients have radiotherapy

• curative
• palliative

Can be the

• only treatment
• main treatment with chemo
• part of multimodality treatment with surgery and systemic therapy
• reduce recurrence
• preop

Question 2

How does radiotherapy work

-what is the therapeutic ratio

Answer 2

Ionising radiation => delivered in targeted way to cause a double strand break

Therapeutic ratio - balance between tumour control and complications of radiotherapy

Question 3

Types of radiotherapy

Answer 3

Brachytherapy (internal RT) - radioactive seeds inserted temporarily into body

Radioactive isotopes (swallow radioactive tablet)

Ext beam

Question 4

Properties of radiotherapy compared to surgery and chemo

Answer 4

Surgery

• organ preservation
• no operative risk

Chemo

• no significant hematological toxicity, infection risk (neutropenic sepsis)
• can be given in renal/hepatic insufficiency

LOCAL TREATMENT

Question 5

How can you use radiotherapy palliatively

Answer 5

Aim to relieve symptoms
Minimum toxicity
Low dose, short course, simple approach

Oncological emergencies if surgery not possible
-SC, cauda equina compression

Bone mets => prevent fracture, pain control
Brain mets - chemo does not pass BBB easily

Organ compression/airway obstruction, pain from large masses

Question 6

How can you use radiotherapy radically

Answer 6

Aim to cure tumour
Some morbidity acceptable
High dose, long course, complex approach

Early tumours can be curable with radio alone
Can be part of multimodality treatment

Question 7

What are the acute SE

Answer 7

ONLY LIMITED TO IRRADIATED TISSUE
General
-fatigue, skin reaction

Brain

• N+V
• fatigue

H+N

• hairloss
• mucositis

Chest

• esophagitis, pneumonitis
• rib, chest wall tenderness

Abdo
-N+V+D

Pelvis

• diarrhoea
• cystitis

Question 8

What are the late SE (decades after treatment)

Answer 8

ONLY LIMITED TO IRRADIATED TISSUES
General
-2nd malignancy

Brain
-cognitive, memory problems

H+N

• dry mouth, eyes
• cataracts
• dental problems, mandible necrosis
• hypothyroidism

Chest

• lung fibrosis
• heart problems (ischemic, myocardial function, pericarditis

Abdo

• intestinal irritability
• kidney, liver damage

Pelvis

• proctitis
• impotence, infertility, menopause
• vaginal dryness

Question 9

How would you manage a patient during and immediately after RT

Answer 9

Weekly review
Preventative measures
-skin care advice - gentle washing
-antiemetics (prochlorperazine)
-oral hygiene 
-dietary review - radiotherapy plan is specific to their current body shape and weight

Symptomatic treatment

• loperamide - diarrhoea
• analgesia
• nutritional support
• skin reaction treatment
• rest from treatment

Question 10

How would you manage a patient in the long term after RT

Answer 10

Follow up for late effects

• screening for new cancers
• treatment for any lost function (thyroxine replacement for thyroid cancer)