Prostate

Question 1

Epidemiology

Answer 1

23% of all male cancers
5 years survival (at least)
2nd most common cause of death out of all male cancers

Question 2

Aetiology

Answer 2

Family
age
HBOC syndrome
agent orange exposure

Question 3

Diagnostic methods

Answer 3

PSA - prostate specific antigen. Not very conclusive
PSMA- Prostate specific membrane antigen. Protein produced in prostate, found freely in the blood • Higher than “Normal” level (age related) correlates with the presence of prostate cancer
DRE - Digital Rectal exam
Biopsy - TRUS (transrectal ultrasound scan) biopsy. Most reliable
Multiparametric MRI - for staging
Transperineal guided biopsy

Question 4

Patterns of Spread

Answer 4

Multifocal - slow growing but metastatic
Extend out of gland - spread to seminal vesicles, neck of bladder, rectum, invasion of lymphatics and blood vessels
Highest incidence of met spread - bone
Also spreads to liver, brain, lung

Question 5

Histology

Answer 5

Adenocarcinoma most common

also, transitional cell, sarcoma, SCC

Question 6

Staging

Answer 6

Gleason score for staging - depends on how much it looks like healthy tissue (how differentiated it is)
Grade group can be converted to gleasons score, larger grade group -> higher gleason score-> worse prognosis

Question 7

RT treatment technique advantage

Answer 7

prostate is retained, lower sexual dysfunction

Question 8

RT treatment disadvantage

Answer 8

High dose required due to low alpha/beta ratio

Question 9

Preparation for RT

Answer 9

full bladder (1hr before sim 500mL), empty rectum

Question 10

Scan parameters for Prostate patient

Answer 10

scan L3/L4 to 1.5cm below inf border of ischial tuberosities. Superior border will be extended when nodes are involved L1/L2. 2-5mm slices

Question 11

Room preparation

Answer 11

headrest, knee bolster, vacbag, foot-stocks

Question 12

Clinical management options

Answer 12

• Watchful waiting: no treatment, active surveillance - repeat PSA every 6 months, complication - could miss curable disease period
• Surgery - radical prostatectomy, complication - operative mortality, urinary symptoms, impotence
• hormone therapy - oestrogen therapy, androgen deprivation (inhibit growth of prostate cancer), orchiectomy (removal of testicles), complications: impotence and general feminisation
• Ultrasound (HIFU)
• Cryotherapy: freezing cancer cells, not enough info on long term effectiveness and not recommended for men with large prostates
  Radiation therapy: brachytherapy (LDR/HDR), external beam, proton therapy

Question 13

OARs for prostate and tolerances

Answer 13

Rectum (V50<50%)
Bladder (V65<50%)
Femoral Heads (V45<60%)
Penile bulb (mean dose <52.5Gy)
Small bowel (minimise dose)

Question 14

2 types of brachy

Answer 14

1. Low dose rate - seeds, monotherapy for low intermediate risk patients, as a boost to EBRT
2. High dose rate - needles, monotherapy for low-intermediate risk patients, as a boost combined with EBRT, done after failed EBRT with isolated local recurrence

Question 15

Acute RT side effects

Answer 15

tiredness, bladder irritation, frequency and urgency.

Question 16

Late RT side effects

Answer 16

urinary incontinence, radiation proctitis, erectile impotence

Question 17

Management of Acute side effects

Answer 17

tiredness - routine screen for fatigue, manage underlying causes
bladder irritation - anti inflammatory medication, frequency and urgency- alpha blockers
Rectum irritation - managed with dietary modification

Question 18

Management of late side effects

Answer 18

• urinary incontinence - prescribe alpha blockers
• radiation proctitis- referral to gastroenterologist
• erectile impotence- sexual counselling

Question 19

Signs and symptoms of Prostate cancer

Answer 19

Urinary changes, dysuria, haematuria. Frequency and urgency difficulty maintaining bladder volume
Mets: Bone pain, weight loss, testicular pain

Question 20

RT dose fractions

Answer 20

EBRT post radical prostatectomy - 64-66Gy in 32-33#
Definitive EBRT low risk - 73.8-74Gy/37.4#
Definitive EBRT intermediate/high risk- 78-81Gy/39-45#

Question 21

Spare OAR

Answer 21

hydrogel that is injected in between prostate and rectum to create barrier between them and decrease dose to rectums, dissolvable

Question 22

proton therapy

Answer 22

Protons are used in place of x rays - Protons do not exit tumour -> does not pass into healthy tissue (no exit dose) - Reduced radiation exposure and damage to healthy tissue - Effective in sensitive areas (e.g., brain, eye, spinal cord, heart, blood vessels)”