Prostate Cancer

Question 1

Summarise the epidemiology of prostate cancer

Answer 1

Most common male-specific cancer in the West
Affects 1 in 8 British men
Prevalence of prostate cancer increases dramatically w/age

Question 2

What are 7 clinical features of prostate cancer?

Answer 2

Enlarged prostate on DRE
Urinary retention, frequency, hesitation
Nocturia
Impotence
Back pain
Haematuria
[PSA] > 4ng/ml

Question 3

What methods are used to diagnose and monitor prostate cancer?

Answer 3

Positive PSA > 4ng/ml
Positive DRE: enlarged prostate
Prostate biopsy
Gleason scoring to grade

Question 4

What are the different therapies used to treat prostate cancer?

Answer 4

Active observation if tumour may remain latent for rest of patient’s lifespan
Radical prostatectomy if tumour confined to prostate gland
External beam radiotherapy if tumour has spread outside prostate capsule but not to other organs
Brachytherapy if tumour contained in prostate (radioactive seeds implanted in prostate)
Hormone therapy: bilateral orchidectomy + LHRH analogue + anti-androgens

Question 5

What is the purpose of each component of hormone therapy in treatment of prostate cancer?

Answer 5

Bilateral orchidectomy: removes main source of testosterone, mainly achieved through use of LHRH analogue
LHRH analogue overstimulates anterior pituitary, causing desensitisation so LH production ceases
Anti-androgens prevent adrenal androgen production

Question 6

What may permit relapse of prostate cancer with an androgen independent nature?

Answer 6

Amplification of response to low residual levels of androgen
Decreased levels of co-repressors
Mutation of androgen receptor, thus the anti-androgen is ineffective in blocking it