- Commonest malignancy of male urogenital tract
- Wide variation in different races
- Most common in northern Europe and North America
- Rare in far east Asia
- There are about 20,000 cases per year in the United Kingdom
- Rare before the age of 50 years
- Found at post-mortem in 50% of men older than 80 years
- 5-10% of operation for benign disease reveal unsuspected prostate
cancer
Pathology
- The tumours are adenocarcinomas
- Arise in the posterior part of the gland
- 70% arise in peripheral zone
- 20% originate in transition zone
- 10% are found in central zone
- Spread through capsule into perineural spaces, bladder neck, pelvic
wall and rectum
- Lymphatic spread is common
- Haematogenous spread occurs to axial skeleton
- Invasion into the seminal vesicles is associated with distant spread
- Tumours are graded by Gleeson classification
Clinical features
- Early low-grade disease is often asymptomatic
- 60% present with symptoms of bladder outflow obstruction
- 10% are incidental findings at TURP
- Remainder present with bone pain, cord compression or
leuco-erythroblastic anaemia
- Renal failure can occur due to bilateral ureteric obstruction
Diagnosis
- With locally advanced tumours diagnosis can be confirmed by rectal
examination
- Features include hard nodule or loss of central sulcus
- Transrectal ultrasound is useful in cases of diagnostic doubt
- Transrectal or transperineal biopsy should be performed
- Pelvic CT or MRI is useful in the staging of the disease
- Bone scanning will detect the presence of metastases
- Unlikely to be abnormal if asymptomatic and PSA < 10 ng/ml
Serum prostate specific antigen (PSA)
- Kallikrein-like protein produced by prostatic epithelial cells
- 4 ng/ml is the upper limit of normal
- Greater than 10 ng/ml is highly suggestive of prostatic carcinoma
- Can be significantly raised in BPH
- Useful marker for monitoring response to treatment
Treatment
- More men die with than from prostate cancer
- Treatment depends on stage of disease, patient's age and general
fitness
- Treatment options are for:
- Local disease
- Observation
- Radical radiotherapy
- Radical prostatectomy
- Locally advanced disease
- Radical radiotherapy
- Hormonal therapy
- Metastatic disease
Radical prostatectomy
- Removes the entire prostate gland
- Seminal vesicles are removed with the prostate glans
- Care is taken to preserve the peri-prostatic plexus of nerves
- Urethra is anastomosed to the base of the bladder
- Associated with
- Improvement in mean survival compared to simple observation
- 50% reduction in risk of metastatic disease
- Erectile dysfunction occurs in 50% patients
- 3% develop stress incontinence
Hormonal therapy
- 80% of prostate cancers are androgen dependent for their growth
- Hormonal therapy involves androgen depletion
- Produces good palliation until tumours 'escape' from hormonal
control
- Androgen depletion can be achieved by:
- Bilateral subcapsular orchidectomy
- LHRH agonists - goseraline
- Anti-androgens - cyproterone acetate, flutamide
- Oestrogens - stilbeostrol
- Complete androgen blockade
Bibliography
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Pisansky T M. External beam radiotherapy for localised prostate
cancer. N Engl J Med 2006; 355: 1583-1591.
Sandhu S S, Kaisary A V. Localised carcinoma of the
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Wilt T J, Thompson I M. Clinically localised prostate
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