The diagnosis and management of prostate cancer is a challenging, complex and in some aspects a controversial field. What follows is an overview of the disease and its management from my perspective. I would encourage those interested to click on the links below to learn more about the disease.
What is the prostate?
The prostate is a gland located at the base of the bladder. It produces fluid that mixes with sperm from the testes to form the ejaculate. Urine exits the bladder through the prostate so diseases of the prostate can affect the way in which men urinate.
What is prostate cancer?
Prostate cancer is when the normal cells that make up the prostate change and multiply independently of the bodies normal control mechanisms. These cancerous cells have the potential to grow beyond the normal confines of the prostate and in some cases can spread to other parts of the body.
Prostate cancers are very variable and many men will have completely different experiences with the disease. Many prostate cancers are slow growing and behave in an indolent manner where others are aggressive and spread relatively rapidly. Knowing which is which is the greatest challenge confronting Urologists and associated prostate cancer specialists.
How common is prostate cancer?
Prostate cancer is the most common cancer in Australian men (aside from non melanoma skin cancers). Each year around 23,000 Australian men are diagnosed and approximately 3,300 men die from prostate cancer. It is the second leading cause of cancer death in men and the fifth highest overall cause of death in men.
What are the risk factors for developing prostate cancer?
Age is the strongest risk factor with the incidence of prostate cancer increasing as men get older. Another important risk factor is a family (father or brother) history of prostate cancer.
How is prostate cancer diagnosed?
Early prostate cancer has no symptoms. Most men are diagnosed after a prostate specific antigen (PSA) blood test and or a digital rectal exam (DRE) reveals abnormalities. If the PSA or DRE is abnormal then a prostate biopsy may be recommended.
PSA blood test
PSA (Prostate Specific Antigen) is a chemical produced by the prostate that helps liquefy the semen. A small amount of PSA normally enters the blood stream and can be detected by a serum PSA blood test. Several conditions can result in a significant elevation in PSA levels, these include:
- Prostate cancer
- Benign prostatic hyperplasia (BPH)
- Prostatitis (inflammation of the prostate)
The normal upper limits for normal serum PSA vary between laboratories and with age, in general they are:
- Age 40-49 2.5ng/ml
- Age 50-59 3.5ng/ml
- Age 60-69 4.5ng/ml
- Age 70-79 6.5ng/ml
If an initial PSA test is elevated a repeat test will be performed to confirm its level.
If the PSA is persistently elevated above the normal range then a prostate biopsy may be recommended. If the PSA is elevated above the normal range but below 10ng/ml then the chance of having prostate cancer diagnosed on biopsy is approximately 30%. The risk increases significantly as the PSA rises over 10ng/ml.
PSA is not a perfect test for prostate cancer as it may be elevated by non-cancerous conditions. Prostate cancer may also be present even if the PSA is within the normal range.
Digital rectal examination (DRE)
This is an examination in which the doctor inserts a lubricated, gloved finger into the anus and feels the surface of the prostate. The firmness, contour and symmetry of the prostate gland is assessed. The examination may evoke anxiety and cause some discomfort but is rarely painful.
If the prostate feels suspicious for cancer then a prostate biopsy may be recommended even if the PSA is normal. If the PSA is normal but the DRE is suspicious then the chance of finding cancer on biopsy is around 15-20%. If the PSA is elevated above the normal range but below 10ng/ml and the DRE is suspicious then the chance of finding cancer on biopsy is around 45-50%.
A prostate biopsy may be recommended when the PSA is elevated and or the DRE is suspicious for cancer. A prostate biopsy is a day procedure carried out in hospital under sedation. An ultrasound probe is inserted into the rectum and the prostate gland is imaged. Multiple biopsies are then taken from various segments of the prostate under ultrasound guidance. The procedure takes on average 15 minutes and patients are discharged 2-3 hours later.
In certain circumstances a trans-perineal prostate biopsy may be recommended. This procedure differs from a traditional transrectal ultrasound guided prostate biopsy in that the needle is inserted through the skin between the anus and scrotum instead of through the rectal wall. This procedure is done under a general anaesthetic.
The biopsy results will be discussed at the follow up consultation one to two weeks after the procedure. If the biopsy did not show cancer then further follow up with PSA tests will be arranged. If the biopsy did show cancer then the treatment options will be discussed and further radiological tests may be ordered.
Prostate cancer treatment
Many factors are taken into account when deciding treatment options for prostate cancer. Some important factors include: age and co-existing medical conditions, PSA level, grade of cancer and whether the cancer has spread outside of the prostate. There are many ways in which prostate cancer can be treated and the final choice may take some time to reach. In general treatment options may include:
- Active surveillance
- Ablative and focal therapies
- Watchful waiting
This form of treatment is reserved for the lowest risk prostate cancers. Immediate treatment of the prostate cancer is withheld and the disease is then carefully monitored over time. If during surveillance it becomes apparent the cancer is behaving in a more aggressive manner than definitive treatment aimed at curing the disease is instigated. Active surveillance aims to avoid the side effects associated with prostate cancer treatment whilst maintaining the ability to cure the disease should it develop more aggressive features.
Surgery to remove the prostate (radical prostatectomy) is a treatment option for men diagnosed with localized prostate cancer (ie no spread of cancer). There are several techniques available all of which have different pros and cons. Further information about prostate cancer surgery can be found in the procedures section under radical prostatectomy.
Surgery to open up the internal portion of the prostate may be required if the cancer has blocked the outlet of the bladder or causes problematic bleeding. This surgery is called a Transurethral Resection of Prostate (TURP). This type of surgery aims to alleviate bothersome symptoms but does not cure prostate cancer.
Radiotherapy is a treatment option for men diagnosed with localized prostate cancer. In general there are two forms of prostate radiotherapy: external beam radiotherapy (EBRT) and brachytherapy.
EBRT is where radiotherapy beams are directed at the prostate and is designed to kill the cancerous cells. The treatment is given once a day for 7-8 weeks. EBRT is given under the care of a specialist doctor called a radiation oncologist. EBRT may also be directed at bones if the prostate cancer has spread and causes pain to these areas.
Brachytherapy is when radioactive seeds or rods are inserted directly into the prostate. Radiation is then emitted from these seeds or rods and is designed to kill the cancerous cells. Brachytherapy treatment requires a short hospital stay.
Ablative and focal therapies
There are two forms of ablative prostate cancer treatment High Intensity Focused Ultrasound (HIFU) and cryoablation. HIFU is where a probe is inserted into the rectum and ultrasound waves are focused onto the prostate. The prostate tissue is heated with the aim of killing the prostate cells. Cryoablation is where rods are inserted into the prostate. The rods are cooled and the prostate is frozen again with the aim of killing the prostate cells.
Focal therapies are a relatively new form of treatment for prostate cancer. Focal therapies aim to kill the cancer within the prostate whilst leaving the adjacent tissue intact and functional. There are many concerns regarding the safety and efficacy of this treatment option. The Urological Society of Australia and New Zealand has released a position statement on focal therapies, for more information please follow the link (USANZ Position Statement on Focal Therapy for Prostate cancer).
Ablative and focal therapies are relatively uncommon forms of prostate cancer treatment. In my opinion there is lack of rigorous scientific data to support their safety and efficacy. For this reason I do not offer ablative or focal therapies for prostate cancer treatment, if however a patient is interested then referral will be made to an alternate Urologist.
This form of treatment is usually reserved for elderly patients with a life expectancy of less than 5-10 years. This is where the prostate cancer is monitored and hormonal treatment commenced if the disease becomes symptomatic or aggressive. This treatment does not cure prostate cancer but aims to control it symptoms.
To read more about the diagnosis and treatment of prostate cancer follow click on the links below.
- Prostate Cancer Diagnosis (Andrology Australia)
- Prostate Cancer Fact Sheet (USANZ)
- USANZ PSA testing policy 2009
- Localised Prostate Cancer Book 2010 (Cancer Council Australia)
- Advanced Prostate Cancer Guide 2009 (Cancer Council Australia)
- Prostate Cancer Treatment (Andrology Australia)
- What you need to know about prostate cancer (National Cancer Institute USA)
- Urology Care Foundation Prostate Cancer Patient Information (American Urological Association)
- USANZ Position Statement on Focal Therapy for Prostate cancer
- Cancer Council Australia
- Prostate Cancer Foundation of Australia