Prostate cancer is the most common lethal malignancy in men in Australia. It does not have one single cause, with multiple genetic abnormalities and a requirement for the male hormone testosterone, which serves as “food” for the cancer. Men with a family history of prostate cancer have an increased risk. Rarely-inherited conditions also significantly increase risk (e.g. BRCA gene mutations).
Early cancer has NO symptoms. As a result, frequent health examinations are the best defence against prostate cancer.
Urinary symptoms (frequency, urgency of urination, getting up to urinate overnight, dribbling, poor stream etc) are usually not related to early stage prostate cancer.
Advanced disease (once cancer has spread from the prostate to bones or other organs) can present with pain in the pelvis or bones, weight loss, urinary or other symptoms.
The PSA (prostate specific antigen) blood test is used for screening for prostate cancer. Most men with prostate cancer have an elevated PSA; however, other conditions such as benign enlargement of the prostate or inflammation or infection of the prostate can also cause elevated PSA levels. Some men can have “normal” PSA levels and have cancer. PSA, therefore, is NOT a “Yes or No” test.
Digital Rectal Examination
Digital rectal examination (DRE) is an examination of the prostate by the Urologist where a gloved and lubricated finger is inserted into the back passage (rectum) in order to assess the size and consistency of the prostate. If to a specialist’s examination the prostate feels abnormal (irregular and/or hard), then further investigations may be warranted.
The age and general health of the man is important to consider before any further investigation. In some men there may not be a benefit in further investigation.
MRI of the prostate can be useful for further investigation of men with elevated PSA. It uses a powerful magnet to image the prostate (no radiation) and may identify areas of suspicion to target on biopsy or indicate no abnormalities and potentially avoid an unnecessary biopsy. It is not 100% foolproof however, and in some circumstances, biopsy would still be recommended despite having a “normal” MRI.
A prostate biopsy is a common and safe procedure and is required to diagnose prostate cancer. It is performed under sedation or a general anaesthetic in the operating theatre.
An ultrasound probe in the back passage guides the biopsy of the prostate with needles either through the back passage (transrectal) or through the skin under the scrotum in front of the back passage (transperineal). Computer software may be used in conjunction with MRI images to target specific areas of the prostate (fusion biopsy).
The tissue is examined by a pathologist under the microscope and they determine if cancer is present, where it is, how much there is and what grade it is.
Common Side Effects
- Blood in the bowel movement for a day or two
- Blood in the urine
- Blood in the ejaculate – which is bright red at first and then becomes a rusty colour and can take a couple of months to clear
- Bruising of the perineum and scrotum if a transperineal biopsy is performed
Rare Side Effects
Difficulty urinating due to swelling of the prostate which may require a temporary catheter for a day or two (more common in transperineal biopsy and in men with pre-existing urination difficulty, <10% risk)
Infection of the blood stream – this is extremely rare in transperineal biopsy (<1:1000) but can occur in 2-3% of men undergoing transrectal biopsy. Any man with fevers, shivers and shakes, or feeling unwell following a biopsy should immediately contact A/Prof Vela for advice and/or present to their nearest hospital emergency department for intravenous antibiotics.
Prostate Cancer Grading
Prostate cancer is graded using various systems. The traditional grading system is the Gleason Grading system with two numbers given adding up to a score of 6 -10. This is determined by the pattern of cancer the pathologist sees in the biopsy specimen. Low grade cancer is any numbers adding to 6, intermediate cancer is any numbers adding to 7 and high risk cancer is anything adding up to 8 -10. This system is quite confusing for patients so a new simplified grading system has been developed call the ISUP Grade Group. This new system uses the Gleason score as its backbone but reports the cancer on a scale of 1-5 with increased cancer aggressiveness with higher numbers.
- ISUP GG 1 = old Gleason 3+3=6 = low risk cancer
- ISUP GG 2 = old Gleason 3+4=7 = low intermediate risk cancer
- ISUP GG 3= old Gleason 4+3=7 = high intermediate risk cancer
- IUSP GG 4 = old Gleason any combination = 8 = high risk cancer
- ISUP GG 5 = old Gleason any combination = 9 or 10 = very high risk cancer
An important part of the workup following a diagnosis of prostate cancer is “staging”. This involves tests which may indicate if the cancer has spread from the prostate to other parts of the body (metastasis) or if it remains localised to the prostate.
Imaging scans such as CT scans, Bone scans, or PSMA PET CT scans may be utilised to assess this dependent on the grade of cancer. These staging scans will often determine which of the various treatment options are recommended by A/Prof Vela in your individual case.
Dependent on the treatment option selected, follow-up or “surveillance” varies slightly.
With surgery, the PSA test becomes the mainstay of surveillance. If the PSA remains undetectable, the patient is “cured”. With the current super sensitive PSA tests this is a very early warning system. If a detectable PSA is measured various options exist including continued surveillance, salvage radiation therapy or possibly other medical therapies such as androgen deprivation therapy (ADT) or chemotherapy.
With radiation therapy, PSA is also the mainstay of follow-up however is a little more complicated due to the fact that PSA is continued to be excreted from the prostate. Levels can rise and fall as cells die from treatment, causing a “PSA bounce”. This can sometimes be anxiety provoking for patients as levels rise, but the significance can be determined by specific levels.
Sometimes repeat imaging (re-staging) scans may be recommended. Currently PSMA PET CT scans are the most sensitive scans available and are the preferred option in many situations.
With watchful waiting and systemic therapy, PSA is also the main surveillance test along with other bloods tests, however more routine intermittent imaging may be also recommended.