How Do Doctors Test for Prostate Cancer?

As prostate cancer is the 3^rd most common cancer in Singaporean men, it's important to go for regular screening even if you have no symptoms.

The PSA test may sound complicated, but it's actually a very simple blood test. If you're male and over the age of 50, here's why you should go and get it done.

PSA tests help to detect prostate cancer early

People with prostate cancer may experience a range of symptoms, such as a frequent urge to urinate, bleeding when urinating and difficulty in passing urine. However, many people with prostate cancer have no symptoms at all.

Your prostate gland naturally produces PSA, a protein, and its levels are often higher in people with prostate cancer. Therefore, it makes sense that the PSA test functions as a cancer marker by measuring the levels of PSA in your blood.

"If your test comes back with a reading higher than 4.0 nmol/dL, your doctor may recommend you undergo further investigations such as an MRI scan of the prostate or a prostate biopsy (tissue sample) to check for additional signs of cancer," says Dr Ho. "Don't panic, though, as certain non-cancerous conditions can also cause your PSA levels to rise, such as prostatitis (inflamed prostate) and benign prostatic hyperplasia (enlarged prostate). Your doctor will also be looking for indicators of these."

If your doctor performs the prostate biopsy and detects cancer, they will be able to categorise you into 1 of 4 groups:

• Very low risk: Observation only, no treatment is required
• Low risk: Observation only, surgery or radiation treatment can be considered
• Intermediate risk: Surgery or radiation treatment required
• High risk: Surgery or radiation treatment required

PSA tests don't need special preparation

In a PSA test, your doctor will simply take a small blood sample from your arm and send it away for testing. You won't need to do anything in advance – you can just turn up on the day. Often, your doctor will be able to share the results with you after just 24 hours.

PSA testing is the first step in diagnosing and treating cancer

In the past, some people have labelled PSA tests as controversial. That's because the results from a PSA test alone are usually not enough to confirm a cancer diagnosis and, without further testing, could result in unnecessary anxiety.

High levels of PSA can be caused by other benign prostate conditions, like the ones listed above. But as medicine continues to advance, doctors are now able to use several different methods to reach the right diagnosis and prescribe treatment accordingly.

The multi-parametric MRI scan is one such diagnostic tool. It detects suspicious areas in the prostate by looking for structural and functional changes in the prostate cells, based on the fact that cancer cells are aggressive and rapidly dividing. Following the scan, you will be given a score called PI-RADS which ranks the probability of cancer from 1 to 5. Scores of 1 and 2 refer to a low probability of cancer while scores of 4 and 5 means you have an 80% and 90% chance of cancer.

The MRI-ultrasound fusion prostate biopsy is another tool that has been available in Singapore for the past 2 years. In a traditional prostate biopsy, your doctor takes tissue samples at random, which could mean cancerous cells are overlooked the first time. But in a MRI-ultrasound fusion biopsy, your doctor takes a much more targeted approach.

"The procedure starts with an MRI scan, which is a magnetic scanner that uses radio waves to take images of your internal organs and display them on a computer screen," explains Dr Ho. "Your doctor can use this check for suspicious-looking areas. Then they will insert a thin, flexible ultrasound device into your rectum, using the MRI images to guide them to the suspicious-looking area so they can snip a small tissue sample."

Another advanced diagnostic tool is the prostate specific membrane antigen (PSMA) positron emission tomography (PET) scan, which sounds like a mouthful but is an accurate method for your doctor to detect recurring prostate cancer. Your doctor may also recommend you have this scan to check whether cancer has spread anywhere else in your body.

When it comes to treatments, you may be able to have a robotic-assisted radical prostatectomy (minimally invasive surgery to remove the prostate) instead of traditional surgery, as it can help to reduce recovery time as well as the risks of complications while you're under anaesthetic.

Experts recommend annual PSA testing for older men

"As most prostate cancers occur in men over the age of 65, the American Urological Association, Society of Urologic Oncology and American Society of Radiation Oncology all agree that men between the ages of 50 and 70 should go for a PSA test once a year," clarifies Dr Ho. "Men with a family history of prostate cancer should start going annually from the age of 40."

If you need to arrange for a PSA test, make an appointment with a specialist.