Investigations and tests

This page provides information about the  investigations and tests that might be undertaken in connection with prostate disease and prostate cancer.  

PSA blood test (prostate specific antigen)

What is PSA, the PSA test and what does it involve?

The prostate produces a protein called Prostate Specific Antigen (PSA). The role of PSA is to make semen more fluid and so help sperm swim more easily. Some PSA ‘leaks’ out of the prostate into the bloodstream; so, it’s normal for some PSA to be in your blood. Your GP will take a blood sample and send this to the laboratory to measure how much PSA is in your blood. You will hear this called your PSA level. If the prostate is damaged or is affected by prostate disease then the more PSA will escape from the prostate into the bloodstream so giving a higher PSA blood level.

Why might a PSA test be done?

The main reason is to check for things going wrong with the prostate such as Benign Prostatic Hyperplasia – BPH (sometimes this is called Benign Prostatic Enlargement – BPE), Prostatitis or to check for prostate cancer.

If you have been diagnosed with prostate disease or prostate cancer your doctor will use the PSA level as a check to make sure that treatment is working or if it needs to be changed

Why might the PSA level be raised?

The most usual causes are:

1. The prostate becoming inflamed known as Prostatitis
2.  The prostate growing bigger or enlarging, called Benign Prostatic Hyperplasia (BPH). You may also hear this called Benign Prostatic Enlargement (BPE)
3. A urinary tract infection
4. For 2 out of 3 men a raised PSA level will not mean prostate cancer. But for some men it can be a sign of having prostate cancer. However, a single PSA test may not definitely confirm whether you have prostate cancer or how quickly it is likely to grow. It is often done alongside other tests or examinations, e.g. Digital Rectal Examination (DRE)

What is the normal level for PSA?

To some extent this depends on your age. The older you get, the higher your PSA level is likely to be. The doctor who gets your PSA results will take this into account. In some areas there may be slight differences in the levels used and your doctor will explain this to you.

In January 2019, GPs were issued with updated ‘Urgent suspicion of cancer referral guidelines’.  The guidelines provide a rough guide to normal PSA levels (ng/ml) by age group.

• Age less than 60 years ~ less than 3.0 ng/ml
• Age 60–69 years ~ less than 4.0 ng/ml
• Age 70-79 years ~ less than 5.0 ng/ml

Even if your PSA level is within the normal range, if your GP has any concerns you may be asked to have your PSA level checked again.

The man’s PSA level is useful in helping doctors make a diagnosis. It can also be useful in monitoring treatment being given for benign prostate disease and prostate cancer.

For older men, routine or no referral may be appropriate (subject to clinical consideration) for PSA levels of:

• Age 80-85 years ~ more than 10ng/ml
• Age 86 years and over ~ more than 20ng/ml

About the PSA level

Your PSA level is not raised – In all probability no further action will be taken. You might find that you will be asked to have another PSA test to confirm the result at a later date especially if you are over 50 or have a brother or father who has/had prostate cancer.

Your PSA level is raised – You will need some further tests including more PSA tests and your doctor may want to do a DRE.

Your GP may refer you to a specialist for further tests such as a prostate biopsy to check for disease in the prostate. Once a diagnosis is made, you will be given lots of information in order that you and your doctor can decide on the type of treatment that is right for you.

Are there any times when I shouldn’t have the test done?

PSA levels can be affected by several things so may give a false high level of PSA in your blood. Let your doctor know if any of these apply to you and put off having the test:

• If you have an active or have had a recent urinary infection
• If you have ejaculated in the last 48 hours
• If you have exercised energetically in the last 48 hours
• If you have had a prostate biopsy in the last 6 weeks
• If you have had a DRE (Digital Rectal Examination) in the last week
• If you have had a prostate massage
• Tell your doctor about any medications or herbal remedies you are taking

Free PSA in your blood

PSA travels in the blood in two forms:

• Unattached to a protein in the blood called Free PSA
• Attached or bound to a protein in the blood called Bound PSA

The Free PSA test measures the proportion of unattached or Free PSA to the total amount of PSA in your blood sample. It is thought that a higher amount of free PSA in a test means a lower chance of having prostate cancer.

PSA doubling time

If you have been diagnosed with prostate cancer and decided to manage it by Active Surveillance, or you have had a radical prostatectomy or radiotherapy treatment your PSA will be checked regularly. A single, one-off rise in your PSA level may be due to other reasons, such as an infection. If your doctors notice that the level is continuing to go up, they will look at how quickly and by how much it has gone up.

If your PSA level doubles in less than 3 years (called your PSA doubling time) then, your doctor will discuss this with you as it may be a sign that your prostate cancer is becoming more aggressive.

If your PSA rises, even though it doesn’t actually double, it may be that your doctor advises that active surveillance is no longer a suitable management for your prostate cancer.

For further information about PSA testing see the leaflet The PSA Test, the booklet PSA Explained and page 14 of the booklet Early prostate cancer explained

DRE (digital rectal examination)

As the prostate cannot be seen or checked from outside the body, a DRE gives the GP, urologist or CNS an idea of the shape, size and condition of your prostate. The doctor checks for any hardened area, odd shape, unusual lump and the general condition of the prostate.

For this examination, you will be asked to lie on the bed on your side. The doctor or CNS will slide a lubricated, gloved finger into your back passage or rectum to feel your prostate. Although this may feel a bit uncomfortable, it shouldn’t hurt and it does not take very long to do. It’s much better for you and the doctor if you can manage to relax during the examination, even if you feel a bit embarrassed. Remember, the doctor has done this many times before and understands how you might be feeling.

What is a prostate biopsy?

It is a test that your consultant urologist, CNS (clinical nurse specialist) or GP may ask you to have done. It involves taking tiny samples of tissue from your prostate then looking very carefully at these under a microscope. There are 3 types of biopsy:

TRUS biopsy

The TRUS biopsy is a trans-rectal ultrasound and biopsy and is usually the standard way to have a biopsy if you have a raised PSA and/or the doctor has concerns when she/he examined your prostate. It involves taking tissue samples from your prostate through the wall of the back passage. Occasionally, the trans-perineal (reaching the prostate through the perineum, the skin between your scrotum and back passage) method can be used if there are difficulties reaching your prostate through the back passage.

To reduce the risk of infection, you may be asked to take antibiotic tablets immediately before the operation and you will most likely be given a small supply to take at home after the biopsy. In some hospitals you may be asked to have an enema to clear your bowel before the TRUS and biopsy.

A small ultrasound instrument, about the size of a thumb, coated with gel is gently passed into your back passage. The instrument works by releasing sound waves. The echoes from the sound waves give a clear picture of the shape and size of your prostate that the doctor or CNS can see on a screen.

An injection of anaesthetic is given to numb your prostate. A very fine needle is used to take around 10 tiny samples of tissue from targeted areas in your prostate.

The whole procedure takes about 15 minutes but taking the samples only takes a matter of seconds.

Before you go home, you will be asked to pass urine to make sure that you can pass urine and that it’s not too blood stained. After the biopsy you may find; blood in your urine but this should clear up in about a week, blood in your semen for about 4-6 weeks, blood when you pass a motion, a dull ache in the area between your scrotum and back passage.

Template guided prostate biopsy (or trans-perineal biopsy)

Again Template guided prostate biopsy, is to take tiny samples of prostate tissue but the prostate is reached in a completely different way. This may be biopsy of choice when the cancer is thought to be at the front of the prostate or the prostate cannot be reached through the back passage.

It involves placing a special grid (or template) against your perineum (the skin between your scrotum and back passage) and taking tissue samples from your prostate through the perineum. In order to take samples from all areas of the prostate, the grid has holes every 5mm. The very fine biopsy needles are pushed into the prostate through the holes and samples of tissue are taken very quickly in a regular, organised way throughout the grid.

Usually about 30–50 samples are taken and the clinician/CNS doing the biopsy can choose the areas to target. Once all the samples have been taken, the grid is taken away and a firm dressing is applied and a pair of disposable pants will help keep this in place.

As this is a surgical procedure, you will either have a general anaesthetic (you will be asleep) or a spinal anaesthetic (you will be numb from the waist down).

After the biopsy you may find; blood in your urine for up to 10 day, blood in your semen for up to 6 weeks, bruising of the skin and perineum, temporary discomfort in back passage or soreness in back passage area, on a few occasions, swelling can occur in the prostate which can lead to difficulties in passing urine or very occasionally not able to pass urine at all.

MRI fusion guided biopsy

The MRI fusion guided biopsy uses the same procedures as outlined above. In addition, this type of biopsy also involves overlaying (or fusing) a recently taken MRI (MRI means magnetic resonance imaging. An MRI scan uses magnets rather than x-rays to produce detailed pictures of your prostate.) high definition picture onto the live images on screen from the ultra sound scan.

Once the two types of specialist diagnostic techniques are fused together by special computer software, they provide a detailed 360°, 3D picture of the man’s prostate. The advantage of MRI fusion guided biopsy being the biopsy needle can be very accurately targeted to specific areas in the prostate.

Infection

After biopsy, a small number of men may be at risk of developing an infection. This is why it’s really important to take all your antibiotic tablets, as directed by the doctor or CNS, if you have been given these.

As the needles for a template guided prostate biopsy go through the skin of the perineum, there may be a slightly lower risk of infection rather than with a TRUS biopsy where the needles pass through the wall of the back passage.

However, after either biopsy if you start to pass a large number of blood clots, can’t pass urine at all, have a burning feeling when passing urine, are in severe pain or develop a high temperature over 38°C, feel hot, cold and shivery, then you should contact your GP or NHS 24 straight away. If you have been given a particular number to call by hospital staff, then you should call that number.

How long before I get the results?

The results will go to your consultant or GP in about 2-3 weeks’ time. This may vary from area to area so ask the doctor or nurse who did the biopsy when you are likely to get your results. If you don’t hear after 3 weeks, there’s no harm phoning the CNS at the hospital to ask about your results. In some hospitals, the doctor or CNS will phone and give you the biopsy results. After getting the results, you will most likely be given an appointment to see the consultant at the hospital.

Bone Scan

A bone scan might be suggested if the urologist/oncologist needs to check if the cancer has spread outside the prostate and into the bones. However, if your PSA level was low and the doctor said your cancer was low-risk, you may not have a bone scan.

What happens?

This test is done in hospital and you will probably be asked to go into the department a few hours before your scan is due. There, a tiny amount of a radioactive material is injected into a vein in your arm, possibly making you feel a bit hot or flushed for a minute or two. Your scan will take place a few hours later because the radioactive material is slowly taken into your bones. After this injection you may be able to leave the department, and come back in a few hours but always check this with the department you are attending.

Before the scan, you will possibly be asked to empty your bladder then you will be taken to a scanning room. Staff may ask you to take off any metal jewellery or metal fasteners. You will be asked to lie down on a narrow bed and will need to lie still in the same position, for about 15-20 minutes. Your whole body will be scanned by a special camera for any ‘hot spots’. Hot spots are areas that take up a lot of the radioactive material and this may point to a tumour being there. It’s worth telling the doctor or radiographer about old fractures or arthritic changes as these show up as hot spots.

As the radioactive material doesn’t cause any side-effects, you will be able to go home afterwards. You may be advised to drink plenty of fluids to help get rid of the small amount of radioactive material still in your body.

It may be wise not to be in close contact with pregnant women, babies or young children until the day after the scan. Ask for more advice on this at your bone scan.

At the same appointment as your bone scan, you may be advised to have a normal x-ray or CT scan to check for any wear and tear in the bones and joints.

What about the results?

You won’t get the results right away and it may take a few weeks before you hear. A doctor who specialises in studying scans will look at your bone scan in detail and send a report to the doctor who referred you for the bone scan. Ask who you should contact and when you are likely to hear about the results.

CT scan (computerised tomography)

A CT scan combines special x-ray equipment with advanced computers to take many pictures in lots of different views inside your body. These pictures can be studied on a computer screen, printed out or transferred to a CD.

Why is it done?

It can show if the cancer has spread outside the prostate to the lymph nodes or the area around your prostate.

What happens?

A special dye is injected into a vein, probably in your arm, to help make the pictures clearer. This might make you feel hot for a few minutes. You will be asked to lie flat on your back on a narrow table and keep quite still as any movement may blur the picture.

At first, the table will move quickly through the scanner, then, more slowly as the CT scan is done. You might hear slight buzzing, clicking and whirring sounds as the CT scanner turns around you as the pictures are taken. Although the radiographer isn’t able to stay in the room they can see, hear and speak to you all the time during the CT scan.

When the CT test has been completed, you will probably have to wait to make sure that the pictures are good quality so the doctor has sharp images to see what is happening in your body.

A CT scan usually takes about 30 minutes and most men will be able to go home after the scan. You will probably get the results back in about 1-2 weeks. Ask how long it might take for your results to come back and if you have to phone to get them.

Cystoscopy

This is usually done in the day bed area in hospital or in an outpatient area of the hospital so you shouldn’t need to stay overnight. Some people are given a sedative to help them relax whilst the examination is done.

Some ‘jelly’ with an anaesthetic in it is squeezed into the urethra (the tube that takes urine out of the bladder). This helps to reduce any discomfort.

The doctor gently passes a small, flexible tube (called a cystoscope) which has a camera on the end into your urethra up through your penis. This is to examine your bladder and your urethra. As it shows up on a screen you may be able to see inside your bladder if you want to! The whole thing should only take between 5 – 10 minutes.

Then the doctor will gently pull the cystoscope out. Afterwards, you may feel a bit sore or have a burning feeling when you pass urine. You may need to pass urine more often or you may see a little blood in your urine, but this should stop after a few days. If it doesn’t or you find it difficult to pass urine, contact the clinic or your GP.

MRI scan (magnetic resonance imaging)

What is this?

An MRI scan uses magnets rather than x-rays to produce detailed pictures of your prostate, surrounding tissues, bones and other organs. The pictures can be viewed on a computer screen. The machine is like a long tunnel which covers most of your body.

Why is this done?

Usually, this is done after a prostate biopsy has found cancer in the prostate. In some centres, patients may be asked to have an MRI scan before their biopsy. An MRI scan is used to look closely at the cancer in the prostate. The pictures can also show if the cancer has remained within the prostate or has spread outside the walls of the prostate to other organs or tissues. It will help the doctor decide on the treatment choices most suitable for you.

What happens?

It is probably best to wear comfortable, loose-fitting clothing without metal fasteners and take off any jewellery or other metal objects before going in for the scan.

You will most likely be asked questions about your health and if you have any metal implants such as a pacemaker and usually the doctor or radiographer will go through a checklist with you, asking about metal implants to make absolutely sure the scan will not harm you in any way. Let the staff know if you don’t like being in or have a fear of closed spaces or are unable to undergo an MRI scan for any other reasons.

You will be asked to lie flat on your back on a narrow table and asked to keep quite still. Pillows and supports might be used to help you stay still and in the correct position. The table slides into the tunnel and you may find that the machine is quite noisy. At certain points, the radiographer may ask you to hold your breath or lie totally still while the images are being recorded.

The radiographer isn’t able to stay in the room, but can see, hear and speak to you all the time during the MRI scan. The scan usually takes between 30 and 40 minutes. When it’s finished, you will probably have to wait to make sure that the pictures are good quality so the doctor has sharp images to see what is happening in your body.

You won’t get the results straight away, so ask when you are likely to hear about the results of the scan. You should feel free to contact the hospital to ask about your results.

Prostate massage

For this examination, you will be asked to lie on the bed on your side. The doctor or CNS will slide a lubricated, gloved finger into your back passage or rectum to massage your prostate. Although this may feel a bit uncomfortable, it shouldn’t hurt.. It’s much better for you and the doctor if you can manage to relax during the examination, even if you feel a bit embarrassed.

The fluid or secretion freed from the prostate by the massage will flow down the urethra and out through the penis. This fluid is collected and tested for any bacteria (germs) which may be causing an infection.

Prostate massage may also be used to release fluid and relieve pressure within the prostate to help with pain during prostatitis.

Trans Rectal Ultrasound Scan (TRUS)

This is done when having a prostate biopsy. Sometimes to get a better picture and see the size of your prostate, you will be asked to have a Trans Rectal Ultrasound scan. This may be done by the urologist or CNS.

A small, ultrasound probe is coated with gel and gently passed into your back passage. It works by giving out sound waves. The echoes from the sound waves give a clear picture of the shape and size of your prostate which the doctor can see on a screen. You may find this a bit uncomfortable, but it shouldn’t hurt and it shouldn’t take too long. You may be asked to have a bowel movement so your back passage is empty before going for your appointment.

Ultrasound Scan

An ultrasound scan is used to look at your kidneys but can also measure how well your bladder is emptying. A doctor or radiographer (a radiographer deals with x-rays) runs a small probe over the surface of your tummy.

Urine Flow Measurement

If your prostate is blocking the opening from your bladder, this will make passing urine a lot slower. There is a machine to test this. The flow test works best if you pass a lot of urine more than 200mls ie a paper cup, so you might be asked to go into the hospital with a comfortably full bladder (but do not overfill your bladder) or you might be given water to drink and wait until your bladder is full. All you have to do is pass urine into a funnel-shaped container and all the measurements are recorded automatically!

Voiding diary

You may be asked to keep a ‘voiding’ diary. Voiding means passing urine.

Over a few days, you will be asked to write down things like:

•  The number of times you go to the toilet during the day to pass urine
• The number of times you get up during the night to pass urine
• The approximate time of the day you go to the toilet
• The amount of urine you pass
• How often do you feel that you’ve not been able to completely empty your bladder?
• How often do you ‘stop and start’ when going to the toilet
• How often do you find it difficult to hold your urine?
• How often have you noticed a weak stream of urine or urine not flowing as quickly as usual?
• If you have to push to make the urine start flowing
• What and how much you drank e.g. tea, coffee, water

The diary is a good way to find out more about your symptoms and can be used to decide on the best treatment for you. There is a chart included at the end of the booklet, which you could use to note down your answers.