Diagnosis of prostate cancer

Check out this factsheet for a summary of the video.

Diagnosis is the process of finding out the cause of a health problem. Diagnosing prostate cancer usually begins with a visit to your family doctor. Your doctor will ask you about any symptoms you have and do a physical exam. Based on this information, your doctor may refer you to a specialist called a urologist or order tests to check for prostate cancer or other health problems. A urologist is a doctor who specializes in treating conditions of the genital and urinary tracts, including the prostate.

The process of diagnosis may seem long and frustrating. It's normal to worry, but try to remember that other health conditions can cause similar symptoms as prostate cancer. It's important for the healthcare team to rule out other reasons for a health problem before making a diagnosis of prostate cancer.

The following tests are usually used to rule out or diagnose prostate cancer. Many of the same tests used to diagnose cancer are used to find out the stage (how far the cancer has spread). Your doctor may also order other tests to check your general health and to help plan your treatment.

Health history and physical exam

Your health history is a record of your symptoms and risks and all the medical events and problems you have had in the past. Your doctor will ask questions about your history of:

  • symptoms that suggest prostate cancer
  • risks for prostate cancer

Your doctor may also ask about a family history of prostate cancer.

A physical exam allows your doctor to look for any signs of prostate cancer.

Find out more about physical exams.

Digital rectal exam (DRE)

A digital rectal exam (DRE) may be done as part of a physical exam. Your doctor inserts a gloved finger into the rectum to check the size and shape of the prostate and feel for any lumps or abnormal areas.

Find out more about a digital rectal exam (DRE).

Tumour marker tests

Tumour markers are substances found in the blood, tissues or fluids removed from the body. An abnormal amount of a tumour marker may mean that you have prostate cancer. The PSA test is one tumour marker test to help predict whether you have prostate cancer and if a biopsy should be done.

Prostate-specific antigen (PSA) test

The prostate-specific antigen (PSA) test is used to measure the level of PSA in the blood. PSA is a protein made by the prostate. When the PSA level is higher than normal, it may indicate prostate cancer.

PSA levels may also be high in those with non-cancerous conditions of the prostate, such as benign prostatic hyperplasia or prostatitis.

If you've been diagnosed with prostate cancer, your healthcare team will use the PSA test to measure your response to treatment or to check for signs that the cancer has come back (recurred) after treatment.

Find out more about the prostate-specific antigen (PSA) test.

Other tumour marker tests

Other tumour marker tests may be used along with the PSA test to help predict whether you might have prostate cancer and whether a biopsy should be done. But these are not standard tests and currently they may not be paid for through Canada's healthcare system. They are expensive and not widely used. They include the following.

4Kscore is a blood test that can predict the chances that you will develop high-risk prostate cancer.

Prostate Health Index (PHI) is a blood test that predicts the chances that you will develop prostate cancer.

Prostate Cancer Antigen 3 (PCA3) test is a urine (pee) test that looks for PCA3 in the urine. PCA3 is a gene that is normally present in low levels in the prostate. It is present in high levels in prostate cancer cells.

Complete blood count (CBC)

A complete blood count (CBC) measures the number and quality of white blood cells, red blood cells and platelets. It is done to check your general health and for signs of infection.

Find out more about a complete blood count (CBC).

Blood chemistry tests

Blood chemistry tests measure certain chemicals in the blood. They show how well certain organs are working and can help find abnormalities. Blood chemistry tests that can help stage prostate cancer include the following.

Blood urea nitrogen (BUN) and serum creatinine are measured to check how well the kidneys are working. If they are higher than normal, it may mean that the prostate is blocking the tubes that carry urine from the kidneys to the bladder (called the ureters).

Calcium and alkaline phosphatase levels in the blood may be measured. Higher than normal levels may mean that prostate cancer has spread to the bones and damaged them.

Find out more about blood chemistry tests.

Transrectal ultrasound (TRUS)

An ultrasound uses high-frequency sound waves to make images of parts of the body. A transrectal ultrasound (TRUS) uses an ultrasound probe placed in the rectum to make images of the prostate. It is used to:

  • guide a needle used to take tissue from the prostate during a biopsy

  • measure the size of the prostate
  • look for abnormal areas of the prostate

Find out more about a transrectal ultrasound (TRUS).

Biopsy

During a biopsy, the doctor removes tissues or cells from the body so they can be tested in a lab. A report from a pathologist will show whether cancer cells are found in the sample.

Prostate biopsy

A prostate biopsy may be done if the doctor finds an abnormal area during a DRE or TRUS. It may also be done if the PSA level is higher than normal or has gone up over time.

The type of biopsy used is called a core biopsy because the doctor uses a thin, hollow needle or probe to collect tissue samples (called cores). In most cases the doctor takes 10 to 12 samples from several areas of the prostate, including any abnormal areas. Collecting the samples can cause some discomfort, so the doctor may inject an anesthetic into the prostate before doing the biopsy. Find out more about core biopsies.

Doctors use imaging tests to help them guide the needle into the prostate gland. Most prostate biopsies are done using TRUS, but sometimes an MRI is used. They can collect samples from the prostate through the wall of the rectum, the perineum or the urethra.

If you have a prostate biopsy, you will be given antibiotics to prevent an infection (called prophylactic antibiotics) since there is a greater risk of infection with this type of biopsy. If you experience fever following a biopsy, see your doctor right away. Don't wait for your next planned appointment.

Transrectal biopsy uses TRUS to guide the needle through the wall of the rectum and into the prostate.

Transperineal biopsy uses TRUS to guide the needle through the skin of the perineum (the area between the scrotum and the anus).

The samples collected during a prostate biopsy are sent to the lab. The pathology report will say if cancer cells are in the sample. A positive biopsy means that cancer cells were found. A negative biopsy means that no cancer cells were found. If you have a negative biopsy, your doctor may do a repeat biopsy because in some cases a biopsy can miss cancer. If there is cancer, the pathologist will also give a Gleason score (grade) and Grade Group for prostate cancer. The Gleason score and Grade Group describe how aggressive the prostate tumour is and how likely it is to spread.

MRI fusion biopsy uses an MRI with TRUS. An MRI scan is used to identify any irregular areas in the prostate. Then an ultrasound of the prostate is done. Computer software combines the 2 images to produce a 3D image to target the exact area for the biopsy.

Transurethral biopsy uses a cystoscope (a tube-like instrument with a light and tiny video camera) passed through the urethra to reach the prostate. The doctor collects samples with tools passed through the cystoscope. A transurethral biopsy is not usually used to diagnose prostate cancer.

Other biopsies

The following biopsies may be used to find out if cancer has spread to lymph nodes or other areas of the body outside of the prostate.

Laparoscopic biopsy uses a laparoscope, which is a thin, tube-like instrument with a light and tiny video camera. The doctor makes a small incision (surgical cut) in the abdomen and inserts the laparoscope. The doctor uses a special tool on the laparoscope to remove samples or abnormal tissue from inside the abdomen or pelvis. A laparoscopic biopsy can also be used to remove lymph nodes in the pelvis so they can be checked for cancer.

Fine needle aspiration (FNA) uses a very thin needle and syringe to remove a small amount of fluid or cells. Doctors may use FNA to collect samples from lymph nodes around the prostate. Sometimes they use a CT scan to guide the biopsy needle. Find out more about a fine needle aspiration (FNA).

MRI

Magnetic resonance imaging (MRI) uses powerful magnetic forces and radiofrequency waves to make cross-sectional images of organs, tissues, bones and blood vessels. A computer turns the images into 3D pictures. Sometimes a dye (called a contrast medium) is injected into a vein before the MRI. The dye helps parts of the body show up better in the images.

Sometimes the images from MRI and TRUS are digitally combined to help identify those who are at risk of developing more aggressive disease.

An MRI is used to:

  • look for cancer in the front of the prostate that may be missed with other tests
  • look for prostate cancer when the doctor thinks it might be present but it isn't found with a biopsy
  • measure the size of the prostate or a tumour in the prostate
  • help plan radiation therapy to treat prostate cancer
  • guide the needle during a prostate biopsy

An MRI can also be used to see if cancer has spread outside of the prostate, such as to lymph nodes in the pelvis. This may be done for men who have higher than normal PSA levels, an abnormal area that was felt during a DRE, or a high Gleason score because these factors mean the cancer is more likely to have spread.

The following specialized types of MRI may be used to diagnose prostate cancer.

Multiparametric MRI (mpMRI) uses several different types of MRI tests (called MRI sequences) that show different details on the MRI image. While a standard MRI can find a tumour in the prostate, a mpMRI gives more details about the exact location of the tumour, how aggressive it is and whether or not it has spread outside of the prostate. A mpMRI can help doctors better target an abnormal area during a prostate biopsy. It can also help doctors decide who should be treated right away and who may benefit most from active surveillance.

Your doctor may give you a Prostate Imaging Reporting and Data System (PI-RADS) score based on your mpMRI. This can help your doctor decide whether you need to have a biopsy. A PI-RADS score is a number from 1 to 5. The bigger the number, the more likely you have prostate cancer and need a biopsy. A PI-RADS score of 1 means that it's very unlikely that you have prostate cancer. A PI-RADS score of 5 means that it's very likely that you have prostate cancer.

MRI using an endorectal coil uses a thin wire surrounded by a small, inflated balloon that is placed inside the rectum. This type of MRI is sometimes used to get a better image of the prostate than a standard MRI. You may be given a mild sedative or a muscle relaxant to help make you more comfortable.

Find out more about MRIs.

Bone scan

A bone scan uses bone-seeking radioactive materials (called radiopharmaceuticals) and a computer to create a picture of the bones. It is used to look for prostate cancer that has spread to the bones. Doctors don't usually do a bone scan if you have a low PSA level, a normal DRE and a low Gleason score because these factors mean that the cancer is very unlikely to have spread outside the prostate.

A bone scan is also used to monitor response to treatment in those with metastatic prostate cancer (cancer that has spread).

Find out more about bone scans.

CT scan

A computed tomography (CT) scan uses special x-ray equipment to make 3D and cross-sectional images of organs, tissues, bones and blood vessels inside the body. A computer turns the images into detailed pictures. Sometimes a dye (called a contrast medium) is given by mouth or injected into a vein before the CT scan. The dye can help the doctor see structures of the body better.

A CT scan can be used to look for cancer that has spread outside of the prostate, such as to the chest, abdomen or pelvis. Doctors don't usually do a CT scan to look for cancer spread if you have a low PSA level, a normal DRE and a low Gleason score because these factors mean that the cancer is less likely to have spread outside of the prostate. A CT scan can also be used to guide a needle during a biopsy of lymph nodes near the prostate.

A CT scan is sometimes combined with a PET scan (called a PET-CT scan) to learn more about the cancer. This is not a standard test.

Find out more about CT scans.

Questions to ask your healthcare team

To make the decisions that are right for you, ask your healthcare team questions about a diagnosis.

Expert review and references