A prostate biopsy is the most accurate way of determining whether a person has prostate cancer. However, doctors may recommend other, less invasive tests beforehand.
If doctors suspect a person has prostate cancer, they
The American Cancer Society (ACS) explains that high levels of PSA may indicate prostate cancer, but doctors will need to do further tests.
This article explains the different tests doctors use to diagnose prostate cancer and their accuracy. It also explores new developments in testing.
Doctors
For a prostate biopsy, doctors remove small samples of prostate tissue and examine them under a microscope. They usually collect several samples from different parts of the prostate.
The prostate sits just in front of the rectum, below the person’s bladder.
For this procedure, doctors collect the tissue sample with a hollow needle, which they insert through the rectum wall or the skin connecting the scrotum and anus.
The
Doctors usually take around 12 samples from different areas of the gland.
While biopsies are the most accurate way of diagnosing prostate cancer, they are not guaranteed. A person may need additional testing.
The PSA test is a blood test for prostate-specific antigens. If a person has high levels of this antigen in their blood, they
Doctors usually start with this test, as it is a marker for cancer, but is not a definitive diagnosis, as there are many other reasons the levels may be high.
The National Cancer Institute (NCI) cautions that these tests can give false-positive results. It estimates that as many as
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Doctors sometimes perform a physical exam where they insert a gloved and lubricated finger inside the person’s rectum to feel for any irregularities in the prostate.
This is called a digital rectal examination, but a US Preventive Services Task Force statement from 2018 does not recommend its use, saying it has no diagnostic benefits.
Doctors sometimes recommend an MRI to help them find the best places to insert their biopsy needles, or during the biopsy to help them position the needles.
Another type of MRI, called a multiparametric MRI, produces a more detailed picture of the person’s prostate.
A 2016 paper estimates that these scans are around
Doctors screen people for cancers in the hope of finding them before they have had a chance to spread.
However, the
Most people with prostate cancer have an extremely slow-growing form and may never experience issues during their lifetime.
The CDC advises people to discuss the advantages and disadvantages of screening with a doctor, as well as finding out about potential tests and treatment before deciding.
The US Preventive Services Task Force recommends against PSA screening for people aged 70 years and over.
The
Doctors are exploring new ways of conducting tests, including combining MRI scans with transrectal ultrasounds to locate the most likely places in a person’s prostate for biopsy. This procedure is called an MRI-targeted biopsy.
Other research includes using artificial intelligence to interpret MRIs and genetic testing to identify people at high risk.
This section answers common questions about the most accurate tests for prostate cancer.
Can a blood test detect prostate cancer in the body?
The PSA blood test checks prostate-specific antigen levels in a person’s blood. High levels of this antigen may indicate that the person has cancer, but it can also be due to other reasons.
Doctors can also test blood using the prostate health index, which is more accurate, but doctors rely on a biopsy to diagnose prostate cancer.
Is an MRI of the prostate better than a biopsy?
An MRI scan can help plan and execute biopsies, but a doctor cannot use it solely to diagnose prostate cancer.
An MRI provides a picture of a person’s prostate, which may indicate areas where cancerous cells are growing. This is useful, as it shows where doctors are most likely to collect a cancerous sample during a biopsy.
However, doctors do not use MRI results alone to diagnose prostate cancer.
A biopsy is the most accurate test for prostate cancer, particularly when doctors use imaging scans, such as MRIs or transrectal ultrasounds, to guide them to the most likely sample sites.
Blood tests, including the PSA and PHI tests, give doctors an insight into the person’s prostate-specific antigen levels, which they may use as markers for the possibility of cancer.
However, many people with high PSA levels do not have cancer.