The Dose20:31How can I protect myself from prostate cancer?
Prostate cancer is the most common cancer in men, with an estimated one in eight Canadian men expected to be diagnosed in their lifetimes.
Experts like University of Alberta oncology professor John Lewis say the vast majority of men will have “some cancer in their prostate at some point in their lives.”
“For prostate cancer that remains in the prostate, localized, the survival rate at five years is virtually 100 per cent,” Lewis told The Dose host Dr. Brian Goldman.
Still, the Canadian Cancer Society estimates that, on average, 14 Canadian men are expected to die from prostate cancer every day in 2024.
“Some prostate cancers are extremely aggressive,” said Lewis.
As a researcher who promotes Movember — an annual campaign in which men grow moustaches to raise awareness about men’s health every November — Lewis says the key for physicians and patients is understanding the risks associated with prostate cancer, in order to determine how to screen for and treat the disease.
What is prostate cancer?
The prostate is a gland that’s part of the male reproductive system, found just under the bladder and next to the rectum.
Lewis says he views prostate cancer as two distinct diseases “with two completely different outcomes”: what’s known as indolent cancer, which grows slowly and is less dangerous; and metastatic cancer, which spreads outside the prostate and is extremely dangerous if not caught early.
“Indolent prostate cancer … is a cancer that we often say men could die with and not of,” he said.
In contrast, approximately three per cent of men will die of aggressive prostate cancer.
In its early stages, people with prostate cancer may not experience many — or any — symptoms.
Once the tumour grows however, symptoms include more frequent urination, blood in the urine or semen, difficulty urinating, painful ejaculation, as well as back, hip and pelvis pain.
Who gets prostate cancer?
Anyone with a prostate – including men, trans women and non-binary people – is at risk of developing prostate cancer. The risk of prostate cancer increases with age, but a family history of prostate cancer is also a risk factor.
Poor diet, a lack of exercise and excessive alcohol consumption can also increase your chances of developing prostate cancer.
Surgeon Dr. Adam Kinnaird says U.S. data indicates Black men tend to have higher rates of prostate cancer, as well as more aggressive prostate cancer than men of other racial or ethnic backgrounds. In Canada, however, Kinnaird says Black men were not found to have worse rates of prostate cancer or more aggressive disease.
“But on average, Black men were diagnosed about two years earlier than other Canadians,” said Kinnaird, assistant professor at the University of Alberta’s faculty of medicine and dentistry.
Research indicates, however, that Indigenous men in Canada were more likely to have more advanced and more aggressive prostate cancer than other men, perhaps because Indigenous men were less likely to get screened with a prostate-specific antigen (PSA) test and were diagnosed at later stages of the disease.
The Canadian Cancer Society suggests that most men be screened for prostate cancer at the age of 50. Black and Indigenous men, as well as men with a family history of prostate cancer, should be screened around age 45.
Screening for prostate cancer
Doctors screen for prostate cancer using a PSA test or a digital rectal exam (DRE); the age screening starts depends on risk factors, and where you live.
If the PSA test detects higher than normal levels of the antigen in a patient’s blood — typically higher than three nanograms per litre — that might be an indication of prostate cancer.
Lewis says the PSA test is quite sensitive, though it doesn’t specify whether someone has indolent or metastatic cancer.
A new prostate cancer screening test is being offered in Alberta. The blood test is used in addition to a prostate-specific antigen test. Dr. John Lewis explains the test a dozen years in the making.
If high levels of PSA are detected in a person’s blood, Lewis says the only definitive way to confirm the presence of prostate cancer is through a biopsy.
“A biopsy includes a transrectal ultrasound, and then they stick about 12 needles up between the legs into the prostate,” he said. Biopsies carry the risk of infection that can lead to sepsis, which is why Lewis works on research aimed at improving less invasive prostate cancer screening.
How do we treat prostate cancer?
Though there is no cure for metastatic prostate cancer, Kinnaird says radiation and surgery are currently the two primary treatments for the disease if the cancer is localized to the prostate.
“The two first-line treatments options are having the whole prostate removed or radiation to the whole prostate,” he said.
Researchers from the University of Alberta have released a new study saying that Indigenous men are at higher risk of developing aggressive prostate cancer. We spoke with Doctor Adam Kinnaird, one of the co-authors of the study.
Brachytherapy – a treatment that inserts radioactive small material into the prostate to kill the cancerous cells – is also sometimes used.
That being said, a 2024 study found that 6.4 per cent of men treated with brachytherapy men had new cancer at 15 years of follow-up, increasing to 9.8 per cent after 20 years.