Researchers found a three-fold increased risk of having a high-grade tumour in these men, no matter whether the heavy drinking occurred in youth – ages 15 to 19 – or in later decades, according to the results published in Cancer Prevention Research. There was no link, however, between current alcohol consumption and tumour grade.
The original intent of the study was to look at the youngest age group, thinking that alcohol might have a deleterious effect on the developing prostate, said the study’s senior author, Emma Allott, who oversaw the research while a faculty member at the University of North Carolina, Chapel Hill.
“We initially set out to look at the teenage years but we also saw an elevated risk in many of the decades up to midlife,” said Allott. “This highlights the need to look throughout the lifespan if you want to understand whether alcohol has any role in the development or the aggressiveness of prostate cancer.”
Allott isn’t ready to tell men to quit drinking. There needs to be more research backing up her study before any kind of recommendation is made, she said.
Still, there are other reasons to scale back, she said, “Mainly in light of recommendations regarding alcohol and other cancers.”
Allott and her colleagues analysed data gathered from 650 men who were undergoing a prostate biopsy at the Durham Veterans Affairs Medical Center in North Carolina between January 2007 and January 2018. The veterans in the study, whose ages ranged from 49 to 89, had no prior history of prostate cancer.
The study population was unusually diverse: 54 per cent of the participants were non-white. That’s important, experts said, because this cancer hits African Americans harder than whites.
Coupled with the information from the biopsies of the men’s tumours was data on alcohol consumption and other medical and lifestyle factors that came from questionnaires the men filled out.
The researchers also looked at lifetime alcohol exposure and found a more than three-fold increased risk of a high-grade tumour in men who consumed more than 10,660 drinks – which works out to about one drink a day for 30 years.
One potentially confounding factor is that many of the men with high grade tumours also smoked. There has been some research showing that smoking is associated with high tumour grade, Allott said. “Because alcohol and smoking are two behaviours that go hand in hand, it’s difficult to tease out the potential effects of alcohol from smoking,” she added.
“If I am a sober person who drank heavily in my youth, I wouldn’t worry too much,” said Dr Christopher Saigal of the University of California, Los Angeles Jonsson Comprehensive Cancer Center, who wasn’t involved in the research.
“The study has limitations. For one thing, it’s an association (rather than proof of cause). Also, they didn’t find that alcohol raised the risk of prostate cancer, but instead, that a subset of men might be at risk for high-grade disease,” he added.
The study wasn’t large enough for the researchers to be able to tell whether men’s drinking styles – whether consuming a drink or two each day or bingeing on the weekends – had an impact, noted Dr Anne McTiernan of the Fred Hutchinson Cancer Research Center in Seattle, Washington.
“But it gives a hint at the high relative risks of alcohol exposure,” said McTiernan, who wasn’t involved in the study.
“The bottom line, I would say, is that you should minimise alcohol intake just as we do with many other cancers. Most organisations say that for men you should have no more than two drinks a day. If you’re concerned about cancer risk, maybe that should be even lower.”
There are plenty of other reasons young men shouldn’t be drinking on a daily basis, said Dr Leonard Appleman of the University of Pittsburgh Medical Center in Pennsylvania. “But this is another example of chronic alcohol consumption’s long-term impact in many areas.” The fact that current drinking wasn’t associated with high grade tumours “fits in with what we know about prostate cancer. It’s decades in the making. The mutations start in early adulthood and build up over the decades.”