People who smoke or drink heavily may develop pancreatic cancer at an earlier age than folks who avoid those habits, a new study suggests.
It's long been known that smoking is a risk factor for developing pancreatic cancer - a disease that is rarely caught early and has a grim prognosis. The evidence on heavy drinking has been more mixed, but some studies have suggested it's also a risk factor.
Now, the new results show the disease may strike smokers and drinkers earlier in life.
What the study found
"If you do have these habits, and you're going to develop pancreatic cancer, the age of presentation may be younger," said lead researcher Dr Michelle A Anderson, of the University of Michigan Health System in Ann Arbor.
Her team also found that the effect disappeared for former smokers or drinkers if they had quit 10 years or more before being diagnosed.
On average, the risk of developing pancreatic cancer in your lifetime is about one in 71. And the average age at diagnosis is 72, according to the American Cancer Society.
But in this study, current smokers and heavy drinkers were diagnosed a decade earlier than that.
That could be an important motivator for people to quit smoking or curb their drinking, according to Dr Anderson. "That's potentially an extra decade of life," she said.
A dose effect
The findings, reported online in the American Journal of Gastroenterology, are based on 811 patients in a pancreatic cancer registry.
Those who were current smokers were typically diagnosed around age 62, versus age 70 among non-smokers. Heavy drinkers, meanwhile, were typically diagnosed at age 61 - almost a decade earlier than non-drinkers.
Heavy drinking was defined as roughly three or more standard drinks a day. A 12-ounce beer or five ounces of wine would equate to a standard drink.
Dr Anderson's team accounted for a number of covariates, like body weight and family history of pancreatic cancer. And smoking and heavy drinking were still linked to earlier diagnoses.
What's more, Dr Anderson noted, there was a "dose" effect.
Smokers who went through more than a pack a day were diagnosed at a younger age than people who smoked less than a pack per day. And once people had refrained from smoking or heavy drinking for a decade, the excess risk of an early cancer seemed to disappear.
According to Dr Anderson, the findings could have implications in the future, if widespread screening for pancreatic cancer becomes a reality.
Right now, there's no test that reliably detects pancreatic cancer in people who have no symptoms. So, even people with a strong family history of the disease are not routinely screened.
In order to move toward screening, doctors not only need good tests, but also to know who to screen and at what age to start, Dr Anderson explained.
If smokers and heavy drinkers do tend to develop pancreatic cancer earlier, that could help experts figure out which people could benefit from screening, and when it should begin.
(Reuters Health, September 2012)