Smokers face an increased risk of certain types of throat and stomach cancers, even years after they quit, a new study finds.
Combining the results of 33 past studies, Italian researchers found that current smokers were more than twice as likely as nonsmokers to develop cancer, either in their esophagus or in a part of the stomach called the gastric cardia.
In some of the studies, the risk of esophagus cancer remained high even when people had quit smoking three decades earlier.
The two cancers, both known as adenocarcinomas, are relatively uncommon in Western countries. Rates elsewhere are much higher, especially in less developed countries. But in recent decades, rates of the cancers have been rising in the U.S. and Europe -- possibly related to growing rates of obesity.
Smoking has long been considered a risk factor for the two cancers.
But these latest findings offer a "better quantification" of the risks, said senior researcher Dr. Eva Negri, of the "Mario Negri" Institute of Pharmacological Research in Milan.