The Harvard Gazette
September 8, 2022
Brigham and Women’s Hospital Communications
Altered microbiome, sleep deprivation, increase in alcohol consumption among possible culprits in 30-year global trend
A study by researchers from Brigham and Women’s Hospital reveals that the incidence of early onset cancers — including breast, colon, esophagus, kidney, liver, and pancreas — has dramatically increased around the world, with the rise beginning around 1990. In an effort to understand why many more people under 50 are being diagnosed with cancer, scientists conducted extensive analyses of available data, including information on early life exposures that might have contributed to the trend. Results are published in Nature Reviews Clinical Oncology.
“From our data, we observed something called the birth cohort effect. This effect shows that each successive group of people born at a later time — e.g., a decade later — have a higher risk of developing cancer later in life, likely due to risk factors they were exposed to at a young age,” said Shuji Ogino, a professor at Harvard Chan School and Harvard Medical School and a physician-scientist in the Department of Pathology at the Brigham.
“We found that this risk is increasing with each generation. For instance, people born in 1960 experienced higher cancer risk before they turn 50 than people born in 1950, and we predict that this risk level will continue to climb in successive generations.”
Ogino worked with lead author Tomotaka Ugai and colleagues from 2000 to 2012 to analyze global data on 14 cancer types that showed increased incidence in adults before age 50. Then the team searched for available studies that examined trends of possible risk factors, including early life exposures in the general populations. Finally, the researchers examined the literature describing clinical and biological tumor characteristics of early onset cancers compared with cancers diagnosed after age 50.
“We found that this risk is increasing with each generation.”