Incidence of 17 types of cancer is rising among Generation X and millennials, finds a study from the American Cancer Society published in the journal The Lancet Public Health.
Researchers used data from 23.6 million patients diagnosed with 34 types of cancer and from 7.3 million cancer deaths, for adults aged 25–84 years between 2000 and 2019. To compare cancer rates across generations they broke the data down into five-year birth intervals from 1920 to 1990 and analysed cancer incidence and death among birth cohorts.
Incidence of cancer increased with each successive birth cohort since 1920 for 17 of 34 types of cancer. People born in 1990 have two to three times higher rates of pancreatic, kidney and small intestinal cancers in both men and women, and for liver cancer in women, than people born in 1955. Other cancers that have increased in younger generations after a decline in older birth cohorts include liver, breast, uterine, colorectal, gastric, gallbladder, ovarian, testicular cancer and anal and Kaposi sarcoma cancers in men.
Correspondingly, cancer deaths also increased for younger generations for colorectal, liver (female only), uterine, gallbladder and testicular cancers.
Researchers couldn’t find a clear explanation for why the rates are rising. “The data highlights the critical need to identify and address underlying risk factors in Gen X and millennial populations to inform prevention strategies,” the study said.
