S. Ogino and T. Ugai. Annals of Oncol;.35(12) 1071-1073. 2024
The incidence of early-onset cancer (EOC) diagnosed in individuals under the age of 50 has been increasing worldwide, which may be just the tip of the iceberg of larger emerging issues, including the rise of various chronic diseases across multiple generations. While this phenomenon was first recognized in colorectal cancer (CRC), EOCs in the bile duct, breast, bone marrow, esophagus, gallbladder, head and neck, kidney, liver, stomach, pancreas, and uterine corpus have also shown increasing trends that appear to exceed the incidence increases attributable to enhanced screening. There are increasing incidence trends of EOC in the thyroid, prostate, and skin (nonmelanoma) without a corresponding rise in mortality. A birth cohort effect exists in CRC, meaning that each successive birth cohort (i.e. later generation) experiences a higher risk of EOC at a given age. This suggests that exposure to risk factors in early life and young adulthood has increased over the decades since the mid-20th century. There has been a heated debate about the causes of the rise in EOC, which is likely a multifactorial phenomenon. As polygenic influences and insulin-related signaling seem to play etiological roles in EO-CRC, both nature and nurture are likely important. The degree or prevalence of many ofthese factors has changed since the mid-20th century, and the effects of early-life exposure on EOC incidence may take decades to become apparent. For instance, adulthood obesity may not be a true risk factor for EOC but rather a consequence of childhood or adolescence obesity, whichcould be the true risk factor. Researchers, public health professionals, policymakers, andthe general public must collaborate to combat the global EOC epidemic.
15 Apr, 2026