Abstract
The analysis of cancer incidence trends in adolescents and young adults reveals a concerning increase. This observational study aims to investigate cancer incidence trends among young adults under 50, compared to older age trends, using the population-based Cancer Registry of the Veneto Region (Northeastern Italy) from 1987 to 2019. Yearly age-standardized cancer incidence rates per 100,000 individuals were obtained from the Veneto Tumour Registry for 24 tumor sites and all cancers combined. Temporal trends from 1987 to 2019 were analyzed for each cancer type, stratified by sex and age group at diagnosis (0-49, 50-64, and 65+ years). Significant changes in incidence trends were assessed by the annual percent change (APC), calculated through joinpoint regression analysis. Since 1987, the incidence rate of cancers among young adults decreased in males, while among females it increased until 2014 and then stabilized. One cancer showed increasing incidence in both sexes (invasive cutaneous melanoma), two in males (testicular, and multiple myeloma), and two more in females (breast, and Hodgkin disease). Four cancer sites showed a decline in both sexes (oral cavity, stomach, lung, and bladder), and four further cancers only in males (esophagus, rectum, larynx, and non-Hodgkin lymphoma). Two cancers showed complex trends (Corpus uteri, and thyroid in women). Eight cancers showed no significant changes in APCs. Cancer incidence data for young adults reveal a heterogeneous landscape. These findings provide valuable insights into the expected evolution of cancer epidemiology in young populations.