Global Burden of Disease Study indicated that, neoplasms ranked as the third leading Level 2 cause of disability-adjusted life years (DALYs) and mortality in 2021 [1]. According to the most recent estimates from the International Agency for Research on Cancer (IARC), Türkiye recorded 240,013 new cancer cases and 129,672 cancer-related deaths in 2022 [2]. The distribution of the five most prevalent cancer types in Türkiye aligns with global and developed country patterns. According to GLOBOCAN 2022 data, the most commonly diagnosed cancers in men in Turkey are lung, prostate, colorectal, bladder, and stomach cancers, while in women, the most frequent types are breast, thyroid, colorectal, lung, and corpus uteri cancers [2]. National cancer statistics from 2008 to 2017 reveal that cancer incidence trends have remained consistent across both genders over the years. Based on projections of cancer incidence in Türkiye from 2017 to 2023, a continued increase in cases is anticipated [3].

The Age-Period-Cohort (APC) analysis is a methodological approach used to identify patterns in cancer incidence or mortality by decomposing the effects of age, time, period, and birth cohort. Age effects encompass biological changes and life experiences unique to individuals, influencing their susceptibility to cancer over time [4]. These age effects are independent of the time period or birth cohort and manifest as variations in disease rates across different age groups [5]. Period effects stem from external factors that uniformly affect all age groups within a specific time frame. These influences may result from significant events such as wars, famines, economic crises, or changes in methodologies related to data collection, disease classification, or outcome definitions [6]. Cohort effects represent variations associated with the unique experiences or exposures of specific groups, typically defined by birth year. These effects underscore differences in health risks across birth cohorts, primarily driven by age-specific exposures or susceptibilities to environmental, behavioral, or socioeconomic factors [7].

In Turkey, the population is aging, and demographic structure, sociocultural factors, lifestyle patterns, and economic conditions are undergoing significant changes. Alongside these transformations, an increase in cancer burden is anticipated. Therefore, this study aims to estimate the independent impacts of age, period and cohort effect on cancer incidence in Türkiye from 1990 to 2019 based on data from the Global Burden of Disease (GBD) Study 2021.