The mechanisms of cancer in the aging population are driven by a combination of genetic, environmental, and biological factors that change as individuals age. Aging cells experience a decline in their ability to repair DNA damage, leading to an accumulation of mutations that contribute to cancer development. Additionally, age-related changes in the immune system, known as immunosenescence, reduce the body's ability to detect and eliminate cancer cells. The tumor microenvironment also alters with age, creating conditions that may promote cancer progression. Understanding how these aging-related changes influence cancer biology is crucial for developing therapies that are effective for older adults, who may experience different cancer types and progression patterns compared to younger patients.