Researchers at Stanford University have uncovered new insights into why cancer risk declines significantly in people above the age of 85. While cancer likelihood typically rises through middle age and early old age, scientists have long observed that the trend unexpectedly slows or even reverses in very advanced age. The latest study offers a clearer understanding of this pattern.
The research team, led by Emily G. Shuldiner, Dmitri A. Petrov and Monte M. Winslow, explored this phenomenon using genetically engineered mice. The mice were separated into two age groups—4 to 6 months and 21 to 22 months—and were introduced to the KRAS mutation, one of the most common genetic triggers for cancer. Results showed that the older mice had two to three times fewer tumors than the younger group.
According to the researchers, aging tissues develop biological mechanisms that naturally suppress tumor formation. Although older bodies accumulate more mutations over time, they also gain stronger internal processes that prevent these mutations from progressing into full cancer. Further analysis revealed that tumor suppressor genes were harder for cancer cells to inactivate in older mice, making it more difficult for tumors to grow.
Experts believe this discovery could shape future cancer treatments by helping scientists better understand how aging alters the body’s response to harmful mutations. It may also guide new approaches for prevention across different age groups.
Health organizations like the World Health Organization emphasize that nearly half of cancer cases worldwide are preventable through lifestyle choices such as avoiding tobacco, limiting alcohol, maintaining a healthy weight, preventing infections and reducing exposure to pollutants and radiation. However, widespread environmental factors—like air pollution—continue to present major challenges.
This study strengthens ongoing efforts to understand cancer risk across ages and may open new pathways for prevention and treatment strategies in the future.