Which individual is most likely to develop radiation-induced carcinogenesis from equal doses of radiation?

• A. Adolescent Female
• B. Elderly Male
• C. Elderly Female
• D. Adolescent Male

Answer: (B)

Radiation-induced carcinogenesis is a stochastic effect, so the risk after a given dose depends strongly on age at exposure. Younger individuals have more years ahead for a cancer to develop and their tissues are more mitotically active, making DNA damage more likely to persist and lead to malignancy over time. An adolescent, with rapid tissue growth and a longer remaining lifespan, faces a higher lifetime risk of cancer from the same dose than an elderly person. The elderly have less time for a latent cancer to appear, so the relative likelihood is lower despite any other age-related changes in repair. In short, the adolescent is most likely to develop radiation-related cancer after equal exposure because of greater cellular activity and a longer window for cancer to manifest.