NEHA Radiation Protection Practice Exam

Fractionation, in the context of radiation therapy, refers to the method of delivering radiation in smaller, more manageable doses over a longer period rather than a single large dose. This approach is particularly beneficial because it provides healthy tissues with the necessary time to recover between treatments.

When radiation is administered in fractions, normal cells, which typically have a better ability to repair DNA damage compared to cancer cells, are given the opportunity to heal from the effects of radiation. The cancer cells, on the other hand, may not repair as effectively due to their nature, which often includes a compromised or dysfunctional repair mechanism.

This selective benefit favors healthy tissue preservation while still effectively targeting malignant cells, ultimately enhancing the therapeutic ratio—the balance between killing cancer cells and sparing healthy ones. By using this strategy, clinicians can maximize tumor control while minimizing unwanted side effects in surrounding healthy tissues.