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How does fractionation reduce complications from radiation therapy?

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linear accelerator; external beam radiation therapy — radiation therapy External beam radiation therapy (also known as external beam teletherapy, or long-distance therapy) being delivered using a machine known as a linear accelerator.

In radiation therapy, fractionation refers to the administration of the total radiation dose in repeated, smaller doses rather than a single large exposure.1

This process reduces complications and enhances treatment efficacy by leveraging the biological differences between cancer cells and healthy tissue. Because cancer cells are continuously proliferating, they are generally more sensitive to radiation damage and less capable of recovery than normal, healthy cells.1

When radiation is delivered in widely spaced fractions, healthy cells are provided with the necessary time to undergo DNA repair of sublethal damage between successive exposures. By breaking the treatment into smaller parts, clinicians can maximize the therapeutic effect on the tumor while allowing surrounding healthy tissues to recover, thereby minimizing the risk of serious side effects and complications.21