Radiotherapeutic normal tissue injury can be viewed as two simultaneously ongoing and
interacting processes. The first has many features in common with the healing of traumatic
wounds. The second is a set of transient or permanent alterations of cellular and
extracellular components within the irradiated volume. In contrast to physical trauma,
fractionated radiation therapy produces a series of repeated insults to tissues that undergo
significant changes during the course of radiotherapy. Normal tissue responses are also …