Treatment of Radiation Injury

Abstract

Significance: Radiation exposure as a result of radiation treatment, accident, or terrorism may cause serious problems such as deficiency due to necrosis or loss of function, fibrosis, or intractable ulcers in the tissues and organs. When the skin, bone, oral mucous membrane, guts, or salivary glands are damaged by ionizing radiation, the management and treatment are very lengthy and difficult. Critical Issues: In severe and irreversible injuries, surgery remains the mainstay of treatment. Several surgical procedures, such as debridement, skin grafting, and local and free-vascularized flaps, are widely used. Recent Advances: In specific cases of major morbidity or in high-risk patients, a newly developed therapy using a patient's own stem cells is safe and effective. Adipose tissue, normally a rich source of mesenchymal stem cells, which are similar to those from the bone marrow, can be harvested, since the procedure is easy, and abundant tissue can be obtained with minimal invasiveness. Future Directions: Based on the molecular basis of radiation injuries, several prospective treatments are under development. Single-nucleotide polymorphisms focus on an individual's sensitivity to radiation in radiogenomics, and the pathology of radiation fibrosis or the effect of radiation on wound healing is being studied and will lead to new insight into the treatment of radiation injuries. Protectors and mitigators are being actively investigated in terms of the timing of administration or dose.

Sadanori Akita, MD, PhD

Figure 1.

Radioprotectors and radiomitigators.

Figure 2.

Breast cancer, standardized mastectomy (Halsted), and 60-Gy irradiation. Ulcer and scar contracture continued for 35 years. Arrows indicate the scar contractures. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound

Figure 3.

(A) Meticulous debridement, including necrotic cartilage and bone. (B, C) After debridement, adipose-derived regenerative cells were injected in the edges and bottom of the wound and covered with artificial dermis. The arrows in (C) indicate the loosened tissue fibroses in the axilla and in the parasternal and the peri-wounded areas. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound

Figure 4.

Ex vivo cultured adipose-derived stem cells, days 3 (A), 8 (B), and 15 (C–E). (D) Induction medium; (E) Oil Red-O. Magnification, ×100. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound