What is Radiosensitivity?

Radiosensitivity is a term used to describe the degree of response that a patient has to the use of radiation therapy to deal with a given ailment, such as cancer. While the degree of radiosensitivity is often focused on the rate of response to treatments using radiation, the term is also used to refer to how surrounding organs and tissue respond to those treatments. Gauging the degree of sensitivity to radiation allows physicians to determine the most productive level of radiation to use in order to treat the disease effectively while creating a minimum of disruption with the surrounding tissue.

Over the years, medical research has helped health professionals understand some of the factors that impact the best use of ionizing radiation in the treatment of cancerous growths. One has to do with the rate of cell division inherent in the surrounding tissue. Essentially, cells that are actively dividing or are not yet fully mature exhibit the highest degree of sensitivity to radiation treatments. Knowing this has been especially important when using radiation as part of cancer treatment, as it makes it easier to gauge the reaction of the surrounding tissue and organs.

Some organs and types of tissue exhibit a relatively low rate of radiosensitivity. These include the spinal cord, mature bones, the liver, and the thyroid. Others tend to exhibit a moderate amount of sensitivity to radiation, with the stomach and immature bones being two examples. The skin and any other organs that contain epithelial cell linings tend to be more sensitive to radiation; this includes organs like the rectum, bladder, and cornea.

Highly radiosensitive organs include the testes, ovaries, and the intestines. The lymphoid organs and the marrow of the bones also exhibit a high amount of radiosensitivity. Depending on the location of the cancer, medical professionals will attempt to determine the best dosage per treatment session that has the maximum impact on the tumor itself, while inflicting as little damage as possible on the organs in the immediate area. This process has improved over the years, as newer techniques have made it possible to administer the radiation with more precision, thus limiting the range of potential damage to a smaller area.

In many cases, the process of tumor radiation during cancer treatment causes very little damage to nearby organs and tissue. Often, the damage is temporary, and the individual will experience a full regeneration of healthy tissue as healthy cells continue to divide and mature. During the process of radiation treatments, healthcare professionals are ever mindful of the rate of radiosensitivity exhibited by the patient, making it possible to adjust both the dosage and the frequency of the treatments in order to achieve the best results.