What does the Tissue Weighting Factor represent?

The Tissue Weighting Factor is a crucial concept in radiation protection and dosimetry that reflects the relative sensitivity of different tissues and organs to the harmful effects of ionizing radiation, particularly in the context of stochastic risk. This factor assigns a value to each organ, representing the proportion of the total risk of cancer and hereditary effects attributable to exposure of that specific organ or tissue to radiation.

In this context, the Tissue Weighting Factor helps quantify the risk of cancer induction as a function of the organ's radiation exposure. Since some organs, such as the lungs or breast, are more sensitive to radiation than others, their Tissue Weighting Factors are higher, indicating a greater risk contribution to the overall stochastic risk when they are irradiated.

Understanding this factor is essential for medical dosimetrists, as it helps guide treatment planning to minimize potential risks to sensitive tissues while delivering effective radiation therapy to tumors.