radiosensitivity
Degree to which cells or tissues are susceptible to damage from ionizing radiation exposure.
Full Definition
Radiosensitivity refers to the relative susceptibility of cells, tissues, or tumors to radiation-induced damage. Highly radiosensitive tumors (such as lymphomas, seminomas, and certain sarcomas) typically respond well to relatively low radiation doses, while radioresistant tumors (like melanoma, renal cell carcinoma, and some sarcomas) require higher doses for equivalent effect. Factors affecting radiosensitivity include cell cycle phase, oxygenation status, DNA repair capacity, and intrinsic cellular characteristics. Understanding tumor radiosensitivity guides treatment planning, dose prescription, and the integration of radiation with other therapeutic modalities.
Usage
Usage note: Distinguished from radioresponsiveness, which refers to clinical tumor shrinkage after radiation.
In Context
- "The high radiosensitivity of seminoma allows for lower prescription doses." — Treatment planning notes
- "Tumor radiosensitivity will influence the choice of fractionation schedule." — Radiation oncology consultation