Definition

A radioactive substance being studied as an imaging agent in head and neck cancer and other types of cancer. It binds to large molecules in cancer cells that have a low level of oxygen. Radiation given off by FMISO is detected by a positron emission tomography (PET) scan. Knowing the amount of FMISO in the cancer cells may help plan the best treatment and help predict whether the cancer will come back after treatment. Also called 18F-fluoromisonidazole, 18F-MISO, and fluorine F 18-fluoromisonidazole.