Radiation induced organizing pneumonia

Radiation induced organizing pneumonia (RIOP) is considered a form of inflammatory lung disease occasionally observed usually after irradiation to the breast. It is classified as a type of secondary organizing pneumonia that is characterized by infiltrative opacification "outside" the irradiated volume and are sometimes migratory. It should be differentiated from radiation-induced lung disease (RILD) such as radiation pneumonitis which are more localized forms of lung injury usually within the radiation field.