radionecrosis
Pronunciation: ray-dee-oh-nuh-KROH-sis
Tissue death resulting from radiation therapy that can mimic tumor recurrence on imaging studies.
Full Definition
Radionecrosis is a delayed complication of radiation therapy characterized by tissue death, inflammation, and vascular changes that typically occurs months to years after treatment. In oncologic radiology, radionecrosis presents a significant diagnostic challenge because it can appear identical to tumor recurrence on conventional imaging, showing enhancement, mass effect, and surrounding edema. This phenomenon is most commonly encountered in brain imaging following stereotactic radiosurgery or whole-brain radiation. Advanced imaging techniques including perfusion studies, PET scans, and MR spectroscopy help differentiate radionecrosis from recurrent tumor, though definitive diagnosis may require tissue sampling or longitudinal follow-up.
Usage
Usage note: Single compound word; specify radiation treatment history when describing this finding.
In Context
- "The enhancing lesion was consistent with radionecrosis rather than tumor recurrence based on perfusion characteristics." — Brain MRI interpretation
- "Distinguishing radionecrosis from recurrent glioblastoma required advanced perfusion imaging." — Neuro-oncology report