Lesion is a general imaging term for an abnormal area seen in tissue or an organ.
A lesion itself is an imaging description, so symptoms depend on where it is and what is causing it. Some lesions cause no symptoms, while others relate to pain, swelling, bleeding, or organ-specific problems.
Imaging helps describe the lesion's size, shape, location, and behavior, which guides whether it looks harmless, needs follow-up, or needs more testing.
Radiologists use the word when describing something unusual before its exact nature is fully known.
Some lesions are harmless and only need observation, while others need more imaging, biopsy, or treatment depending on their features.
This entry explains the word. If it appeared on your report, the next step is getting that report interpreted for your case.