Margin
Also known as: surgical margin, resection margin
The rim of normal-looking tissue around a tumour after it is surgically removed.
Definition
When a tumour is removed surgically, the pathologist inks the outer surface of the specimen and examines it under the microscope to see whether any cancer cells reach that surface. The strip of tissue around the tumour is called the margin.
A clear (negative) margin means no cancer cells are seen at the edge, suggesting the tumour was removed completely. A positive margin means cancer cells extend to the cut surface and additional treatment — further surgery, radiation, or systemic therapy — may be needed to reduce the risk of recurrence.
See also
- Resection — Surgery to cut out a tumour, often together with a rim of surrounding normal tissue.
- Excisional Biopsy — A biopsy in which the entire lump or suspicious area is removed for examination.
- Mastectomy — Surgery to remove all or most of the breast tissue, usually to treat breast cancer.
- Recurrence — The return of cancer after a period of being undetectable.
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Medically reviewed by
Dr. Rehan Abdullah
Dr. Rehan Abdullah is a dual-trained clinical and radiation oncologist with over a decade of experience treating both solid tumours and hematologic malignancies. He serves as Consultant Oncologist at INMOL Hospital and sees patients at Farooq Hospital and Healthnox Medical Center, Lahore. Read full profile →
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