In Situ
Also known as: stage 0, non-invasive
Early-stage cancer that has not yet broken through into surrounding tissue.
Definition
"In situ" is a Latin phrase meaning "in its original place". A carcinoma in situ is an early cancer in which the abnormal cells are still confined to the layer in which they began and have not broken through the basement membrane into nearby tissue. It is sometimes called "stage 0" cancer.
Because in-situ disease has not yet acquired the ability to invade tissue or spread to lymph nodes, it is highly curable, usually with local treatment such as surgery (often with clear margins) and sometimes radiation. Common examples include ductal carcinoma in situ (DCIS) of the breast and high-grade cervical intra-epithelial neoplasia.
See also
- Invasive — Cancer that has grown beyond its starting layer into surrounding tissue.
- Carcinoma — Cancer that begins in the surface (epithelial) cells lining the skin and internal organs.
- Staging — The process of finding out how large a cancer is and whether it has spread.
- Margin — The rim of normal-looking tissue around a tumour after it is surgically removed.
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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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