Definition
What is a benign tumor?
A benign tumor is a noncancerous mass formed when cells multiply beyond the body's needs, or fail to die on schedule, but stay at one site. Its cells usually look and behave much like the normal tissue they came from, it tends to grow slowly, and it often has a smooth border or capsule, so it pushes neighboring structures aside rather than growing into them. It does not metastasize.
Benign does not always mean harmless. A benign tumor can grow large enough to press on nerves, blood vessels or organs, and inside the rigid skull even a slow-growing meningioma can be dangerous. Some, such as certain pituitary and thyroid tumors, release excess hormones. A few kinds, including the colon polyps called adenomas, can turn malignant over time, which is why they are removed when found.
Familiar examples are lipomas of fat tissue, uterine fibroids of smooth muscle and many thyroid nodules. Surgery is the usual treatment when one causes problems, and once removed completely a benign tumor rarely grows back.
Word parts
Where does the term “benign tumor” come from?
- benign
- kind, gentleLatin benignus, from bene (well) + genus (kind)
- tumor
- a swellingLatin tumor
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Terms that go with it
- TumorA tumor is an abnormal mass of tissue made by cells that multiply too much or fail to die on time; it can be benign or malignant.
- Malignant tumorA malignant tumor is a cancerous mass whose cells grow without control, invade surrounding tissue and can spread to distant organs.
- CancerCancer is a group of diseases in which abnormal cells divide without control, invade nearby tissue and can spread to distant parts of the body.
- MetastasisMetastasis is the spread of a cancer from its first site to distant organs, where escaped cells settle and grow into secondary tumors.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- NCI Dictionary of Cancer Terms: benign
- MedlinePlus: Benign Tumors
- National Cancer Institute: What Is Cancer?
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