What is a benign tumor?
A tumor is an abnormal collection of cells. It forms when cells multiply more than they should or when cells don’t die when they should. A tumor can be malignant (cancerous) or benign (not cancerous).
A benign tumor is usually not a serious problem unless it presses on a nearby structure or causes other symptoms. Another word for tumor is neoplasm.
What’s the difference between a benign vs malignant tumor?
A benign tumor has distinct, smooth, regular borders. A malignant tumor has irregular borders and grows faster than a benign tumor.
A malignant tumor can also spread to other parts of your body. A benign tumor can become quite large, but it will not invade nearby tissue or spread to other parts of your body.
Can a benign tumor become malignant?
Some benign tumors can become cancerous over time (for example, in your colon or skin). If you have a benign neoplasm, a healthcare provider should monitor it regularly.
What are the different types of noncancerous tumors?
A benign tumor can grow anywhere on or in your body. These neoplasms have different names depending on where they develop:
- Adenoma: This is a benign tumor on or in a gland or organ (such as the pituitary gland, colon or liver).
- Chondroma: A chondroma is a benign neoplasm that forms in cartilage, a flexible connective tissue throughout the body.
- Fibroma or fibroid: This is a noncancerous tumor in the fibrous tissue, a dense connective tissue in tendons and ligaments. Fibromas can grow in fibrous tissue throughout your body. They are most common in your skin, mouth, foot and uterus (called uterine fibroids).
- Hemangioma: These types of benign neoplasms grow from blood vessels. Hemangiomas most often occur on the skin in babies. But they can also form on internal organs such as the liver, colon or brain.
- Lipoma: A lipoma forms from fat cells. This benign fatty tumor grows just below your skin. It’s the most common type of benign tumor.
- Lymphangioma: This type of benign neoplasm develops in your lymphatic system. It can cause fluid-filled cysts on your skin and mucous membranes, which line your mouth, nose and inner eyelids.
- Meningioma: Meningiomas begin in the meninges, a layer of tissue around your brain. They can press on the brain and spinal cord. Most meningiomas are benign, but they can grow large and become life-threatening.
- Myoma: These benign tumors grow from smooth muscle. Leiomyomas often grow in the uterus (also known as uterine fibroids) or gastrointestinal tract.
- Neuroma: This type of benign neoplasm develops within nerves. They can grow anywhere in your body. Common neuromas include schwannoma, neurofibroma and ganglioneuroma.
- Osteoma: This noncancerous tumor forms from bone. New, abnormal bone grows on other bone. Most osteomas grow on your skull. Osteoid osteomas develop in long bones, such as those in your legs. They are most common in children and young adults.
- Skin tumors: There are many types of benign skin tumors. Some of the most common include cherry angioma, sebaceous hyperplasia, seborrheic keratoses, dermatofibromas and acrochordons (also called skin tags).
Symptoms and Causes
What causes a benign neoplasm?
Scientists don’t yet understand what causes most noncancerous tumors. Some types may be related to genetics or exposure to chemicals or radiation.
What are the symptoms of a benign tumor?
Many benign neoplasms don’t cause any symptoms at all. But if they grow large enough to press on bodily structures, they may cause:
- Bleeding (for example, with a fibroid in the uterus).
- Headaches, seizures or trouble seeing (for example, with a brain tumor).
- Loss of appetite or weight loss (for example, a tumor near your stomach or intestines).
- Pain or discomfort in any area of your body.
- Trouble breathing (when the tumor is near your mouth, nose, throat or lungs).
On the skin, you can often see and feel benign tumors. They may be:
- Discolored (often red or brown).
- Firm or soft when you press on them.
- Raised, like bumps.
- Round, with smooth, even edges.
- Smooth or rough to the touch.
Diagnosis and Tests
How is a benign tumor diagnosed?
If you have any symptoms or see or feel anything that looks abnormal, you should talk to a healthcare provider. Certain tests can help determine whether a tumor is benign or malignant.
Depending on where the tumor is, tests may include:
- Biopsy: During a biopsy, a healthcare provider removes a piece of tissue, then examines the cells under a microscope.
- Imaging tests: A CT scan, MRI or ultrasound can create detailed images of structures inside your body, including tumors.
- Mammogram: A mammogram is a special type of X-ray that can detect abnormal growths or changes in breast tissue.
- X-ray: X-rays take pictures inside your body, often of bone.
Management and Treatment
How is a benign tumor treated?
Many noncancerous tumors don’t need to be treated or removed. If a neoplasm isn’t growing quickly or causing any problems, your healthcare provider may recommend keeping an eye on it.
However, if a benign tumor presses on another body structure or causes symptoms, your healthcare provider may recommend surgery to remove it. Some people also choose to have benign tumors removed for cosmetic reasons (for example, a tumor on the skin).
How can I reduce my risk of a benign tumor?
Scientists don’t fully understand what causes benign tumors. There is no way to predict or prevent them from growing.
Outlook / Prognosis
What is the outlook for people with benign tumors?
Many noncancerous tumors don’t cause any problems and don’t need to be treated. But you should keep an eye on any growth or change and have it checked regularly.
Can a benign tumor come back after treatment?
If you have surgery to remove a benign neoplasm, it usually will not grow back. Your healthcare provider will tell you if and when you should follow up to make sure.
When should I seek medical care for a benign tumor?
You should seek medical attention for any unusual growth or symptoms that could indicate a tumor.
If you’ve been diagnosed with a benign neoplasm and it doesn’t need to be treated right away, you should be aware of any changes. Call your healthcare provider if you notice any differences in the way it looks or feels or if you have increasing pain or other symptoms.
For example, if you have a benign skin tumor, call your healthcare provider if it changes:
If you have a benign brain tumor, report any:
- Problems with memory or balance.
- Vision problems.
A note from Cleveland Clinic
A benign tumor is an abnormal but noncancerous collection of cells also called a benign neoplasm. Benign tumors can form anywhere on or in your body, but many don’t need treatment. Talk to a healthcare provider if you have any unusual growth, signs of a possible tumor or changes in symptoms.
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