A tumor is a solid mass of tissue that forms when abnormal cells group together. Tumors can affect bones, skin, tissue, organs and glands. Many tumors are not cancer (they’re benign). But they still may need treatment. Cancerous, or malignant, tumors can be life-threatening and require cancer treatment.
Tumors can form throughout the body. They can affect bone, skin, tissues, glands and organs. Neoplasm is another word for tumor.
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A tumor is a solid mass of tissue. It may or may not be cancerous.
A cyst is a small sac that may contain fluid, air or solid material. The majority of cysts are not cancerous.
A tumor may be:
Types of cancerous tumors include:
Common noncancerous tumors include:
Precancerous tumors include:
Your body is constantly making new cells to replace old or damaged ones that die off. Sometimes, the cells don’t die off as expected. Or, new cells grow and multiply faster than they should. The cells start to pile up, forming a tumor.
Tumors affect people of all ages, including children. Factors that increase the chances of developing a tumor include:
Symptoms of a tumor vary depending on where the tumor develops and whether it’s cancerous. You may be able to feel the mass, as with a breast lump.
You may experience:
Your healthcare provider performs a biopsy to determine whether a tumor is cancer. A biopsy involves removing cell samples from a tumor. A pathologist (a medical doctor who studies diseases) examines the samples in a lab to make a diagnosis. If a tumor is in an area that’s difficult to reach, your provider may remove the entire tumor and then do a biopsy.
You may also get one or more of these tests:
Treatments for a tumor depend on many factors, including the tumor type (malignant or benign) and location.
Many noncancerous tumors don’t need treatment. But some benign tumors can continue to grow. For example, benign brain tumors can press against healthy tissue, affecting vision or speech. Your healthcare provider may recommend surgery to remove the tumor.
Treatments for cancerous tumors include:
Most tumors occur for no known reason. Still, these steps may lower your risk of developing a tumor:
Benign tumors may grow and put pressure on organs like the brain. Endocrine tumors may not be cancerous but may cause your body to overproduce hormones. You may need surgery to remove the tumor.
Cancer cells can break away from the original tumor. The cells may travel in the bloodstream (circulatory system) or lymphatic system. When cells settle in a new location like an organ or gland, they start multiplying again, creating a new tumor (metastatic cancer). Cancer that spreads can be more challenging to treat.
You should call your healthcare provider if you experience:
You may want to ask your healthcare provider:
A note from Cleveland Clinic
It can be upsetting to learn that you have a tumor. You should know, though, that many tumors are benign and don’t need treatment. If a tumor is cancerous, there are a lot of treatment options. Receiving prompt treatment can make a big difference. Cancer therapies can destroy cancer cells, prevent them from spreading and lower the risk of cancer coming back. Often, people live many years after receiving treatment for cancerous tumors. Your healthcare provider can discuss your treatment options with you.
Last reviewed by a Cleveland Clinic medical professional on 10/05/2021.
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