A tumor is a mass of tissue that’s formed by an accumulation of abnormal cells. Normally, the cells in your body age, die and are replaced by new cells. With cancer and other tumors, something disrupts this cycle. Tumor cells grow, even though the body does not need them, and unlike normal old cells, they don’t die. As this process goes on, the tumor continues to grow as more and more cells are added to the mass.
The National Cancer Institute defines a tumor as “an abnormal mass of tissue that results when cells divide more than they should or do not die when they should.”
In a healthy body, cells grow, divide, and replace each other in the body. As new cells form, the old ones die. When a person has cancer, new cells form when the body does not need them. If there are too many new cells, a group of cells, or tumors, can develop.
Types of Tumor
Benign: These are not cancerous. They either cannot spread or grow, or they do so very slowly. If a doctor removes them, they do not generally return.
Symptoms of Benign Tumors
Depending on the location, possible symptoms of a benign tumor include:
- discomfort or pain
- loss of appetite
- night sweats
- weight loss
Premalignant: In these tumors, the cells are not yet cancerous, but they have the potential to become malignant.
Malignant: Malignant tumors are cancerous. The cells can grow and spread to other parts of the body.
It is not always clear how a tumor will act in the future. Some benign tumors can become premalignant and then malignant. For this reason, it is best to monitor any growth.