A tumor is a growth that occurs in or on any part of the body. It comes from French, and means “an abnormal swelling of tissue.” However, a tumor is more than just being swollen. It is made up of an abnormal collection of cells, but while a tumor is not normal, it is also not synonymous with cancer. Tumors can be non-threatening to your health (benign). A tumor can be a precancerous condition—which would require removing it, or it can be cancerous (malignant). Only by taking a piece of it (biopsy) or by removing it completely (excision) and then sending it to the lab for analysis by specially trained physicians (pathologists) can one be sure what category any tumor is in.
Benign tumors do not spread and usually can be left alone. However, they can also be quite large and, due to their size, can create symptoms worrisome for a more aggressive tumor. In such cases, they would still need to be removed. Once removed, benign tumors also will not warrant further treatment beyond surgery.
Malignant tumors are cancer. They can grow, spread, and can kill. These tumors are more urgently taken to surgery and may need to be treated after surgery.